chore: lint code with golangci-lint (#1828)

* feat: add golangci-lint linting

* chore: fix linter issues

* feat: add linting into the workflow

* docs: update lint docs

* fix: cr suggestions

* fix: remove old formatting and vetting scripts

* fix: add docker make target

* fix: action go caching

* fix: depreciated actions checkout version

* fix: cr suggestion

* fix: cr suggestions

---------

Co-authored-by: Manu Gupta <manugupt1@gmail.com>

.github/workflows/ci.yml

@@ -3,6 +3,18 @@ on:
   - push
   - pull_request
 jobs:
+  lint:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - name: Set up Go
+        uses: actions/setup-go@v3
+        with:
+          go-version-file: 'go.mod'
+          cache: true
+      - name: Lint code
+        run: make lint-docker
+
   build:
     env:
       ATHENS_MONGO_STORAGE_URL: mongodb://localhost:27017
@@ -53,7 +65,7 @@ jobs:
         with:
           go-version-file: 'go.mod'
           cache: true
-      - name: Run linter
+      - name: Verify changes
         run: make verify
       - name: Unit tests
         run: go test -v -race ./...

.golangci.yml

@@ -0,0 +1,80 @@
+run:
+  tests: false
+  timeout: 5m
+
+linters-settings:
+  cyclop:
+    max-complexity: 12
+    skip-tests: true
+  gofumpt:
+    extra-rules: true
+
+linters:
+  enable-all: true
+  disable:
+    - interfacer # deprecated
+    - scopelint # deprecated
+    - maligned # deprecated
+    - golint # deprecated
+    - structcheck # deprecated
+    - deadcode # deprecated
+    - varcheck # deprecated
+    - nosnakecase # deprecated
+    - ifshort # deprecated
+    - errchkjson
+    - exhaustive
+    - exhaustivestruct
+    - exhaustruct
+    - forcetypeassert
+    - funlen
+    - gochecknoglobals
+    - gochecknoinits
+    - goconst
+    - godox
+    - goerr113
+    - gomnd
+    - ireturn
+    - lll
+    - musttag
+    - nilnil
+    - nlreturn
+    - nonamedreturns
+    - tagliatelle
+    - varnamelen
+    - wrapcheck
+    - wsl
+    - cyclop # TODO: turn this back on later
+    - gocognit # TODO: turn this back on later
+    - forbidigo # TODO: turn this back on later
+
+issues:
+  exclude-use-default: false
+  exclude:
+    - 'package-comments: should have a package comment'
+    - 'ST1000: at least one file in a package should have a package comment'
+    - 'G204: Subprocess launched with a potential tainted input or cmd arguments'
+    - 'G204: Subprocess launched with variable'
+    - 'G402: TLS MinVersion too low.'
+    - 'const `op` is unused'
+  exclude-rules:
+    - path: cmd/proxy/main.go
+      text: 'G108: Profiling endpoint is automatically exposed on /debug/pprof'
+    - path: pkg/stash/stasher.go
+      linters:
+        - contextcheck
+    - path: pkg/stash/with_azureblob.go # False positive
+      linters:
+        - bodyclose
+    - path: pkg/storage/azureblob/azureblob.go # False positive
+      linters:
+        - bodyclose
+    - path: pkg/storage/compliance/*
+      linters:
+        - thelper
+        - gosec
+        - errcheck
+    - path: pkg/index/compliance/*
+      linters:
+        - thelper
+        - gosec
+        - errcheck

DEVELOPMENT.md

@@ -234,10 +234,10 @@ Then open [http://localhost:1313](http://localhost:1313/).
 
 # Linting
 
-In our CI/CD pass, we use govet, so feel free to run it locally beforehand:
+In our CI/CD pass, we use golangci-lint, so feel free to run it locally beforehand:
 
 ```
-go vet ./...
+make lint
 ```
 
 # For People Doing a Release

Makefile

@@ -1,6 +1,8 @@
 VERSION = "unset"
 DATE=$(shell date -u +%Y-%m-%d-%H:%M:%S-%Z)
 
+GOLANGCI_LINT_VERSION=v1.51.2
+
 ifndef GOLANG_VERSION
 override GOLANG_VERSION = 1.19
 endif
@@ -43,10 +45,16 @@ docs: ## build the docs docker image
 setup-dev-env:
 	$(MAKE) dev
 
+.PHONY: lint
+lint:
+	@golangci-lint run ./...
+
+.PHONY: lint-docker
+lint-docker:
+	@docker run -t --rm -v $(CURDIR):/app -w /app golangci/golangci-lint:$(GOLANGCI_LINT_VERSION) golangci-lint run ./...
+
 .PHONY: verify
 verify: ## verify athens codebase
-	./scripts/check_gofmt.sh
-	./scripts/check_govet.sh
 	./scripts/check_deps.sh
 	./scripts/check_conflicts.sh
 

cmd/proxy/actions/app.go

@@ -16,7 +16,7 @@ import (
 	"go.opencensus.io/plugin/ochttp"
 )
 
-// Service is the name of the service that we want to tag our processes with
+// Service is the name of the service that we want to tag our processes with.
 const Service = "proxy"
 
 // App is where all routes and middleware for the proxy
@@ -126,7 +126,7 @@ func App(conf *config.Config) (http.Handler, error) {
 
 	store, err := GetStorage(conf.StorageType, conf.Storage, conf.TimeoutDuration(), client)
 	if err != nil {
-		err = fmt.Errorf("error getting storage configuration (%s)", err)
+		err = fmt.Errorf("error getting storage configuration: %w", err)
 		return nil, err
 	}
 
@@ -140,7 +140,7 @@ func App(conf *config.Config) (http.Handler, error) {
 		lggr,
 		conf,
 	); err != nil {
-		err = fmt.Errorf("error adding proxy routes (%s)", err)
+		err = fmt.Errorf("error adding proxy routes: %w", err)
 		return nil, err
 	}
 

cmd/proxy/actions/app_proxy.go

@@ -2,6 +2,7 @@ package actions
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"net/http"
 	"net/url"
@@ -54,7 +55,7 @@ func addProxyRoutes(
 		}
 		supportPath := path.Join("/sumdb", sumdbURL.Host, "/supported")
 		r.HandleFunc(supportPath, func(w http.ResponseWriter, r *http.Request) {
-			w.WriteHeader(200)
+			w.WriteHeader(http.StatusOK)
 		})
 		sumHandler := sumdbProxy(sumdbURL, c.NoSumPatterns)
 		pathPrefix := "/sumdb/" + sumdbURL.Host
@@ -63,7 +64,7 @@ func addProxyRoutes(
 		)
 	}
 
-	// Download Protocol
+	// Download Protocol:
 	// the download.Protocol and the stash.Stasher interfaces are composable
 	// in a middleware fashion. Therefore you can separate concerns
 	// by the functionality: a download.Protocol that just takes care
@@ -142,13 +143,13 @@ func getSingleFlight(l *log.Logger, c *config.Config, checker storage.Checker) (
 		return stash.WithSingleflight, nil
 	case "etcd":
 		if c.SingleFlight == nil || c.SingleFlight.Etcd == nil {
-			return nil, fmt.Errorf("Etcd config must be present")
+			return nil, errors.New("etcd config must be present")
 		}
 		endpoints := strings.Split(c.SingleFlight.Etcd.Endpoints, ",")
 		return stash.WithEtcd(endpoints, checker)
 	case "redis":
 		if c.SingleFlight == nil || c.SingleFlight.Redis == nil {
-			return nil, fmt.Errorf("Redis config must be present")
+			return nil, errors.New("redis config must be present")
 		}
 		return stash.WithRedisLock(
 			&athensLoggerForRedis{logger: l},
@@ -158,7 +159,7 @@ func getSingleFlight(l *log.Logger, c *config.Config, checker storage.Checker) (
 			c.SingleFlight.Redis.LockConfig)
 	case "redis-sentinel":
 		if c.SingleFlight == nil || c.SingleFlight.RedisSentinel == nil {
-			return nil, fmt.Errorf("Redis config must be present")
+			return nil, errors.New("redis config must be present")
 		}
 		return stash.WithRedisSentinelLock(
 			&athensLoggerForRedis{logger: l},

cmd/proxy/actions/auth.go

@@ -19,7 +19,7 @@ func initializeAuthFile(path string) {
 		return
 	}
 
-	fileBts, err := os.ReadFile(path)
+	fileBts, err := os.ReadFile(filepath.Clean(path))
 	if err != nil {
 		log.Fatalf("could not read %s: %v", path, err)
 	}
@@ -31,7 +31,7 @@ func initializeAuthFile(path string) {
 
 	fileName := transformAuthFileName(filepath.Base(path))
 	rcp := filepath.Join(hdir, fileName)
-	if err := os.WriteFile(rcp, fileBts, 0600); err != nil {
+	if err := os.WriteFile(rcp, fileBts, 0o600); err != nil {
 		log.Fatalf("could not write to file: %v", err)
 	}
 }
@@ -45,7 +45,7 @@ func netrcFromToken(tok string) {
 		log.Fatalf("netrcFromToken: could not get homedir: %v", err)
 	}
 	rcp := filepath.Join(hdir, getNETRCFilename())
-	if err := os.WriteFile(rcp, []byte(fileContent), 0600); err != nil {
+	if err := os.WriteFile(rcp, []byte(fileContent), 0o600); err != nil {
 		log.Fatalf("netrcFromToken: could not write to file: %v", err)
 	}
 }

cmd/proxy/actions/basicauth.go

@@ -8,10 +8,8 @@ import (
 	"github.com/gorilla/mux"
 )
 
-var (
+// basicAuthExcludedPaths is a regular expression that matches paths that should not be protected by HTTP basic authentication.
-	// basicAuthExcludedPaths is a regular expression that matches paths that should not be protected by HTTP basic authentication.
+var basicAuthExcludedPaths = regexp.MustCompile("^/(health|ready)z$")
-	basicAuthExcludedPaths = regexp.MustCompile("^/(health|ready)z$")
-)
 
 func basicAuth(user, pass string) mux.MiddlewareFunc {
 	return func(h http.Handler) http.Handler {
@@ -40,9 +38,5 @@ func checkAuth(r *http.Request, user, pass string) bool {
 	}
 
 	isPass := subtle.ConstantTimeCompare([]byte(pass), []byte(givenPass))
-	if isPass != 1 {
+	return isPass == 1
-		return false
-	}
-
-	return true
 }

cmd/proxy/actions/catalog.go

@@ -18,7 +18,7 @@ type catalogRes struct {
 	NextPageToken   string                `json:"next,omitempty"`
 }
 
-// catalogHandler implements GET baseURL/catalog
+// catalogHandler implements GET baseURL/catalog.
 func catalogHandler(s storage.Backend) http.HandlerFunc {
 	const op errors.Op = "actions.CatalogHandler"
 	cs, isCataloger := s.(storage.Cataloger)
@@ -54,7 +54,7 @@ func catalogHandler(s storage.Backend) http.HandlerFunc {
 }
 
 // getLimitFromParam converts a URL query parameter into an int
-// otherwise converts defaultPageSize constant
+// otherwise converts defaultPageSize constant.
 func getLimitFromParam(param string) (int, error) {
 	if param == "" {
 		return defaultPageSize, nil

cmd/proxy/actions/home.go

@@ -5,5 +5,5 @@ import (
 )
 
 func proxyHomeHandler(w http.ResponseWriter, r *http.Request) {
-	w.Write([]byte(`"Welcome to The Athens Proxy"`))
+	_, _ = w.Write([]byte(`"Welcome to The Athens Proxy"`))
 }

cmd/proxy/actions/index.go

@@ -13,7 +13,7 @@ import (
 	"github.com/sirupsen/logrus"
 )
 
-// indexHandler implements GET baseURL/index
+// indexHandler implements GET baseURL/index.
 func indexHandler(index index.Indexer) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
 		ctx := r.Context()

cmd/proxy/actions/robots.go

@@ -6,7 +6,7 @@ import (
 	"github.com/gomods/athens/pkg/config"
 )
 
-// robotsHandler implements GET baseURL/robots.txt
+// robotsHandler implements GET baseURL/robots.txt.
 func robotsHandler(c *config.Config) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
 		http.ServeFile(w, r, c.RobotsFile)

cmd/proxy/actions/storage.go

@@ -21,7 +21,7 @@ import (
 	"github.com/spf13/afero"
 )
 
-// GetStorage returns storage backend based on env configuration
+// GetStorage returns storage backend based on env configuration.
 func GetStorage(storageType string, storageConfig *config.Storage, timeout time.Duration, client *http.Client) (storage.Backend, error) {
 	const op errors.Op = "actions.GetStorage"
 	switch storageType {

cmd/proxy/actions/sumdb.go

@@ -17,12 +17,12 @@ func sumdbProxy(url *url.URL, nosumPatterns []string) http.Handler {
 		req.URL.Host = url.Host
 	}
 	if len(nosumPatterns) > 0 {
-		return noSumWrapper(rp, url.Host, nosumPatterns)
+		return noSumWrapper(rp, nosumPatterns)
 	}
 	return rp
 }
 
-func noSumWrapper(h http.Handler, host string, patterns []string) http.Handler {
+func noSumWrapper(h http.Handler, patterns []string) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		if strings.HasPrefix(r.URL.Path, "/lookup/") {
 			for _, p := range patterns {

cmd/proxy/actions/sumdb_test.go

@@ -97,7 +97,7 @@ func TestNoSumPatterns(t *testing.T) {
 	for _, tc := range noSumTestCases {
 		t.Run(tc.name, func(t *testing.T) {
 			w := httptest.NewRecorder()
-			skipHandler := noSumWrapper(http.HandlerFunc(emptyHandler), "sum.golang.org", tc.patterns)
+			skipHandler := noSumWrapper(http.HandlerFunc(emptyHandler), tc.patterns)
 			req := httptest.NewRequest("GET", "/lookup/"+tc.given, nil)
 			skipHandler.ServeHTTP(w, req)
 			if tc.status != w.Code {

cmd/proxy/actions/version.go

@@ -8,5 +8,5 @@ import (
 )
 
 func versionHandler(w http.ResponseWriter, r *http.Request) {
-	json.NewEncoder(w).Encode(build.Data())
+	_ = json.NewEncoder(w).Encode(build.Data())
 }

cmd/proxy/main.go

@@ -2,16 +2,16 @@ package main
 
 import (
 	"context"
+	"errors"
 	"flag"
 	"fmt"
 	"log"
 	"net/http"
+	_ "net/http/pprof"
 	"os"
 	"os/signal"
 	"time"
 
-	_ "net/http/pprof"
-
 	"github.com/gomods/athens/cmd/proxy/actions"
 	"github.com/gomods/athens/internal/shutdown"
 	"github.com/gomods/athens/pkg/build"
@@ -45,8 +45,9 @@ func main() {
 	}
 
 	srv := &http.Server{
-		Addr:    conf.Port,
+		Addr:              conf.Port,
-		Handler: handler,
+		Handler:           handler,
+		ReadHeaderTimeout: 2 * time.Second,
 	}
 	idleConnsClosed := make(chan struct{})
 
@@ -54,7 +55,7 @@ func main() {
 		sigint := make(chan os.Signal, 1)
 		signal.Notify(sigint, shutdown.GetSignals()...)
 		s := <-sigint
-		log.Printf("Recived signal (%s): Shutting down server", s)
+		log.Printf("Received signal (%s): Shutting down server", s)
 
 		// We received an interrupt signal, shut down.
 		ctx, cancel := context.WithTimeout(context.Background(), time.Second*time.Duration(conf.ShutdownTimeout))
@@ -70,7 +71,7 @@ func main() {
 			// pprof to be exposed on a different port than the application for security matters, not to expose profiling data and avoid DoS attacks (profiling slows down the service)
 			// https://www.farsightsecurity.com/txt-record/2016/10/28/cmikk-go-remote-profiling/
 			log.Printf("Starting `pprof` at port %v", conf.PprofPort)
-			log.Fatal(http.ListenAndServe(conf.PprofPort, nil))
+			log.Fatal(http.ListenAndServe(conf.PprofPort, nil)) //nolint:gosec // This should not be exposed to the world.
 		}()
 	}
 
@@ -81,7 +82,7 @@ func main() {
 		err = srv.ListenAndServe()
 	}
 
-	if err != http.ErrServerClosed {
+	if !errors.Is(err, http.ErrServerClosed) {
 		log.Fatal(err)
 	}
 

init.ps1

@@ -79,8 +79,6 @@ if ($docs.IsPresent) {
 }
 
 if ($verify.IsPresent) {
-	execScript "check_gofmt.ps1"
-	execScript "check_govet.ps1"
 	execScript "check_deps.ps1"
 }
 

pkg/build/build.go

@@ -9,7 +9,7 @@ import (
 	"fmt"
 )
 
-// Details represents known data for a given build
+// Details represents known data for a given build.
 type Details struct {
 	Version string `json:"version,omitempty"`
 	Date    string `json:"date,omitempty"`
@@ -29,7 +29,7 @@ func String() string {
 	return fmt.Sprintf("Build Details:\n\tVersion:\t%s\n\tDate:\t\t%s", version, buildDate)
 }
 
-// Data returns build details as a struct
+// Data returns build details as a struct.
 func Data() Details {
 	return Details{
 		Version: version,

pkg/config/azureblob.go

@@ -1,6 +1,6 @@
 package config
 
-// AzureBlobConfig specifies the properties required to use Azure as the storage backend
+// AzureBlobConfig specifies the properties required to use Azure as the storage backend.
 type AzureBlobConfig struct {
 	AccountName   string `validate:"required" envconfig:"ATHENS_AZURE_ACCOUNT_NAME"`
 	AccountKey    string `validate:"required" envconfig:"ATHENS_AZURE_ACCOUNT_KEY"`

pkg/config/config.go

@@ -18,7 +18,7 @@ import (
 
 const defaultConfigFile = "athens.toml"
 
-// Config provides configuration values for all components
+// Config provides configuration values for all components.
 type Config struct {
 	TimeoutConf
 	GoEnv            string    `validate:"required" envconfig:"GO_ENV"`
@@ -63,12 +63,12 @@ type Config struct {
 }
 
 // EnvList is a list of key-value environment
-// variables that are passed to the Go command
+// variables that are passed to the Go command.
 type EnvList []string
 
 // HasKey returns whether a key-value entry
 // is present by only checking the left of
-// key=value
+// key=value.
 func (el EnvList) HasKey(key string) bool {
 	for _, env := range el {
 		if strings.HasPrefix(env, key+"=") {
@@ -79,7 +79,7 @@ func (el EnvList) HasKey(key string) bool {
 }
 
 // Add adds a key=value entry to the environment
-// list
+// list.
 func (el *EnvList) Add(key, value string) {
 	*el = append(*el, key+"="+value)
 }
@@ -110,7 +110,7 @@ func (el *EnvList) Decode(value string) error {
 }
 
 // Validate validates that all strings inside the
-// list are of the key=value format
+// list are of the key=value format.
 func (el EnvList) Validate() error {
 	const op errors.Op = "EnvList.Validate"
 	for _, env := range el {
@@ -123,7 +123,7 @@ func (el EnvList) Validate() error {
 }
 
 // Load loads the config from a file.
-// If file is not present returns default config
+// If file is not present returns default config.
 func Load(configFile string) (*Config, error) {
 	// User explicitly specified a config file
 	if configFile != "" {
@@ -206,7 +206,7 @@ func defaultConfig() *Config {
 }
 
 // BasicAuth returns BasicAuthUser and BasicAuthPassword
-// and ok if neither of them are empty
+// and ok if neither of them are empty.
 func (c *Config) BasicAuth() (user, pass string, ok bool) {
 	user = c.BasicAuthUser
 	pass = c.BasicAuthPass
@@ -215,7 +215,7 @@ func (c *Config) BasicAuth() (user, pass string, ok bool) {
 }
 
 // TLSCertFiles returns certificate and key files and an error if
-// both files doesn't exist and have approperiate file permissions
+// both files doesn't exist and have approperiate file permissions.
 func (c *Config) TLSCertFiles() (cert, key string, err error) {
 	if c.TLSCertFile == "" && c.TLSKeyFile == "" {
 		return "", "", nil
@@ -223,29 +223,28 @@ func (c *Config) TLSCertFiles() (cert, key string, err error) {
 
 	certFile, err := os.Stat(c.TLSCertFile)
 	if err != nil {
-		return "", "", fmt.Errorf("Could not access TLSCertFile: %v", err)
+		return "", "", fmt.Errorf("could not access TLSCertFile: %w", err)
 	}
 
 	keyFile, err := os.Stat(c.TLSKeyFile)
 	if err != nil {
-		return "", "", fmt.Errorf("Could not access TLSKeyFile: %v", err)
+		return "", "", fmt.Errorf("could not access TLSKeyFile: %w", err)
 	}
 
-	if keyFile.Mode()&077 != 0 && runtime.GOOS != "windows" {
+	if keyFile.Mode()&0o077 != 0 && runtime.GOOS != "windows" {
 		return "", "", fmt.Errorf("TLSKeyFile should not be accessible by others")
 	}
 
 	return certFile.Name(), keyFile.Name(), nil
 }
 
-// FilterOff returns true if the FilterFile is empty
+// FilterOff returns true if the FilterFile is empty.
 func (c *Config) FilterOff() bool {
 	return c.FilterFile == ""
 }
 
-// ParseConfigFile parses the given file into an athens config struct
+// ParseConfigFile parses the given file into an athens config struct.
 func ParseConfigFile(configFile string) (*Config, error) {
-
 	var config Config
 	// attempt to read the given config file
 	if _, err := toml.DecodeFile(configFile, &config); err != nil {
@@ -271,7 +270,7 @@ func ParseConfigFile(configFile string) (*Config, error) {
 	return &config, nil
 }
 
-// envOverride uses Environment variables to override unspecified properties
+// envOverride uses Environment variables to override unspecified properties.
 func envOverride(config *Config) error {
 	const defaultPort = ":3000"
 	err := envconfig.Process("athens", config)
@@ -355,16 +354,16 @@ func validateIndex(validate *validator.Validate, indexType string, config *Index
 func GetConf(path string) (*Config, error) {
 	absPath, err := filepath.Abs(path)
 	if err != nil {
-		return nil, fmt.Errorf("Unable to construct absolute path to test config file")
+		return nil, fmt.Errorf("unable to construct absolute path to test config file")
 	}
 	conf, err := ParseConfigFile(absPath)
 	if err != nil {
-		return nil, fmt.Errorf("Unable to parse test config file: %s", err.Error())
+		return nil, fmt.Errorf("unable to parse test config file: %w", err)
 	}
 	return conf, nil
 }
 
-// checkFilePerms given a list of files
+// checkFilePerms given a list of files.
 func checkFilePerms(files ...string) error {
 	const op = "config.checkFilePerms"
 
@@ -384,10 +383,9 @@ func checkFilePerms(files ...string) error {
 		// Assume unix based system (MacOS and Linux)
 		// the bit mask is calculated using the umask command which tells which permissions
 		// should not be allowed for a particular user, group or world
-		if fInfo.Mode()&0077 != 0 && runtime.GOOS != "windows" {
+		if fInfo.Mode()&0o077 != 0 && runtime.GOOS != "windows" {
 			return errors.E(op, f+" should have at most rwx,-, - (bit mask 077) as permission")
 		}
-
 	}
 
 	return nil

pkg/config/disk.go

@@ -1,6 +1,6 @@
 package config
 
-// DiskConfig specifies the properties required to use Disk as the storage backend
+// DiskConfig specifies the properties required to use Disk as the storage backend.
 type DiskConfig struct {
 	RootPath string `validate:"required" envconfig:"ATHENS_DISK_STORAGE_ROOT"`
 }

pkg/config/external.go

@@ -1,6 +1,6 @@
 package config
 
-// External specifies configuration for an external http storage
+// External specifies configuration for an external http storage.
 type External struct {
 	URL string `validate:"required" envconfig:"ATHENS_EXTERNAL_STORAGE_URL"`
 }

pkg/config/gcp.go

@@ -1,6 +1,6 @@
 package config
 
-// GCPConfig specifies the properties required to use GCP as the storage backend
+// GCPConfig specifies the properties required to use GCP as the storage backend.
 type GCPConfig struct {
 	ProjectID string `envconfig:"GOOGLE_CLOUD_PROJECT"`
 	Bucket    string `validate:"required" envconfig:"ATHENS_STORAGE_GCP_BUCKET"`

pkg/config/index.go

@@ -1,6 +1,6 @@
 package config
 
-// Index is the config for various index storage backends
+// Index is the config for various index storage backends.
 type Index struct {
 	MySQL    *MySQL
 	Postgres *Postgres

pkg/config/minio.go

@@ -1,7 +1,7 @@
 package config
 
 // MinioConfig specifies the properties required to use Minio or DigitalOcean Spaces
-// as the storage backend
+// as the storage backend.
 type MinioConfig struct {
 	Endpoint  string `validate:"required" envconfig:"ATHENS_MINIO_ENDPOINT"`
 	Key       string `validate:"required" envconfig:"ATHENS_MINIO_ACCESS_KEY_ID"`

pkg/config/module.go

@@ -7,20 +7,20 @@ import (
 )
 
 // PackageVersionedName return package full name used in storage.
-// E.g athens/@v/v1.0.mod
+// E.g athens/@v/v1.0.mod.
 func PackageVersionedName(module, version, ext string) string {
 	return fmt.Sprintf("%s/@v/%s.%s", module, version, ext)
 }
 
 // FmtModVer is a helper function that can take
-// pkg/a/b and v2.3.1 and returns pkg/a/b@v2.3.1
+// pkg/a/b and v2.3.1 and returns pkg/a/b@v2.3.1.
 func FmtModVer(mod, ver string) string {
 	return fmt.Sprintf("%s@%s", mod, ver)
 }
 
 // ModuleVersionFromPath returns module and version from a
-// storage path
+// storage path.
-// E.g athens/@v/v1.0.info -> athens and v.1.0
+// E.g athens/@v/v1.0.info -> athens and v.1.0.
 func ModuleVersionFromPath(path string) (string, string) {
 	segments := strings.Split(path, "/@v/")
 	if len(segments) != 2 {

pkg/config/mongo.go

@@ -1,6 +1,6 @@
 package config
 
-// MongoConfig specifies the properties required to use MongoDB as the storage backend
+// MongoConfig specifies the properties required to use MongoDB as the storage backend.
 type MongoConfig struct {
 	URL                   string `validate:"required" envconfig:"ATHENS_MONGO_STORAGE_URL"`
 	DefaultDBName         string `envconfig:"ATHENS_MONGO_DEFAULT_DATABASE" default:"athens"`

pkg/config/mysql.go

@@ -1,6 +1,6 @@
 package config
 
-// MySQL config
+// MySQL config.
 type MySQL struct {
 	Protocol string            `validate:"required" envconfig:"ATHENS_INDEX_MYSQL_PROTOCOL"`
 	Host     string            `validate:"required" envconfig:"ATHENS_INDEX_MYSQL_HOST"`

pkg/config/postgres.go

@@ -1,6 +1,6 @@
 package config
 
-// Postgres config
+// Postgres config.
 type Postgres struct {
 	Host     string            `validate:"required" envconfig:"ATHENS_INDEX_POSTGRES_HOST"`
 	Port     int               `validate:"required" envconfig:"ATHENS_INDEX_POSTGRES_PORT"`

pkg/config/s3.go

@@ -1,6 +1,6 @@
 package config
 
-// S3Config specifies the properties required to use S3 as the storage backend
+// S3Config specifies the properties required to use S3 as the storage backend.
 type S3Config struct {
 	Region                             string `validate:"required" envconfig:"AWS_REGION"`
 	Key                                string `envconfig:"AWS_ACCESS_KEY_ID"`

pkg/config/singleflight.go

@@ -25,7 +25,7 @@ type Redis struct {
 }
 
 // RedisSentinel is the configuration for using redis with sentinel
-// for SingleFlight
+// for SingleFlight.
 type RedisSentinel struct {
 	Endpoints        []string `envconfig:"ATHENS_REDIS_SENTINEL_ENDPOINTS"`
 	MasterName       string   `envconfig:"ATHENS_REDIS_SENTINEL_MASTER_NAME"`
@@ -33,12 +33,14 @@ type RedisSentinel struct {
 	LockConfig       *RedisLockConfig
 }
 
+// RedisLockConfig is the configuration for redis locking.
 type RedisLockConfig struct {
 	Timeout    int `envconfig:"ATHENS_REDIS_LOCK_TIMEOUT"`
 	TTL        int `envconfig:"ATHENS_REDIS_LOCK_TTL"`
 	MaxRetries int `envconfig:"ATHENS_REDIS_LOCK_MAX_RETRIES"`
 }
 
+// DefaultRedisLockConfig returns the default redis locking configuration.
 func DefaultRedisLockConfig() *RedisLockConfig {
 	return &RedisLockConfig{
 		TTL:        900,

pkg/config/storage.go

@@ -1,6 +1,6 @@
 package config
 
-// Storage provides configs for various storage backends
+// Storage provides configs for various storage backends.
 type Storage struct {
 	Disk      *DiskConfig
 	GCP       *GCPConfig

pkg/config/timeout.go

@@ -2,17 +2,17 @@ package config
 
 import "time"
 
-// TimeoutConf is a common struct for anything with a timeout
+// TimeoutConf is a common struct for anything with a timeout.
 type TimeoutConf struct {
 	Timeout int `validate:"required"`
 }
 
-// TimeoutDuration returns the timeout as time.duration
+// TimeoutDuration returns the timeout as time.duration.
 func (t *TimeoutConf) TimeoutDuration() time.Duration {
 	return GetTimeoutDuration(t.Timeout)
 }
 
-// GetTimeoutDuration returns the timeout as time.duration
+// GetTimeoutDuration returns the timeout as time.duration.
 func GetTimeoutDuration(timeout int) time.Duration {
 	return time.Second * time.Duration(timeout)
 }

pkg/download/get_module_params.go

@@ -7,7 +7,7 @@ import (
 	"github.com/gomods/athens/pkg/paths"
 )
 
-func getModuleParams(r *http.Request, op errors.Op) (mod string, ver string, err error) {
+func getModuleParams(r *http.Request, op errors.Op) (mod, ver string, err error) {
 	params, err := paths.GetAllParams(r)
 	if err != nil {
 		return "", "", errors.E(op, err, errors.KindBadRequest)

pkg/download/handler.go

@@ -15,8 +15,7 @@ import (
 // a ready-to-go http handler that serves up cmd/go's download protocol.
 type ProtocolHandler func(dp Protocol, lggr log.Entry, df *mode.DownloadFile) http.Handler
 
-// HandlerOpts are the generic options
+// HandlerOpts are the generic options for a ProtocolHandler.
-// for a ProtocolHandler
 type HandlerOpts struct {
 	Protocol     Protocol
 	Logger       *log.Logger
@@ -26,7 +25,7 @@ type HandlerOpts struct {
 // LogEntryHandler pulls a log entry from the request context. Thanks to the
 // LogEntryMiddleware, we should have a log entry stored in the context for each
 // request with request-specific fields. This will grab the entry and pass it to
-// the protocol handlers
+// the protocol handlers.
 func LogEntryHandler(ph ProtocolHandler, opts *HandlerOpts) http.Handler {
 	f := func(w http.ResponseWriter, r *http.Request) {
 		ent := log.EntryFromContext(r.Context())

pkg/download/latest.go

@@ -13,7 +13,7 @@ import (
 // PathLatest URL.
 const PathLatest = "/{module:.+}/@latest"
 
-// LatestHandler implements GET baseURL/module/@latest
+// LatestHandler implements GET baseURL/module/@latest.
 func LatestHandler(dp Protocol, lggr log.Entry, df *mode.DownloadFile) http.Handler {
 	const op errors.Op = "download.LatestHandler"
 	f := func(w http.ResponseWriter, r *http.Request) {

pkg/download/list.go

@@ -14,7 +14,7 @@ import (
 // PathList URL.
 const PathList = "/{module:.+}/@v/list"
 
-// ListHandler implements GET baseURL/module/@v/list
+// ListHandler implements GET baseURL/module/@v/list.
 func ListHandler(dp Protocol, lggr log.Entry, df *mode.DownloadFile) http.Handler {
 	const op errors.Op = "download.ListHandler"
 	f := func(w http.ResponseWriter, r *http.Request) {

pkg/download/mode/mode.go

@@ -4,6 +4,7 @@ import (
 	"encoding/base64"
 	"fmt"
 	"os"
+	"path/filepath"
 	"strings"
 
 	"github.com/gomods/athens/pkg/errors"
@@ -16,7 +17,7 @@ import (
 // when a module is not found in storage.
 type Mode string
 
-// DownloadMode constants. For more information see config.dev.toml
+// DownloadMode constants. For more information see config.dev.toml.
 const (
 	Sync            Mode = "sync"
 	Async           Mode = "async"
@@ -59,7 +60,7 @@ func NewFile(m Mode, downloadURL string) (*DownloadFile, error) {
 
 	if strings.HasPrefix(string(m), "file:") {
 		filePath := string(m[5:])
-		bts, err := os.ReadFile(filePath)
+		bts, err := os.ReadFile(filepath.Clean(filePath))
 		if err != nil {
 			return nil, err
 		}

pkg/download/protocol.go

@@ -48,7 +48,7 @@ type Opts struct {
 	NetworkMode  string
 }
 
-// NetworkMode constants
+// NetworkMode constants.
 const (
 	Strict   = "strict"
 	Offline  = "offline"
@@ -263,12 +263,12 @@ func (p *protocol) processDownload(ctx context.Context, mod, ver string, f func(
 		}
 		return f(newVer)
 	case mode.Async:
-		go p.stasher.Stash(ctx, mod, ver)
+		go func() { _, _ = p.stasher.Stash(ctx, mod, ver) }()
 		return errors.E(op, "async: module not found", errors.KindNotFound)
 	case mode.Redirect:
 		return errors.E(op, "redirect", errors.KindRedirect)
 	case mode.AsyncRedirect:
-		go p.stasher.Stash(ctx, mod, ver)
+		go func() { _, _ = p.stasher.Stash(ctx, mod, ver) }()
 		return errors.E(op, "async_redirect: module not found", errors.KindRedirect)
 	case mode.None:
 		return errors.E(op, "none", errors.KindNotFound)
@@ -276,7 +276,7 @@ func (p *protocol) processDownload(ctx context.Context, mod, ver string, f func(
 	return nil
 }
 
-// union concatenates two version lists and removes duplicates
+// union concatenates two version lists and removes duplicates.
 func union(list1, list2 []string) []string {
 	if list1 == nil {
 		list1 = []string{}
@@ -284,10 +284,10 @@ func union(list1, list2 []string) []string {
 	if list2 == nil {
 		list2 = []string{}
 	}
-	list := append(list1, list2...)
+	list1 = append(list1, list2...)
 	unique := []string{}
 	m := make(map[string]struct{})
-	for _, v := range list {
+	for _, v := range list1 {
 		if _, ok := m[v]; !ok {
 			unique = append(unique, v)
 			m[v] = struct{}{}

pkg/download/version_info.go

@@ -11,7 +11,7 @@ import (
 // PathVersionInfo URL.
 const PathVersionInfo = "/{module:.+}/@v/{version}.info"
 
-// InfoHandler implements GET baseURL/module/@v/version.info
+// InfoHandler implements GET baseURL/module/@v/version.info.
 func InfoHandler(dp Protocol, lggr log.Entry, df *mode.DownloadFile) http.Handler {
 	const op errors.Op = "download.InfoHandler"
 	f := func(w http.ResponseWriter, r *http.Request) {
@@ -38,7 +38,7 @@ func InfoHandler(dp Protocol, lggr log.Entry, df *mode.DownloadFile) http.Handle
 			w.WriteHeader(errors.Kind(err))
 		}
 
-		w.Write(info)
+		_, _ = w.Write(info)
 	}
 	return http.HandlerFunc(f)
 }

pkg/download/version_module.go

@@ -11,7 +11,7 @@ import (
 // PathVersionModule URL.
 const PathVersionModule = "/{module:.+}/@v/{version}.mod"
 
-// ModuleHandler implements GET baseURL/module/@v/version.mod
+// ModuleHandler implements GET baseURL/module/@v/version.mod.
 func ModuleHandler(dp Protocol, lggr log.Entry, df *mode.DownloadFile) http.Handler {
 	const op errors.Op = "download.VersionModuleHandler"
 	f := func(w http.ResponseWriter, r *http.Request) {
@@ -42,7 +42,7 @@ func ModuleHandler(dp Protocol, lggr log.Entry, df *mode.DownloadFile) http.Hand
 			return
 		}
 
-		w.Write(modBts)
+		_, _ = w.Write(modBts)
 	}
 	return http.HandlerFunc(f)
 }

pkg/download/version_zip.go

@@ -13,7 +13,7 @@ import (
 // PathVersionZip URL.
 const PathVersionZip = "/{module:.+}/@v/{version}.zip"
 
-// ZipHandler implements GET baseURL/module/@v/version.zip
+// ZipHandler implements GET baseURL/module/@v/version.zip.
 func ZipHandler(dp Protocol, lggr log.Entry, df *mode.DownloadFile) http.Handler {
 	const op errors.Op = "download.ZipHandler"
 	f := func(w http.ResponseWriter, r *http.Request) {
@@ -41,7 +41,7 @@ func ZipHandler(dp Protocol, lggr log.Entry, df *mode.DownloadFile) http.Handler
 			w.WriteHeader(errors.Kind(err))
 			return
 		}
-		defer zip.Close()
+		defer func() { _ = zip.Close() }()
 
 		w.Header().Set("Content-Type", "application/zip")
 		size := zip.Size()

pkg/errors/errors.go

@@ -9,7 +9,7 @@ import (
 	"github.com/sirupsen/logrus"
 )
 
-// Kind enums
+// Kind enums.
 const (
 	KindNotFound       = http.StatusNotFound
 	KindBadRequest     = http.StatusBadRequest
@@ -55,6 +55,16 @@ func Is(err error, kind int) bool {
 	return Kind(err) == kind
 }
 
+// IsErr is a convenience wrapper around the std library errors.Is.
+func IsErr(err, target error) bool {
+	return errors.Is(err, target)
+}
+
+// AsErr is a convenience wrapper around the std library errors.As.
+func AsErr(err error, target any) bool {
+	return errors.As(err, target)
+}
+
 // Op describes any independent function or
 // method in Athens. A series of operations
 // forms a more readable stack trace.
@@ -69,7 +79,7 @@ func (o Op) String() string {
 // a module from a regular error string or version.
 type M string
 
-// V represents a module version in an error
+// V represents a module version in an error.
 type V string
 
 // E is a helper function to construct an Error type
@@ -114,8 +124,8 @@ func E(op Op, args ...interface{}) error {
 // if none exists, then the level is Error because
 // it is an unexpected.
 func Severity(err error) logrus.Level {
-	e, ok := err.(Error)
+	var e Error
-	if !ok {
+	if !errors.As(err, &e) {
 		return logrus.ErrorLevel
 	}
 
@@ -145,8 +155,8 @@ func Expect(err error, kinds ...int) logrus.Level {
 // Kind recursively searches for the
 // first error kind it finds.
 func Kind(err error) int {
-	e, ok := err.(Error)
+	var e Error
-	if !ok {
+	if !errors.As(err, &e) {
 		return KindUnexpected
 	}
 
@@ -173,6 +183,7 @@ func KindText(err error) string {
 func Ops(err Error) []Op {
 	ops := []Op{err.Op}
 	for {
+		//nolint:errorlint // We iterate the errors anyway.
 		embeddedErr, ok := err.Err.(Error)
 		if !ok {
 			break

pkg/errors/kinds.go

@@ -1,6 +1,6 @@
 package errors
 
-// IsNotFoundErr helper function for KindNotFound
+// IsNotFoundErr helper function for KindNotFound.
 func IsNotFoundErr(err error) bool {
 	return Kind(err) == KindNotFound
 }

pkg/index/compliance/compliance.go

@@ -21,7 +21,7 @@ func RunTests(t *testing.T, indexer index.Indexer, clearIndex func() error) {
 		t.Fatal(err)
 	}
 
-	var tests = []struct {
+	tests := []struct {
 		name    string
 		desc    string
 		limit   int

pkg/index/indexer.go

@@ -13,7 +13,7 @@ type Line struct {
 }
 
 // Indexer is an interface that can process new module@versions
-// and also retrieve 'limit' module@versions that were indexed after 'since'
+// and also retrieve 'limit' module@versions that were indexed after 'since'.
 type Indexer interface {
 	// Index stores the module@version into the index backend.
 	// Implementer must create the Timestamp at the time and set it

pkg/index/mem/mem.go

@@ -10,7 +10,7 @@ import (
 	"github.com/gomods/athens/pkg/index"
 )
 
-// New returns a new in-memory indexer
+// New returns a new in-memory indexer.
 func New() index.Indexer {
 	return &indexer{}
 }

pkg/index/mysql/mysql.go

@@ -83,8 +83,8 @@ func (i *indexer) Lines(ctx context.Context, since time.Time, limit int) ([]*ind
 	if err != nil {
 		return nil, errors.E(op, err)
 	}
-	defer rows.Close()
+	defer func() { _ = rows.Close() }()
-	lines := []*index.Line{}
+	var lines []*index.Line
 	for rows.Next() {
 		var line index.Line
 		err = rows.Scan(&line.Path, &line.Version, &line.Timestamp)
@@ -108,13 +108,14 @@ func getMySQLSource(cfg *config.MySQL) string {
 }
 
 func getKind(err error) int {
-	mysqlErr, ok := err.(*mysql.MySQLError)
+	mysqlErr := &mysql.MySQLError{}
-	if !ok {
+	if !errors.AsErr(err, &mysqlErr) {
 		return errors.KindUnexpected
 	}
 	switch mysqlErr.Number {
 	case 1062:
 		return errors.KindAlreadyExists
+	default:
+		return errors.KindUnexpected
 	}
-	return errors.KindUnexpected
 }

pkg/index/nop/nop.go

@@ -7,7 +7,7 @@ import (
 	"github.com/gomods/athens/pkg/index"
 )
 
-// New returns a no-op Indexer
+// New returns a no-op Indexer.
 func New() index.Indexer {
 	return indexer{}
 }
@@ -17,6 +17,7 @@ type indexer struct{}
 func (indexer) Index(ctx context.Context, mod, ver string) error {
 	return nil
 }
+
 func (indexer) Lines(ctx context.Context, since time.Time, limit int) ([]*index.Line, error) {
 	return []*index.Line{}, nil
 }

pkg/index/postgres/postgres.go

@@ -7,17 +7,15 @@ import (
 	"strings"
 	"time"
 
-	// register the driver with database/sql
-	"github.com/lib/pq"
-
 	"github.com/gomods/athens/pkg/config"
 	"github.com/gomods/athens/pkg/errors"
 	"github.com/gomods/athens/pkg/index"
+	"github.com/lib/pq"
 )
 
 // New returns a new Indexer with a PostgreSQL implementation.
 // It attempts to connect to the DB and create the index table
-// if it doesn ot already exist.
+// if it does not already exist.
 func New(cfg *config.Postgres) (index.Indexer, error) {
 	dataSource := getPostgresSource(cfg)
 	db, err := sql.Open("postgres", dataSource)
@@ -42,7 +40,7 @@ var schema = [...]string{
 			id SERIAL PRIMARY KEY,
 			path VARCHAR(255) NOT NULL,
 			version VARCHAR(255) NOT NULL,
-			timestamp timestamp NOT NULL
+			timestamp TIMESTAMP NOT NULL
 		)
 	`,
 	`
@@ -82,8 +80,8 @@ func (i *indexer) Lines(ctx context.Context, since time.Time, limit int) ([]*ind
 	if err != nil {
 		return nil, errors.E(op, err)
 	}
-	defer rows.Close()
+	defer func() { _ = rows.Close() }()
-	lines := []*index.Line{}
+	var lines []*index.Line
 	for rows.Next() {
 		var line index.Line
 		err = rows.Scan(&line.Path, &line.Version, &line.Timestamp)
@@ -96,7 +94,7 @@ func (i *indexer) Lines(ctx context.Context, since time.Time, limit int) ([]*ind
 }
 
 func getPostgresSource(cfg *config.Postgres) string {
-	args := []string{}
+	args := make([]string, 0, 5+len(cfg.Params))
 	args = append(args, "host="+cfg.Host)
 	args = append(args, "port=", strconv.Itoa(cfg.Port))
 	args = append(args, "user=", cfg.User)
@@ -109,13 +107,14 @@ func getPostgresSource(cfg *config.Postgres) string {
 }
 
 func getKind(err error) int {
-	pqerr, ok := err.(*pq.Error)
+	pqerr := &pq.Error{}
-	if !ok {
+	if !errors.AsErr(err, &pqerr) {
 		return errors.KindUnexpected
 	}
 	switch pqerr.Code {
 	case "23505":
 		return errors.KindAlreadyExists
+	default:
+		return errors.KindUnexpected
 	}
-	return errors.KindUnexpected
 }

pkg/log/entry.go

@@ -35,8 +35,8 @@ func (e *entry) WithFields(fields map[string]interface{}) Entry {
 }
 
 func (e *entry) SystemErr(err error) {
-	athensErr, ok := err.(errors.Error)
+	var athensErr errors.Error
-	if !ok {
+	if !errors.IsErr(err, athensErr) {
 		e.Error(err)
 		return
 	}

pkg/log/log.go

@@ -41,7 +41,7 @@ func (l *Logger) WithFields(fields map[string]interface{}) Entry {
 	return &entry{e}
 }
 
-// NoOpLogger provides a Logger that does nothing
+// NoOpLogger provides a Logger that does nothing.
 func NoOpLogger() *Logger {
 	return &Logger{
 		Logger: &logrus.Logger{},

pkg/log/log_context.go

@@ -8,14 +8,14 @@ type ctxKey string
 
 const logEntryKey ctxKey = "log-entry-context-key"
 
-// SetEntryInContext stores an Entry in the request context
+// SetEntryInContext stores an Entry in the request context.
 func SetEntryInContext(ctx context.Context, e Entry) context.Context {
 	return context.WithValue(ctx, logEntryKey, e)
 }
 
 // EntryFromContext returns an Entry that has been stored in the request context.
 // If there is no value for the key or the type assertion fails, it returns a new
-// entry from the provided logger
+// entry from the provided logger.
 func EntryFromContext(ctx context.Context) Entry {
 	e, ok := ctx.Value(logEntryKey).(Entry)
 	if !ok || e == nil {

pkg/middleware/content_type.go

@@ -4,7 +4,7 @@ import (
 	"net/http"
 )
 
-// ContentType writes writes an application/json
+// ContentType writes an application/json
 // Content-Type header.
 func ContentType(h http.Handler) http.Handler {
 	f := func(w http.ResponseWriter, r *http.Request) {

pkg/middleware/log_entry.go

@@ -10,7 +10,7 @@ import (
 )
 
 // LogEntryMiddleware builds a log.Entry, setting the request fields
-// and storing it in the context to be used throughout the stack
+// and storing it in the context to be used throughout the stack.
 func LogEntryMiddleware(lggr *log.Logger) mux.MiddlewareFunc {
 	return func(h http.Handler) http.Handler {
 		f := func(w http.ResponseWriter, r *http.Request) {

pkg/middleware/requestid.go

@@ -9,7 +9,7 @@ import (
 
 // WithRequestID ensures a request id is in the
 // request context by either the incoming header
-// or creating a new one
+// or creating a new one.
 func WithRequestID(h http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		requestID := r.Header.Get(requestid.HeaderKey)

pkg/middleware/validation.go

@@ -14,7 +14,7 @@ import (
 )
 
 // NewValidationMiddleware builds a middleware function that performs validation checks by calling
-// an external webhook
+// an external webhook.
 func NewValidationMiddleware(client *http.Client, validatorHook string) mux.MiddlewareFunc {
 	const op errors.Op = "actions.NewValidationMiddleware"
 	return func(h http.Handler) http.Handler {
@@ -50,7 +50,7 @@ func NewValidationMiddleware(client *http.Client, validatorHook string) mux.Midd
 	}
 }
 
-func maybeLogValidationReason(context context.Context, message string, mod string, version string) {
+func maybeLogValidationReason(context context.Context, message, mod, version string) {
 	if len(message) > 0 {
 		entry := log.EntryFromContext(context)
 		entry.Warnf("error validating %s@%s %s", mod, version, message)
@@ -85,6 +85,10 @@ func validate(ctx context.Context, client *http.Client, hook, mod, ver string) (
 	if err != nil {
 		return validationResponse{Valid: false}, errors.E(op, err)
 	}
+	defer func() {
+		_, _ = io.Copy(io.Discard, resp.Body)
+		_ = resp.Body.Close()
+	}()
 
 	switch resp.StatusCode {
 	case http.StatusOK:
@@ -97,8 +101,6 @@ func validate(ctx context.Context, client *http.Client, hook, mod, ver string) (
 }
 
 func validationResponseFromRequest(resp *http.Response) validationResponse {
-	defer resp.Body.Close()
-
 	body, _ := io.ReadAll(resp.Body)
 	return validationResponse{Valid: resp.StatusCode == http.StatusOK, Message: body}
 }

pkg/module/fetcher.go

@@ -6,7 +6,7 @@ import (
 	"github.com/gomods/athens/pkg/storage"
 )
 
-// Fetcher fetches module from an upstream source
+// Fetcher fetches module from an upstream source.
 type Fetcher interface {
 	// Fetch downloads the sources from an upstream and returns the corresponding
 	// .info, .mod, and .zip files.

pkg/module/filter.go

@@ -3,6 +3,7 @@ package module
 import (
 	"bufio"
 	"os"
+	"path/filepath"
 	"strconv"
 	"strings"
 
@@ -14,15 +15,15 @@ var (
 	versionSeparator = "."
 )
 
-// Filter is a filter of modules
+// Filter is a filter of modules.
 type Filter struct {
 	root     ruleNode
 	filePath string
 }
 
-// NewFilter creates new filter based on rules defined in a configuration file
+// NewFilter creates new filter based on rules defined in a configuration file.
-// WARNING: this is not concurrently safe
+// WARNING: this is not concurrently safe.
-// Configuration consists of two operations: + for include and - for exclude
+// Configuration consists of two operations: + for include and - for exclude:
 // e.g.
 //   - github.com/a
 //   - github.com/a/b
@@ -33,7 +34,7 @@ type Filter struct {
 //	-
 //	+ github.com/a
 //
-// will exclude all items from communication except github.com/a
+// will exclude all items from communication except github.com/a.
 func NewFilter(filterFilePath string) (*Filter, error) {
 	// Do not return an error if the file path is empty
 	// Do not attempt to parse it as well.
@@ -42,10 +43,9 @@ func NewFilter(filterFilePath string) (*Filter, error) {
 	}
 
 	return initFromConfig(filterFilePath)
-
 }
 
-// AddRule adds rule for specified path
+// AddRule adds rule for specified path.
 func (f *Filter) AddRule(path string, qualifiers []string, rule FilterRule) {
 	f.ensurePath(path)
 
@@ -70,7 +70,7 @@ func (f *Filter) AddRule(path string, qualifiers []string, rule FilterRule) {
 	latest.next[last] = rn
 }
 
-// Rule returns the filter rule to be applied to the given path
+// Rule returns the filter rule to be applied to the given path.
 func (f *Filter) Rule(path, version string) FilterRule {
 	segs := getPathSegments(path)
 	rule := f.getAssociatedRule(version, segs...)
@@ -145,7 +145,6 @@ func initFromConfig(filePath string) (*Filter, error) {
 	f.root = rn
 
 	for idx, line := range lines {
-
 		// Ignore newline
 		if len(line) == 0 {
 			continue
@@ -160,7 +159,7 @@ func initFromConfig(filePath string) (*Filter, error) {
 		}
 
 		ruleSign := strings.TrimSpace(split[0])
-		rule := Default
+		var rule FilterRule
 		switch ruleSign {
 		case "+":
 			rule = Include
@@ -195,11 +194,11 @@ func initFromConfig(filePath string) (*Filter, error) {
 
 // matches checks if the given version matches the given qualifier.
 // Qualifiers can be:
-// - plain versions
+// - plain versions.
-// - v1.2.3 enables v1.2.3
+// - v1.2.3 enables v1.2.3.
-// - ~1.2.3: enables 1.2.x  which are at least 1.2.3
+// - ~1.2.3: enables 1.2.x  which are at least 1.2.3.
-// - ^1.2.3: enables 1.x.x which are at least 1.2.3
+// - ^1.2.3: enables 1.x.x which are at least 1.2.3.
-// - <1.2.3: enables everything lower than 1.2.3 includes 1.2.2 and 0.58.9 as well
+// - <1.2.3: enables everything lower than 1.2.3 includes 1.2.2 and 0.58.9 as well.
 func matches(version, qualifier string) bool {
 	if len(qualifier) < 2 || len(version) < 1 {
 		return false
@@ -297,7 +296,7 @@ func newRule(r FilterRule) ruleNode {
 func getConfigLines(filterFile string) ([]string, error) {
 	const op errors.Op = "module.getConfigLines"
 
-	f, err := os.Open(filterFile)
+	f, err := os.Open(filepath.Clean(filterFile))
 	if err != nil {
 		return nil, errors.E(op, err)
 	}

pkg/module/filterRule.go

@@ -1,16 +1,16 @@
 package module
 
-// FilterRule defines behavior of module communication
+// FilterRule defines behavior of module communication.
 type FilterRule int
 
 const (
-	// Default filter rule does not alter default/parent behavior
+	// Default filter rule does not alter default/parent behavior.
 	Default FilterRule = iota
-	// Include treats modules the usual way
+	// Include treats modules the usual way.
-	// Used for reverting Exclude of parent path
+	// Used for reverting Exclude of parent path.
 	Include
-	// Exclude filter rule excludes package and its children from communication
+	// Exclude filter rule excludes package and its children from communication.
 	Exclude
-	// Direct filter rule forces the package to be fetched directly from upstream proxy
+	// Direct filter rule forces the package to be fetched directly from upstream proxy.
 	Direct
 )

pkg/module/go_get_fetcher.go

@@ -35,7 +35,7 @@ type goModule struct {
 	GoModSum string `json:"goModSum"` // checksum for go.mod (as in go.sum)
 }
 
-// NewGoGetFetcher creates fetcher which uses go get tool to fetch modules
+// NewGoGetFetcher creates fetcher which uses go get tool to fetch modules.
 func NewGoGetFetcher(goBinaryName, gogetDir string, envVars []string, fs afero.Fs) (Fetcher, error) {
 	const op errors.Op = "module.NewGoGetFetcher"
 	if err := validGoBinary(goBinaryName); err != nil {
@@ -64,7 +64,7 @@ func (g *goGetFetcher) Fetch(ctx context.Context, mod, ver string) (*storage.Ver
 	sourcePath := filepath.Join(goPathRoot, "src")
 	modPath := filepath.Join(sourcePath, getRepoDirName(mod, ver))
 	if err := g.fs.MkdirAll(modPath, os.ModeDir|os.ModePerm); err != nil {
-		clearFiles(g.fs, goPathRoot)
+		_ = clearFiles(g.fs, goPathRoot)
 		return nil, errors.E(op, err)
 	}
 
@@ -72,14 +72,13 @@ func (g *goGetFetcher) Fetch(ctx context.Context, mod, ver string) (*storage.Ver
 		ctx,
 		g.goBinaryName,
 		g.envVars,
-		g.fs,
 		goPathRoot,
 		modPath,
 		mod,
 		ver,
 	)
 	if err != nil {
-		clearFiles(g.fs, goPathRoot)
+		_ = clearFiles(g.fs, goPathRoot)
 		return nil, errors.E(op, err)
 	}
 
@@ -116,7 +115,6 @@ func downloadModule(
 	ctx context.Context,
 	goBinaryName string,
 	envVars []string,
-	fs afero.Fs,
 	gopath,
 	repoRoot,
 	module,
@@ -137,7 +135,7 @@ func downloadModule(
 
 	err := cmd.Run()
 	if err != nil {
-		err = fmt.Errorf("%v: %s", err, stderr)
+		err = fmt.Errorf("%w: %s", err, stderr)
 		var m goModule
 		if jsonErr := json.NewDecoder(stdout).Decode(&m); jsonErr != nil {
 			return goModule{}, errors.E(op, err)
@@ -165,17 +163,17 @@ func isLimitHit(o string) bool {
 }
 
 // getRepoDirName takes a raw repository URI and a version and creates a directory name that the
-// repository contents can be put into
+// repository contents can be put into.
 func getRepoDirName(repoURI, version string) string {
-	escapedURI := strings.Replace(repoURI, "/", "-", -1)
+	escapedURI := strings.ReplaceAll(repoURI, "/", "-")
 	return fmt.Sprintf("%s-%s", escapedURI, version)
 }
 
 func validGoBinary(name string) error {
 	const op errors.Op = "module.validGoBinary"
 	err := exec.Command(name).Run()
-	_, ok := err.(*exec.ExitError)
+	eErr := &exec.ExitError{}
-	if err != nil && !ok {
+	if err != nil && !errors.AsErr(err, &eErr) {
 		return errors.E(op, err)
 	}
 	return nil

pkg/module/go_vcs_lister.go

@@ -28,7 +28,7 @@ type vcsLister struct {
 	fs        afero.Fs
 }
 
-// NewVCSLister creates an UpstreamLister which uses VCS to fetch a list of available versions
+// NewVCSLister creates an UpstreamLister which uses VCS to fetch a list of available versions.
 func NewVCSLister(goBinPath string, env []string, fs afero.Fs) UpstreamLister {
 	return &vcsLister{
 		goBinPath: goBinPath,
@@ -39,13 +39,13 @@ func NewVCSLister(goBinPath string, env []string, fs afero.Fs) UpstreamLister {
 
 func (l *vcsLister) List(ctx context.Context, module string) (*storage.RevInfo, []string, error) {
 	const op errors.Op = "vcsLister.List"
-	ctx, span := observ.StartSpan(ctx, op.String())
+	_, span := observ.StartSpan(ctx, op.String())
 	defer span.End()
 	tmpDir, err := afero.TempDir(l.fs, "", "go-list")
 	if err != nil {
 		return nil, nil, errors.E(op, err)
 	}
-	defer l.fs.RemoveAll(tmpDir)
+	defer func() { _ = l.fs.RemoveAll(tmpDir) }()
 
 	cmd := exec.Command(
 		l.goBinPath,
@@ -62,12 +62,12 @@ func (l *vcsLister) List(ctx context.Context, module string) (*storage.RevInfo,
 	if err != nil {
 		return nil, nil, errors.E(op, err)
 	}
-	defer clearFiles(l.fs, gopath)
+	defer func() { _ = clearFiles(l.fs, gopath) }()
 	cmd.Env = prepareEnv(gopath, l.env)
 
 	err = cmd.Run()
 	if err != nil {
-		err = fmt.Errorf("%v: %s", err, stderr)
+		err = fmt.Errorf("%w: %s", err, stderr)
 		// as of now, we can't recognize between a true NotFound
 		// and an unexpected error, so we choose the more
 		// hopeful path of NotFound. This way the Go command

pkg/module/prepare_env.go

@@ -9,7 +9,7 @@ import (
 
 // prepareEnv will return all the appropriate
 // environment variables for a Go Command to run
-// successfully (such as GOPATH, GOCACHE, PATH etc)
+// successfully (such as GOPATH, GOCACHE, PATH etc).
 func prepareEnv(gopath string, envVars []string) []string {
 	gopathEnv := fmt.Sprintf("GOPATH=%s", gopath)
 	cacheEnv := fmt.Sprintf("GOCACHE=%s", filepath.Join(gopath, "cache"))

pkg/module/zip_read_closer.go

@@ -14,10 +14,10 @@ type zipReadCloser struct {
 	goPath string
 }
 
-// Close closes the zip file handle and clears up disk space used by the underlying disk ref
+// Close closes the zip file handle and clears up disk space used by the underlying disk ref.
-// It is the caller's responsibility to call this method to free up utilized disk space
+// It is the caller's responsibility to call this method to free up utilized disk space.
 func (rc *zipReadCloser) Close() error {
-	rc.zip.Close()
+	_ = rc.zip.Close()
 	return clearFiles(rc.fs, rc.goPath)
 }
 
@@ -25,8 +25,8 @@ func (rc *zipReadCloser) Read(p []byte) (n int, err error) {
 	return rc.zip.Read(p)
 }
 
-// clearFiles deletes all data from the given fs at path root
+// clearFiles deletes all data from the given fs at path root.
-// This function must be called when zip is closed to cleanup the entire GOPATH created by the diskref
+// This function must be called when zip is closed to cleanup the entire GOPATH created by the diskref.
 func clearFiles(fs afero.Fs, root string) error {
 	const op errors.Op = "module.ClearFiles"
 	// This is required because vgo ensures dependencies are read-only
@@ -36,7 +36,7 @@ func clearFiles(fs afero.Fs, root string) error {
 		if err != nil {
 			return err
 		}
-		return fs.Chmod(path, 0770)
+		return fs.Chmod(path, 0o770)
 	}
 	err := afero.Walk(fs, root, walkFn)
 	if err != nil {

pkg/observ/observ.go

@@ -13,16 +13,16 @@ import (
 
 // RegisterExporter determines the type of TraceExporter service for exporting traces from opencensus
 // User can choose from multiple tracing services (datadog, jaegar)
-// RegisterExporter returns the 'Flush' function for that particular tracing service
+// RegisterExporter returns the 'Flush' function for that particular tracing service.
-func RegisterExporter(traceExporter, URL, service, ENV string) (func(), error) {
+func RegisterExporter(traceExporter, url, service, env string) (func(), error) {
 	const op errors.Op = "observ.RegisterExporter"
 	switch traceExporter {
 	case "jaeger":
-		return registerJaegerExporter(URL, service, ENV)
+		return registerJaegerExporter(url, service, env)
 	case "datadog":
-		return registerDatadogExporter(URL, service, ENV)
+		return registerDatadogExporter(url, service, env)
 	case "stackdriver":
-		return registerStackdriverExporter(URL, ENV)
+		return registerStackdriverExporter(url, env)
 	case "":
 		return nil, errors.E(op, "Exporter not specified. Traces won't be exported")
 	default:
@@ -32,14 +32,14 @@ func RegisterExporter(traceExporter, URL, service, ENV string) (func(), error) {
 
 // registerJaegerExporter creates a jaeger exporter for exporting traces to opencensus.
 // Currently uses the 'TraceExporter' variable in the config file.
-// It should in the future have a nice sampling rate defined
+// It should in the future have a nice sampling rate defined.
-func registerJaegerExporter(URL, service, ENV string) (func(), error) {
+func registerJaegerExporter(url, service, env string) (func(), error) {
 	const op errors.Op = "observ.registerJaegarExporter"
-	if URL == "" {
+	if url == "" {
 		return nil, errors.E(op, "Exporter URL is empty. Traces won't be exported")
 	}
 	ex, err := jaeger.NewExporter(jaeger.Options{
-		Endpoint: URL,
+		Endpoint: url,
 		Process: jaeger.Process{
 			ServiceName: service,
 			Tags: []jaeger.Tag{
@@ -53,41 +53,41 @@ func registerJaegerExporter(URL, service, ENV string) (func(), error) {
 	if err != nil {
 		return nil, errors.E(op, err)
 	}
-	traceRegisterExporter(ex, ENV)
+	traceRegisterExporter(ex, env)
 	return ex.Flush, nil
 }
 
-func traceRegisterExporter(exporter trace.Exporter, ENV string) {
+func traceRegisterExporter(exporter trace.Exporter, env string) {
 	trace.RegisterExporter(exporter)
-	if ENV == "development" {
+	if env == "development" {
 		trace.ApplyConfig(trace.Config{DefaultSampler: trace.AlwaysSample()})
 	}
 }
 
 // registerDatadogTracerExporter creates a datadog exporter.
 // Currently uses the 'TraceExporter' variable in the config file.
-func registerDatadogExporter(URL, service, ENV string) (func(), error) {
+func registerDatadogExporter(url, service, env string) (func(), error) {
 	ex := datadog.NewExporter(
 		datadog.Options{
-			TraceAddr: URL,
+			TraceAddr: url,
 			Service:   service,
 		})
-	traceRegisterExporter(ex, ENV)
+	traceRegisterExporter(ex, env)
 	return ex.Stop, nil
 }
 
-func registerStackdriverExporter(projectID, ENV string) (func(), error) {
+func registerStackdriverExporter(projectID, env string) (func(), error) {
 	const op errors.Op = "observ.registerStackdriverExporter"
 	ex, err := stackdriver.NewExporter(stackdriver.Options{ProjectID: projectID})
 	if err != nil {
 		return nil, errors.E(op, err)
 	}
-	traceRegisterExporter(ex, ENV)
+	traceRegisterExporter(ex, env)
 	return ex.Flush, nil
 }
 
 // StartSpan takes in a Context Interface and opName and starts a span. It returns the new attached ObserverContext
-// and span
+// and span.
 func StartSpan(ctx context.Context, op string) (context.Context, *trace.Span) {
 	return trace.StartSpan(ctx, op)
 }

pkg/observ/stats.go

@@ -15,10 +15,10 @@ import (
 )
 
 // RegisterStatsExporter determines the type of StatsExporter service for exporting stats from Opencensus
-// Currently it supports: prometheus
+// Currently it supports: prometheus.
 func RegisterStatsExporter(r *mux.Router, statsExporter, service string) (func(), error) {
 	const op errors.Op = "observ.RegisterStatsExporter"
-	var stop = func() {}
+	stop := func() {}
 	var err error
 	switch statsExporter {
 	case "prometheus":
@@ -38,7 +38,7 @@ func RegisterStatsExporter(r *mux.Router, statsExporter, service string) (func()
 	default:
 		return nil, errors.E(op, fmt.Sprintf("StatsExporter %s not supported. Please open PR or an issue at github.com/gomods/athens", statsExporter))
 	}
-	if err := registerViews(); err != nil {
+	if err = registerViews(); err != nil {
 		return nil, errors.E(op, err)
 	}
 
@@ -89,7 +89,7 @@ func registerStatsStackDriverExporter(projectID string) (func(), error) {
 	return sd.Flush, nil
 }
 
-// registerViews register stats which should be collected in Athens
+// registerViews register stats which should be collected in Athens.
 func registerViews() error {
 	const op errors.Op = "observ.registerViews"
 	if err := view.Register(

pkg/paths/decode.go

@@ -19,8 +19,9 @@ func DecodePath(encoding string) (path string, err error) {
 	return path, nil
 }
 
-// Ripped from cmd/go
+// Ripped from cmd/go.
 func decodeString(encoding string) (string, bool) {
+	//nolint:prealloc
 	var buf []byte
 
 	bang := false

pkg/paths/path.go

@@ -9,7 +9,7 @@ import (
 	"github.com/gorilla/mux"
 )
 
-// GetModule gets the module from the path of a ?go-get=1 request
+// GetModule gets the module from the path of a ?go-get=1 request.
 func GetModule(r *http.Request) (string, error) {
 	const op errors.Op = "paths.GetModule"
 	module := mux.Vars(r)["module"]
@@ -19,7 +19,7 @@ func GetModule(r *http.Request) (string, error) {
 	return DecodePath(module)
 }
 
-// GetVersion gets the version from the path of a ?go-get=1 request
+// GetVersion gets the version from the path of a ?go-get=1 request.
 func GetVersion(r *http.Request) (string, error) {
 	const op errors.Op = "paths.GetVersion"
 
@@ -31,13 +31,13 @@ func GetVersion(r *http.Request) (string, error) {
 }
 
 // AllPathParams holds the module and version in the path of a ?go-get=1
-// request
+// request.
 type AllPathParams struct {
 	Module  string `json:"module"`
 	Version string `json:"version"`
 }
 
-// GetAllParams fetches the path params from r and returns them
+// GetAllParams fetches the path params from r and returns them.
 func GetAllParams(r *http.Request) (*AllPathParams, error) {
 	const op errors.Op = "paths.GetAllParams"
 	mod, err := GetModule(r)
@@ -54,7 +54,7 @@ func GetAllParams(r *http.Request) (*AllPathParams, error) {
 }
 
 // MatchesPattern reports whether the path prefix of target matches
-// pattern (as defined by path.Match)
+// pattern (as defined by path.Match).
 //
 // This tries to keep the same behavior as GOPRIVATE/GONOPROXY/GONOSUMDB,
 // and is adopted from:

pkg/requestid/requestid.go

@@ -3,18 +3,18 @@ package requestid
 import "context"
 
 // HeaderKey is the header key that athens uses
-// to pass request ids into logs and outbound requests
+// to pass request ids into logs and outbound requests.
 const HeaderKey = "Athens-Request-ID"
 
 type key struct{}
 
-// SetInContext sets the given requestID into the context
+// SetInContext sets the given requestID into the context.
 func SetInContext(ctx context.Context, id string) context.Context {
 	return context.WithValue(ctx, key{}, id)
 }
 
 // FromContext returns a requestID from the context or an empty
-// string if not found
+// string if not found.
 func FromContext(ctx context.Context) string {
 	id, _ := ctx.Value(key{}).(string)
 	return id

pkg/stash/stasher.go

@@ -19,7 +19,7 @@ import (
 // what was requested, this is helpful if what was requested
 // was a descriptive version such as a branch name or a full commit sha.
 type Stasher interface {
-	Stash(ctx context.Context, mod string, ver string) (string, error)
+	Stash(ctx context.Context, mod, ver string) (string, error)
 }
 
 // Wrapper helps extend the main stasher's functionality with addons.
@@ -46,7 +46,7 @@ type stasher struct {
 
 func (s *stasher) Stash(ctx context.Context, mod, ver string) (string, error) {
 	const op errors.Op = "stasher.Stash"
-	_, span := observ.StartSpan(ctx, op.String())
+	ctx, span := observ.StartSpan(ctx, op.String())
 	defer span.End()
 	log.EntryFromContext(ctx).Debugf("saving %s@%s to storage...", mod, ver)
 
@@ -58,7 +58,7 @@ func (s *stasher) Stash(ctx context.Context, mod, ver string) (string, error) {
 	if err != nil {
 		return "", errors.E(op, err)
 	}
-	defer v.Zip.Close()
+	defer func() { _ = v.Zip.Close() }()
 	if v.Semver != ver {
 		exists, err := s.checker.Exists(ctx, mod, v.Semver)
 		if err != nil {

pkg/stash/with_azureblob.go

@@ -132,8 +132,8 @@ func (s *azblobLock) acquireLease(ctx context.Context, blobURL azblob.BlockBlobU
 	_, err := blobURL.Upload(tctx, bytes.NewReader([]byte{1}), azblob.BlobHTTPHeaders{}, nil, azblob.BlobAccessConditions{})
 	if err != nil {
 		// if the blob is already leased we will get http.StatusPreconditionFailed while writing to that blob
-		stgErr, ok := err.(azblob.StorageError)
+		var stgErr azblob.StorageError
-		if !ok || stgErr.Response().StatusCode != http.StatusPreconditionFailed {
+		if !errors.AsErr(err, &stgErr) || stgErr.Response().StatusCode != http.StatusPreconditionFailed {
 			return "", errors.E(op, err)
 		}
 	}
@@ -147,7 +147,8 @@ func (s *azblobLock) acquireLease(ctx context.Context, blobURL azblob.BlockBlobU
 		res, err := blobURL.AcquireLease(tctx, leaseID.String(), 15, azblob.ModifiedAccessConditions{})
 		if err != nil {
 			// if the blob is already leased we will get http.StatusConflict - wait and try again
-			if stgErr, ok := err.(azblob.StorageError); ok && stgErr.Response().StatusCode == http.StatusConflict {
+			var stgErr azblob.StorageError
+			if ok := errors.AsErr(err, &stgErr); ok && stgErr.Response().StatusCode == http.StatusConflict {
 				select {
 				case <-time.After(1 * time.Second):
 					continue

pkg/stash/with_etcd.go

@@ -8,7 +8,7 @@ import (
 	"github.com/gomods/athens/pkg/errors"
 	"github.com/gomods/athens/pkg/observ"
 	"github.com/gomods/athens/pkg/storage"
-	"go.etcd.io/etcd/client/v3"
+	clientv3 "go.etcd.io/etcd/client/v3"
 	"go.etcd.io/etcd/client/v3/concurrency"
 	"golang.org/x/sync/errgroup"
 )

pkg/stash/with_redis.go

@@ -13,14 +13,14 @@ import (
 	"github.com/gomods/athens/pkg/storage"
 )
 
-// RedisLogger mirrors github.com/go-redis/redis/v8/internal.Logging
+// RedisLogger mirrors github.com/go-redis/redis/v8/internal.Logging.
 type RedisLogger interface {
 	Printf(ctx context.Context, format string, v ...interface{})
 }
 
 // WithRedisLock returns a distributed singleflight
 // using a redis cluster. If it cannot connect, it will return an error.
-func WithRedisLock(l RedisLogger, endpoint string, password string, checker storage.Checker, lockConfig *config.RedisLockConfig) (Wrapper, error) {
+func WithRedisLock(l RedisLogger, endpoint, password string, checker storage.Checker, lockConfig *config.RedisLockConfig) (Wrapper, error) {
 	redis.SetLogger(l)
 
 	const op errors.Op = "stash.WithRedisLock"

pkg/stash/with_redis_sentinel.go

@@ -10,7 +10,7 @@ import (
 )
 
 // WithRedisSentinelLock returns a distributed singleflight
-// with a redis cluster that utilizes sentinel for quorum and failover
+// with a redis cluster that utilizes sentinel for quorum and failover.
 func WithRedisSentinelLock(l RedisLogger, endpoints []string, master, password string, checker storage.Checker, lockConfig *config.RedisLockConfig) (Wrapper, error) {
 	redis.SetLogger(l)
 

pkg/storage/azureblob/azureblob.go

@@ -15,14 +15,6 @@ import (
 	"github.com/gomods/athens/pkg/storage"
 )
 
-type client interface {
-	UploadWithContext(ctx context.Context, path, contentType string, content io.Reader) error
-	BlobExists(ctx context.Context, path string) (bool, error)
-	ReadBlob(ctx context.Context, path string) (io.ReadCloser, error)
-	ListBlobs(ctx context.Context, prefix string) ([]string, error)
-	DeleteBlob(ctx context.Context, path string) error
-}
-
 type azureBlobStoreClient struct {
 	containerURL *azblob.ContainerURL
 }
@@ -45,13 +37,13 @@ func newBlobStoreClient(accountURL *url.URL, accountName, accountKey, containerN
 }
 
 // Storage implements (github.com/gomods/athens/pkg/storage).Saver and
-// also provides a function to fetch the location of a module
+// also provides a function to fetch the location of a module.
 type Storage struct {
 	client  *azureBlobStoreClient
 	timeout time.Duration
 }
 
-// New creates a new azure blobs storage
+// New creates a new azure blobs storage.
 func New(conf *config.AzureBlobConfig, timeout time.Duration) (*Storage, error) {
 	const op errors.Op = "azureblob.New"
 	u, err := url.Parse(fmt.Sprintf("https://%s.blob.core.windows.net", conf.AccountName))
@@ -65,7 +57,7 @@ func New(conf *config.AzureBlobConfig, timeout time.Duration) (*Storage, error)
 	return &Storage{client: cl, timeout: timeout}, nil
 }
 
-// BlobExists checks if a particular blob exists in the container
+// BlobExists checks if a particular blob exists in the container.
 func (c *azureBlobStoreClient) BlobExists(ctx context.Context, path string) (bool, error) {
 	const op errors.Op = "azureblob.BlobExists"
 	// TODO: Any better way of doing this ?
@@ -73,10 +65,8 @@ func (c *azureBlobStoreClient) BlobExists(ctx context.Context, path string) (boo
 	_, err := blobURL.GetProperties(ctx, azblob.BlobAccessConditions{})
 	if err != nil {
 		var serr azblob.StorageError
-		var ok bool
+		if !errors.AsErr(err, &serr) {
-
+			return false, errors.E(op, fmt.Errorf("error in casting to azure error type %w", err))
-		if serr, ok = err.(azblob.StorageError); !ok {
-			return false, errors.E(op, fmt.Errorf("Error in casting to azure error type %v", err))
 		}
 		if serr.Response().StatusCode == http.StatusNotFound {
 			return false, nil
@@ -85,10 +75,9 @@ func (c *azureBlobStoreClient) BlobExists(ctx context.Context, path string) (boo
 		return false, errors.E(op, err)
 	}
 	return true, nil
-
 }
 
-// ReadBlob returns a storage.SizeReadCloser for the contents of a blob
+// ReadBlob returns a storage.SizeReadCloser for the contents of a blob.
 func (c *azureBlobStoreClient) ReadBlob(ctx context.Context, path string) (storage.SizeReadCloser, error) {
 	const op errors.Op = "azureblob.ReadBlob"
 	blobURL := c.containerURL.NewBlockBlobURL(path)
@@ -101,7 +90,7 @@ func (c *azureBlobStoreClient) ReadBlob(ctx context.Context, path string) (stora
 	return storage.NewSizer(rc, size), nil
 }
 
-// ListBlobs will list all blobs which has the given prefix
+// ListBlobs will list all blobs which has the given prefix.
 func (c *azureBlobStoreClient) ListBlobs(ctx context.Context, prefix string) ([]string, error) {
 	const op errors.Op = "azureblob.ListBlobs"
 	var blobs []string
@@ -122,7 +111,7 @@ func (c *azureBlobStoreClient) ListBlobs(ctx context.Context, prefix string) ([]
 	return blobs, nil
 }
 
-// DeleteBlob deletes the blob with the given path
+// DeleteBlob deletes the blob with the given path.
 func (c *azureBlobStoreClient) DeleteBlob(ctx context.Context, path string) error {
 	const op errors.Op = "azureblob.DeleteBlob"
 	blobURL := c.containerURL.NewBlockBlobURL(path)
@@ -133,7 +122,7 @@ func (c *azureBlobStoreClient) DeleteBlob(ctx context.Context, path string) erro
 	return nil
 }
 
-// UploadWithContext uploads a blob to the container
+// UploadWithContext uploads a blob to the container.
 func (c *azureBlobStoreClient) UploadWithContext(ctx context.Context, path, contentType string, content io.Reader) error {
 	const op errors.Op = "azureblob.UploadWithContext"
 	ctx, span := observ.StartSpan(ctx, op.String())

pkg/storage/azureblob/cataloger.go

@@ -12,8 +12,8 @@ import (
 	"github.com/gomods/athens/pkg/paths"
 )
 
-// Catalog implements the (./pkg/storage).Catalog interface
+// Catalog implements the (./pkg/storage).Catalog interface.
-// It returns a list of versions, if any, for a given module
+// It returns a list of versions, if any, for a given module.
 func (s *Storage) Catalog(ctx context.Context, token string, pageSize int) ([]paths.AllPathParams, string, error) {
 	const op errors.Op = "azblob.Catalog"
 	ctx, span := observ.StartSpan(ctx, op.String())

pkg/storage/azureblob/checker.go

@@ -9,8 +9,8 @@ import (
 )
 
 // Exists implements the (./pkg/storage).Checker interface
-// returning true if the module at version exists in storage
+// returning true if the module at version exists in storage.
-func (s *Storage) Exists(ctx context.Context, module string, version string) (bool, error) {
+func (s *Storage) Exists(ctx context.Context, module, version string) (bool, error) {
 	const op errors.Op = "azureblob.Exists"
 	ctx, span := observ.StartSpan(ctx, op.String())
 	defer span.End()

pkg/storage/azureblob/deleter.go

@@ -11,7 +11,7 @@ import (
 // Delete implements the (./pkg/storage).Deleter interface and
 // removes a version of a module from storage. Returning ErrNotFound
 // if the version does not exist.
-func (s *Storage) Delete(ctx context.Context, module string, version string) error {
+func (s *Storage) Delete(ctx context.Context, module, version string) error {
 	const op errors.Op = "azureblob.Delete"
 	ctx, span := observ.StartSpan(ctx, op.String())
 	defer span.End()

pkg/storage/azureblob/getter.go

@@ -11,8 +11,8 @@ import (
 	"github.com/gomods/athens/pkg/storage"
 )
 
-// Info implements the (./pkg/storage).Getter interface
+// Info implements the (./pkg/storage).Getter interface.
-func (s *Storage) Info(ctx context.Context, module string, version string) ([]byte, error) {
+func (s *Storage) Info(ctx context.Context, module, version string) ([]byte, error) {
 	const op errors.Op = "azureblob.Info"
 	ctx, span := observ.StartSpan(ctx, op.String())
 	defer span.End()
@@ -43,8 +43,8 @@ func (s *Storage) Info(ctx context.Context, module string, version string) ([]by
 	return infoBytes, nil
 }
 
-// GoMod implements the (./pkg/storage).Getter interface
+// GoMod implements the (./pkg/storage).Getter interface.
-func (s *Storage) GoMod(ctx context.Context, module string, version string) ([]byte, error) {
+func (s *Storage) GoMod(ctx context.Context, module, version string) ([]byte, error) {
 	const op errors.Op = "azureblob.GoMod"
 	ctx, span := observ.StartSpan(ctx, op.String())
 	defer span.End()
@@ -64,7 +64,7 @@ func (s *Storage) GoMod(ctx context.Context, module string, version string) ([]b
 
 	modBytes, err := io.ReadAll(modReader)
 	if err != nil {
-		return nil, errors.E(op, fmt.Errorf("could not get new reader for mod file: %s", err), errors.M(module), errors.V(version))
+		return nil, errors.E(op, fmt.Errorf("could not get new reader for mod file: %w", err), errors.M(module), errors.V(version))
 	}
 
 	err = modReader.Close()
@@ -75,8 +75,8 @@ func (s *Storage) GoMod(ctx context.Context, module string, version string) ([]b
 	return modBytes, nil
 }
 
-// Zip implements the (./pkg/storage).Getter interface
+// Zip implements the (./pkg/storage).Getter interface.
-func (s *Storage) Zip(ctx context.Context, module string, version string) (storage.SizeReadCloser, error) {
+func (s *Storage) Zip(ctx context.Context, module, version string) (storage.SizeReadCloser, error) {
 	const op errors.Op = "azureblob.Zip"
 	ctx, span := observ.StartSpan(ctx, op.String())
 	defer span.End()

pkg/storage/azureblob/lister.go

@@ -8,8 +8,8 @@ import (
 	"github.com/gomods/athens/pkg/observ"
 )
 
-// List implements the (./pkg/storage).Lister interface
+// List implements the (./pkg/storage).Lister interface.
-// It returns a list of versions, if any, for a given module
+// It returns a list of versions, if any, for a given module.
 func (s *Storage) List(ctx context.Context, module string) ([]string, error) {
 	const op errors.Op = "azureblob.List"
 	ctx, span := observ.StartSpan(ctx, op.String())

pkg/storage/backend.go

@@ -1,6 +1,6 @@
 package storage
 
-// Backend is a complete storage backend (i.e. file system, database) implementation - a lister, reader and saver
+// Backend is a complete storage backend (i.e. file system, database) implementation - a lister, reader and saver.
 type Backend interface {
 	Lister
 	Getter

pkg/storage/cataloger.go

@@ -6,7 +6,7 @@ import (
 	"github.com/gomods/athens/pkg/paths"
 )
 
-// Cataloger is the interface that lists all the modules and version contained in the storage
+// Cataloger is the interface that lists all the modules and version contained in the storage.
 type Cataloger interface {
 	// Catalog gets all the modules / versions.
 	Catalog(ctx context.Context, token string, pageSize int) ([]paths.AllPathParams, string, error)

pkg/storage/checker.go

@@ -6,14 +6,14 @@ import (
 	"github.com/gomods/athens/pkg/errors"
 )
 
-// Checker is the interface that checks if the version of the module exists
+// Checker is the interface that checks if the version of the module exists.
 type Checker interface {
 	// Exists checks whether or not module in specified version is present
-	// in the backing storage
+	// in the backing storage.
 	Exists(ctx context.Context, module, version string) (bool, error)
 }
 
-// WithChecker wraps the backend with a Checker implementaiton
+// WithChecker wraps the backend with a Checker implementation.
 func WithChecker(strg Backend) Checker {
 	if checker, ok := strg.(Checker); ok {
 		return checker

pkg/storage/compliance/tests.go

@@ -6,7 +6,6 @@ import (
 	"fmt"
 	"io"
 	"math/rand"
-	"sort"
 	"testing"
 
 	"github.com/gomods/athens/pkg/errors"
@@ -26,7 +25,6 @@ func RunTests(t *testing.T, b storage.Backend, clearBackend func() error) {
 	testGet(t, b)
 	testExists(t, b)
 	testShouldNotExist(t, b)
-	// testCatalog(t, b)
 }
 
 // testNotFound ensures that a storage Backend
@@ -209,49 +207,6 @@ func testDelete(t *testing.T, b storage.Backend) {
 	require.Equal(t, false, exists)
 }
 
-func testCatalog(t *testing.T, b storage.Backend) {
-	cs, ok := b.(storage.Cataloger)
-	if !ok {
-		t.Skip()
-	}
-	ctx := context.Background()
-
-	mock := getMockModule()
-	zipBts, _ := io.ReadAll(mock.Zip)
-	modname := "github.com/gomods/testCatalogModule"
-	for i := 0; i < 6; i++ {
-		ver := fmt.Sprintf("v1.2.%04d", i)
-		b.Save(ctx, modname, ver, mock.Mod, bytes.NewReader(zipBts), mock.Info)
-
-		defer b.Delete(ctx, modname, ver)
-	}
-
-	allres, next, err := cs.Catalog(ctx, "", 5)
-
-	require.NoError(t, err)
-	require.Equal(t, 5, len(allres))
-
-	res, next, err := cs.Catalog(ctx, next, 50)
-	allres = append(allres, res...)
-	require.NoError(t, err)
-	require.Equal(t, 1, len(res))
-	require.Equal(t, "", next)
-
-	sort.Slice(allres, func(i, j int) bool {
-		if allres[i].Module == allres[j].Module {
-			return allres[i].Version < allres[j].Version
-		}
-		return allres[i].Module < allres[j].Module
-	})
-	require.Equal(t, modname, allres[0].Module)
-	require.Equal(t, "v1.2.0000", allres[0].Version)
-	require.Equal(t, "v1.2.0004", allres[4].Version)
-
-	for i := 1; i < len(allres); i++ {
-		require.NotEqual(t, allres[i].Version, allres[i-1].Version)
-	}
-}
-
 func getMockModule() *storage.Version {
 	return &storage.Version{
 		Info: []byte("123"),

pkg/storage/deleter.go

@@ -2,7 +2,7 @@ package storage
 
 import "context"
 
-// Deleter deletes module metadata and its source from underlying storage
+// Deleter deletes module metadata and its source from underlying storage.
 type Deleter interface {
 	// Delete must return ErrNotFound if the module/version are not
 	// found.

pkg/storage/external/client.go

@@ -20,7 +20,7 @@ type service struct {
 	c   *http.Client
 }
 
-// NewClient returns an external storage client
+// NewClient returns an external storage client.
 func NewClient(url string, c *http.Client) storage.Backend {
 	if c == nil {
 		c = &http.Client{}
@@ -93,7 +93,7 @@ func (s *service) Save(ctx context.Context, mod, ver string, modFile []byte, zip
 	mw := multipart.NewWriter(pw)
 	go func() {
 		err := upload(mw, modFile, info, zip)
-		pw.CloseWithError(err)
+		_ = pw.CloseWithError(err)
 	}()
 	req, err := http.NewRequestWithContext(ctx, http.MethodPost, url, pr)
 	if err != nil {
@@ -104,8 +104,8 @@ func (s *service) Save(ctx context.Context, mod, ver string, modFile []byte, zip
 	if err != nil {
 		return errors.E(op, err)
 	}
-	defer resp.Body.Close()
+	defer func() { _ = resp.Body.Close() }()
-	if resp.StatusCode != 200 {
+	if resp.StatusCode != http.StatusOK {
 		bts, _ := io.ReadAll(resp.Body)
 		return errors.E(op, fmt.Errorf("unexpected status code: %v - body: %s", resp.StatusCode, bts), resp.StatusCode)
 	}
@@ -118,35 +118,35 @@ func (s *service) Delete(ctx context.Context, mod, ver string) error {
 	if err != nil {
 		return errors.E(op, err)
 	}
-	defer body.Close()
+	defer func() { _ = body.Close() }()
 	return nil
 }
 
 func upload(mw *multipart.Writer, mod, info []byte, zip io.Reader) error {
-	defer mw.Close()
+	defer func() { _ = mw.Close() }()
 	infoW, err := mw.CreateFormFile("mod.info", "mod.info")
 	if err != nil {
-		return fmt.Errorf("error creating info file: %v", err)
+		return fmt.Errorf("error creating info file: %w", err)
 	}
 	_, err = infoW.Write(info)
 	if err != nil {
-		return fmt.Errorf("error writing info file: %v", err)
+		return fmt.Errorf("error writing info file: %w", err)
 	}
 	modW, err := mw.CreateFormFile("mod.mod", "mod.mod")
 	if err != nil {
-		return fmt.Errorf("error creating mod file: %v", err)
+		return fmt.Errorf("error creating mod file: %w", err)
 	}
 	_, err = modW.Write(mod)
 	if err != nil {
-		return fmt.Errorf("error writing mod file: %v", err)
+		return fmt.Errorf("error writing mod file: %w", err)
 	}
 	zipW, err := mw.CreateFormFile("mod.zip", "mod.zip")
 	if err != nil {
-		return fmt.Errorf("error creating zip file: %v", err)
+		return fmt.Errorf("error creating zip file: %w", err)
 	}
 	_, err = io.Copy(zipW, zip)
 	if err != nil {
-		return fmt.Errorf("error writing zip file: %v", err)
+		return fmt.Errorf("error writing zip file: %w", err)
 	}
 	return nil
 }
@@ -174,9 +174,9 @@ func (s *service) doRequest(ctx context.Context, method, mod, ver, ext string) (
 	if err != nil {
 		return nil, 0, errors.E(op, err)
 	}
-	if resp.StatusCode != 200 {
+	if resp.StatusCode != http.StatusOK {
 		body, _ := io.ReadAll(resp.Body)
-		resp.Body.Close()
+		_ = resp.Body.Close()
 		return nil, 0, errors.E(op, fmt.Errorf("none 200 status code: %v - body: %s", resp.StatusCode, body), resp.StatusCode)
 	}
 	var size int64

pkg/storage/external/server.go

@@ -17,7 +17,7 @@ import (
 
 // NewServer takes a storage.Backend implementation of your
 // choice, and returns a new http.Handler that Athens can
-// reach out to for storage operations
+// reach out to for storage operations.
 func NewServer(strg storage.Backend) http.Handler {
 	r := mux.NewRouter()
 	r.HandleFunc(download.PathList, func(w http.ResponseWriter, r *http.Request) {
@@ -27,12 +27,12 @@ func NewServer(strg storage.Backend) http.Handler {
 			http.Error(w, err.Error(), errors.Kind(err))
 			return
 		}
-		fmt.Fprintf(w, "%s", strings.Join(list, "\n"))
+		_, _ = fmt.Fprintf(w, "%s", strings.Join(list, "\n"))
 	}).Methods(http.MethodGet)
 	r.HandleFunc(download.PathVersionInfo, func(w http.ResponseWriter, r *http.Request) {
 		params, err := paths.GetAllParams(r)
 		if err != nil {
-			http.Error(w, err.Error(), 400)
+			http.Error(w, err.Error(), http.StatusBadRequest)
 			return
 		}
 		info, err := strg.Info(r.Context(), params.Module, params.Version)
@@ -40,12 +40,12 @@ func NewServer(strg storage.Backend) http.Handler {
 			http.Error(w, err.Error(), errors.Kind(err))
 			return
 		}
-		w.Write(info)
+		_, _ = w.Write(info)
 	}).Methods(http.MethodGet)
 	r.HandleFunc(download.PathVersionModule, func(w http.ResponseWriter, r *http.Request) {
 		params, err := paths.GetAllParams(r)
 		if err != nil {
-			http.Error(w, err.Error(), 400)
+			http.Error(w, err.Error(), http.StatusBadRequest)
 			return
 		}
 		mod, err := strg.GoMod(r.Context(), params.Module, params.Version)
@@ -53,12 +53,12 @@ func NewServer(strg storage.Backend) http.Handler {
 			http.Error(w, err.Error(), errors.Kind(err))
 			return
 		}
-		w.Write(mod)
+		_, _ = w.Write(mod)
 	}).Methods(http.MethodGet)
 	r.HandleFunc(download.PathVersionZip, func(w http.ResponseWriter, r *http.Request) {
 		params, err := paths.GetAllParams(r)
 		if err != nil {
-			http.Error(w, err.Error(), 400)
+			http.Error(w, err.Error(), http.StatusBadRequest)
 			return
 		}
 		zip, err := strg.Zip(r.Context(), params.Module, params.Version)
@@ -66,52 +66,52 @@ func NewServer(strg storage.Backend) http.Handler {
 			http.Error(w, err.Error(), errors.Kind(err))
 			return
 		}
-		defer zip.Close()
+		defer func() { _ = zip.Close() }()
 		w.Header().Set("Content-Length", strconv.FormatInt(zip.Size(), 10))
-		io.Copy(w, zip)
+		_, _ = io.Copy(w, zip)
 	}).Methods(http.MethodGet)
 	r.HandleFunc("/{module:.+}/@v/{version}.save", func(w http.ResponseWriter, r *http.Request) {
 		params, err := paths.GetAllParams(r)
 		if err != nil {
-			http.Error(w, err.Error(), 400)
+			http.Error(w, err.Error(), http.StatusBadRequest)
 			return
 		}
 		err = r.ParseMultipartForm(zip.MaxZipFile + zip.MaxGoMod)
 		if err != nil {
-			http.Error(w, err.Error(), 400)
+			http.Error(w, err.Error(), http.StatusBadRequest)
 			return
 		}
 		infoFile, _, err := r.FormFile("mod.info")
 		if err != nil {
-			http.Error(w, err.Error(), 400)
+			http.Error(w, err.Error(), http.StatusBadRequest)
 			return
 		}
-		defer infoFile.Close()
+		defer func() { _ = infoFile.Close() }()
 		info, err := io.ReadAll(infoFile)
 		if err != nil {
-			http.Error(w, err.Error(), 400)
+			http.Error(w, err.Error(), http.StatusBadRequest)
 			return
 		}
 		modReader, _, err := r.FormFile("mod.mod")
 		if err != nil {
-			http.Error(w, err.Error(), 400)
+			http.Error(w, err.Error(), http.StatusBadRequest)
 			return
 		}
-		defer modReader.Close()
+		defer func() { _ = modReader.Close() }()
 		modFile, err := io.ReadAll(modReader)
 		if err != nil {
-			http.Error(w, err.Error(), 400)
+			http.Error(w, err.Error(), http.StatusBadRequest)
 			return
 		}
 		modZ, _, err := r.FormFile("mod.zip")
 		if err != nil {
-			http.Error(w, err.Error(), 400)
+			http.Error(w, err.Error(), http.StatusBadRequest)
 			return
 		}
-		defer modZ.Close()
+		defer func() { _ = modZ.Close() }()
 		err = strg.Save(r.Context(), params.Module, params.Version, modFile, modZ, info)
 		if err != nil {
-			http.Error(w, err.Error(), 400)
+			http.Error(w, err.Error(), http.StatusBadRequest)
 			return
 		}
 	}).Methods(http.MethodPost)
@@ -119,7 +119,7 @@ func NewServer(strg storage.Backend) http.Handler {
 	r.HandleFunc("/{module:.+}/@v/{version}.delete", func(w http.ResponseWriter, r *http.Request) {
 		params, err := paths.GetAllParams(r)
 		if err != nil {
-			http.Error(w, err.Error(), 400)
+			http.Error(w, err.Error(), http.StatusBadRequest)
 			return
 		}
 		err = strg.Delete(r.Context(), params.Module, params.Version)

pkg/storage/fs/cataloger.go

@@ -15,11 +15,11 @@ import (
 
 const tokenSeparator = "|"
 
-// Catalog implements the (./pkg/storage).Cataloger interface
+// Catalog implements the (./pkg/storage).Cataloger interface.
-// It returns a list of modules and versions contained in the storage
+// It returns a list of modules and versions contained in the storage.
 func (s *storageImpl) Catalog(ctx context.Context, token string, pageSize int) ([]paths.AllPathParams, string, error) {
 	const op errors.Op = "fs.Catalog"
-	ctx, span := observ.StartSpan(ctx, op.String())
+	_, span := observ.StartSpan(ctx, op.String())
 	defer span.End()
 
 	fromModule, fromVersion, err := modVerFromToken(token)
@@ -41,7 +41,7 @@ func (s *storageImpl) Catalog(ctx context.Context, token string, pageSize int) (
 
 			m, version := filepath.Split(modVer)
 			module := filepath.Clean(m)
-			module = strings.Replace(module, string(os.PathSeparator), "/", -1)
+			module = strings.ReplaceAll(module, string(os.PathSeparator), "/")
 
 			if fromModule != "" && module < fromModule { // it is ok to land on the same module
 				return nil
@@ -60,7 +60,7 @@ func (s *storageImpl) Catalog(ctx context.Context, token string, pageSize int) (
 		}
 		return nil
 	})
-	if err != nil && err != io.EOF {
+	if err != nil && !errors.IsErr(err, io.EOF) {
 		return nil, "", errors.E(op, err, errors.KindUnexpected)
 	}
 

pkg/storage/fs/checker.go

@@ -9,14 +9,13 @@ import (
 	"github.com/spf13/afero"
 )
 
-func (v *storageImpl) Exists(ctx context.Context, module, version string) (bool, error) {
+func (s *storageImpl) Exists(ctx context.Context, module, version string) (bool, error) {
 	const op errors.Op = "fs.Exists"
-	ctx, span := observ.StartSpan(ctx, op.String())
+	_, span := observ.StartSpan(ctx, op.String())
 	defer span.End()
-	versionedPath := v.versionLocation(module, version)
+	versionedPath := s.versionLocation(module, version)
-
-	files, err := afero.ReadDir(v.filesystem, versionedPath)
 
+	files, err := afero.ReadDir(s.filesystem, versionedPath)
 	if err != nil {
 		if os.IsNotExist(err) {
 			return false, nil

pkg/storage/fs/deleter.go

@@ -8,17 +8,17 @@ import (
 )
 
 // Delete removes a specific version of a module.
-func (v *storageImpl) Delete(ctx context.Context, module, version string) error {
+func (s *storageImpl) Delete(ctx context.Context, module, version string) error {
 	const op errors.Op = "fs.Delete"
 	ctx, span := observ.StartSpan(ctx, op.String())
 	defer span.End()
-	versionedPath := v.versionLocation(module, version)
+	versionedPath := s.versionLocation(module, version)
-	exists, err := v.Exists(ctx, module, version)
+	exists, err := s.Exists(ctx, module, version)
 	if err != nil {
 		return errors.E(op, err, errors.M(module), errors.V(version))
 	}
 	if !exists {
 		return errors.E(op, errors.M(module), errors.V(version), errors.KindNotFound)
 	}
-	return v.filesystem.RemoveAll(versionedPath)
+	return s.filesystem.RemoveAll(versionedPath)
 }

pkg/storage/fs/fs.go

@@ -21,17 +21,16 @@ func (s *storageImpl) moduleLocation(module string) string {
 
 func (s *storageImpl) versionLocation(module, version string) string {
 	return filepath.Join(s.moduleLocation(module), version)
-
 }
 
 // NewStorage returns a new ListerSaver implementation that stores
-// everything under rootDir
+// everything under rootDir.
-// If the root directory does not exist an error is returned
+// If the root directory does not exist an error is returned.
 func NewStorage(rootDir string, filesystem afero.Fs) (storage.Backend, error) {
 	const op errors.Op = "fs.NewStorage"
 	exists, err := afero.Exists(filesystem, rootDir)
 	if err != nil {
-		return nil, errors.E(op, fmt.Errorf("could not check if root directory `%s` exists: %s", rootDir, err))
+		return nil, errors.E(op, fmt.Errorf("could not check if root directory `%s` exists: %w", rootDir, err))
 	}
 	if !exists {
 		return nil, errors.E(op, fmt.Errorf("root directory `%s` does not exist", rootDir))

pkg/storage/fs/getter.go

@@ -11,12 +11,12 @@ import (
 	"github.com/spf13/afero"
 )
 
-func (v *storageImpl) Info(ctx context.Context, module, version string) ([]byte, error) {
+func (s *storageImpl) Info(ctx context.Context, module, version string) ([]byte, error) {
 	const op errors.Op = "fs.Info"
-	ctx, span := observ.StartSpan(ctx, op.String())
+	_, span := observ.StartSpan(ctx, op.String())
 	defer span.End()
-	versionedPath := v.versionLocation(module, version)
+	versionedPath := s.versionLocation(module, version)
-	info, err := afero.ReadFile(v.filesystem, filepath.Join(versionedPath, version+".info"))
+	info, err := afero.ReadFile(s.filesystem, filepath.Join(versionedPath, version+".info"))
 	if err != nil {
 		return nil, errors.E(op, errors.M(module), errors.V(version), errors.KindNotFound)
 	}
@@ -24,12 +24,12 @@ func (v *storageImpl) Info(ctx context.Context, module, version string) ([]byte,
 	return info, nil
 }
 
-func (v *storageImpl) GoMod(ctx context.Context, module, version string) ([]byte, error) {
+func (s *storageImpl) GoMod(ctx context.Context, module, version string) ([]byte, error) {
 	const op errors.Op = "fs.GoMod"
-	ctx, span := observ.StartSpan(ctx, op.String())
+	_, span := observ.StartSpan(ctx, op.String())
 	defer span.End()
-	versionedPath := v.versionLocation(module, version)
+	versionedPath := s.versionLocation(module, version)
-	mod, err := afero.ReadFile(v.filesystem, filepath.Join(versionedPath, "go.mod"))
+	mod, err := afero.ReadFile(s.filesystem, filepath.Join(versionedPath, "go.mod"))
 	if err != nil {
 		return nil, errors.E(op, errors.M(module), errors.V(version), errors.KindNotFound)
 	}
@@ -37,13 +37,13 @@ func (v *storageImpl) GoMod(ctx context.Context, module, version string) ([]byte
 	return mod, nil
 }
 
-func (v *storageImpl) Zip(ctx context.Context, module, version string) (storage.SizeReadCloser, error) {
+func (s *storageImpl) Zip(ctx context.Context, module, version string) (storage.SizeReadCloser, error) {
 	const op errors.Op = "fs.Zip"
-	ctx, span := observ.StartSpan(ctx, op.String())
+	_, span := observ.StartSpan(ctx, op.String())
 	defer span.End()
-	versionedPath := v.versionLocation(module, version)
+	versionedPath := s.versionLocation(module, version)
 
-	src, err := v.filesystem.OpenFile(filepath.Join(versionedPath, "source.zip"), os.O_RDONLY, 0666)
+	src, err := s.filesystem.OpenFile(filepath.Join(versionedPath, "source.zip"), os.O_RDONLY, 0o666)
 	if err != nil {
 		return nil, errors.E(op, errors.M(module), errors.V(version), errors.KindNotFound)
 	}
@@ -53,15 +53,3 @@ func (v *storageImpl) Zip(ctx context.Context, module, version string) (storage.
 	}
 	return storage.NewSizer(src, fi.Size()), nil
 }
-
-func (v *storageImpl) ZipSize(ctx context.Context, module, version string) (int64, error) {
-	const op errors.Op = "fs.ZipFileSize"
-	ctx, span := observ.StartSpan(ctx, op.String())
-	defer span.End()
-	versionedPath := v.versionLocation(module, version)
-	fi, err := v.filesystem.Stat(filepath.Join(versionedPath))
-	if err != nil {
-		return 0, errors.E(op, err, errors.M(module), errors.V(version), errors.KindNotFound)
-	}
-	return fi.Size(), nil
-}

pkg/storage/fs/lister.go

@@ -11,12 +11,12 @@ import (
 	"golang.org/x/mod/semver"
 )
 
-func (l *storageImpl) List(ctx context.Context, module string) ([]string, error) {
+func (s *storageImpl) List(ctx context.Context, module string) ([]string, error) {
 	const op errors.Op = "fs.List"
-	ctx, span := observ.StartSpan(ctx, op.String())
+	_, span := observ.StartSpan(ctx, op.String())
 	defer span.End()
-	loc := l.moduleLocation(module)
+	loc := s.moduleLocation(module)
-	fileInfos, err := afero.ReadDir(l.filesystem, loc)
+	fileInfos, err := afero.ReadDir(s.filesystem, loc)
 	if err != nil {
 		if os.IsNotExist(err) {
 			return []string{}, nil

pkg/storage/fs/saver.go

@@ -13,37 +13,37 @@ import (
 
 func (s *storageImpl) Save(ctx context.Context, module, version string, mod []byte, zip io.Reader, info []byte) error {
 	const op errors.Op = "fs.Save"
-	ctx, span := observ.StartSpan(ctx, op.String())
+	_, span := observ.StartSpan(ctx, op.String())
 	defer span.End()
 	dir := s.versionLocation(module, version)
 
-	// NB: the process's umask is subtracted from the permissions below,
+	// NB: The process's umask is subtracted from the permissions below,
-	// so a umask of for example 0077 allows directories and files to be
+	// so an umask of for example 0077 allows directories and files to be
-	// created with mode 0700 / 0600, i.e. not world- or group-readable
+	// created with mode 0700 / 0600, i.e. not world- or group-readable.
 
-	// make the versioned directory to hold the go.mod and the zipfile
+	// Make the versioned directory to hold the go.mod and the zipfile.
-	if err := s.filesystem.MkdirAll(dir, 0777); err != nil {
+	if err := s.filesystem.MkdirAll(dir, 0o777); err != nil {
 		return errors.E(op, err, errors.M(module), errors.V(version))
 	}
 
-	// write the go.mod file
+	// Write the go.mod file.
-	if err := afero.WriteFile(s.filesystem, filepath.Join(dir, "go.mod"), mod, 0666); err != nil {
+	if err := afero.WriteFile(s.filesystem, filepath.Join(dir, "go.mod"), mod, 0o666); err != nil {
 		return errors.E(op, err, errors.M(module), errors.V(version))
 	}
 
-	// write the zipfile
+	// Write the zipfile.
-	f, err := s.filesystem.OpenFile(filepath.Join(dir, "source.zip"), os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0666)
+	f, err := s.filesystem.OpenFile(filepath.Join(dir, "source.zip"), os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0o666)
 	if err != nil {
 		return errors.E(op, err, errors.M(module), errors.V(version))
 	}
-	defer f.Close()
+	defer func() { _ = f.Close() }()
 	_, err = io.Copy(f, zip)
 	if err != nil {
 		return errors.E(op, err, errors.M(module), errors.V(version))
 	}
 
 	// write the info file
-	err = afero.WriteFile(s.filesystem, filepath.Join(dir, version+".info"), info, 0666)
+	err = afero.WriteFile(s.filesystem, filepath.Join(dir, version+".info"), info, 0o666)
 	if err != nil {
 		return errors.E(op, err)
 	}

pkg/storage/gcp/cataloger.go

@@ -14,7 +14,7 @@ import (
 )
 
 // Catalog implements the (./pkg/storage).Catalog interface
-// It returns a list of versions, if any, for a given module
+// It returns a list of versions, if any, for a given module.
 func (s *Storage) Catalog(ctx context.Context, token string, pageSize int) ([]paths.AllPathParams, string, error) {
 	const op errors.Op = "gcp.Catalog"
 	ctx, span := observ.StartSpan(ctx, op.String())

pkg/storage/gcp/checker.go

@@ -11,7 +11,7 @@ import (
 )
 
 // Exists implements the (./pkg/storage).Checker interface
-// returning true if the module at version exists in storage
+// returning true if the module at version exists in storage.
 func (s *Storage) Exists(ctx context.Context, module, version string) (bool, error) {
 	const op errors.Op = "gcp.Exists"
 	ctx, span := observ.StartSpan(ctx, op.String())
@@ -21,7 +21,7 @@ func (s *Storage) Exists(ctx context.Context, module, version string) (bool, err
 	var count int
 	for {
 		attrs, err := it.Next()
-		if err == iterator.Done {
+		if errors.IsErr(err, iterator.Done) {
 			break
 		}
 		if err != nil {

pkg/storage/gcp/gcp.go

@@ -13,7 +13,7 @@ import (
 	"google.golang.org/api/option"
 )
 
-// Storage implements the (./pkg/storage).Backend interface
+// Storage implements the (./pkg/storage).Backend interface.
 type Storage struct {
 	bucket  *storage.BucketHandle
 	timeout time.Duration
@@ -34,8 +34,8 @@ func New(ctx context.Context, gcpConf *config.GCPConfig, timeout time.Duration)
 		return nil, errors.E(op, err)
 	}
 
-	if _, err := s.bucket.Attrs(ctx); err != nil {
+	if _, err = s.bucket.Attrs(ctx); err != nil {
-		if err == storage.ErrBucketNotExist {
+		if errors.IsErr(err, storage.ErrBucketNotExist) {
 			return nil, errors.E(op, "You must manually create a storage bucket for Athens, see https://cloud.google.com/storage/docs/creating-buckets#storage-create-bucket-console")
 		}
 		return nil, errors.E(op, err)
@@ -48,21 +48,21 @@ func New(ctx context.Context, gcpConf *config.GCPConfig, timeout time.Duration)
 // this is so that the unit tests can use this to create their own short-lived buckets.
 func newClient(ctx context.Context, gcpConf *config.GCPConfig, timeout time.Duration) (*Storage, error) {
 	const op errors.Op = "gcp.newClient"
-	opts := []option.ClientOption{}
+	var opts []option.ClientOption
 	if gcpConf.JSONKey != "" {
 		key, err := base64.StdEncoding.DecodeString(gcpConf.JSONKey)
 		if err != nil {
-			return nil, errors.E(op, fmt.Errorf("could not decode base64 json key: %v", err))
+			return nil, errors.E(op, fmt.Errorf("could not decode base64 json key: %w", err))
 		}
 		creds, err := google.CredentialsFromJSON(ctx, key, storage.ScopeReadWrite)
 		if err != nil {
-			return nil, errors.E(op, fmt.Errorf("could not get GCS credentials: %v", err))
+			return nil, errors.E(op, fmt.Errorf("could not get GCS credentials: %w", err))
 		}
 		opts = append(opts, option.WithCredentials(creds))
 	}
 	s, err := storage.NewClient(ctx, opts...)
 	if err != nil {
-		return nil, errors.E(op, fmt.Errorf("could not create new storage client: %s", err))
+		return nil, errors.E(op, fmt.Errorf("could not create new storage client: %w", err))
 	}
 
 	return &Storage{

pkg/storage/gcp/getter.go

@@ -12,7 +12,7 @@ import (
 	pkgstorage "github.com/gomods/athens/pkg/storage"
 )
 
-// Info implements Getter
+// Info implements Getter.
 func (s *Storage) Info(ctx context.Context, module, version string) ([]byte, error) {
 	const op errors.Op = "gcp.Info"
 	ctx, span := observ.StartSpan(ctx, op.String())
@@ -22,14 +22,14 @@ func (s *Storage) Info(ctx context.Context, module, version string) ([]byte, err
 		return nil, errors.E(op, err, getErrorKind(err), errors.M(module), errors.V(version))
 	}
 	infoBytes, err := io.ReadAll(infoReader)
-	infoReader.Close()
+	_ = infoReader.Close()
 	if err != nil {
 		return nil, errors.E(op, err, errors.M(module), errors.V(version))
 	}
 	return infoBytes, nil
 }
 
-// GoMod implements Getter
+// GoMod implements Getter.
 func (s *Storage) GoMod(ctx context.Context, module, version string) ([]byte, error) {
 	const op errors.Op = "gcp.GoMod"
 	ctx, span := observ.StartSpan(ctx, op.String())
@@ -39,15 +39,15 @@ func (s *Storage) GoMod(ctx context.Context, module, version string) ([]byte, er
 		return nil, errors.E(op, err, getErrorKind(err), errors.M(module), errors.V(version))
 	}
 	modBytes, err := io.ReadAll(modReader)
-	modReader.Close()
+	_ = modReader.Close()
 	if err != nil {
-		return nil, errors.E(op, fmt.Errorf("could not get new reader for mod file: %s", err), errors.M(module), errors.V(version))
+		return nil, errors.E(op, fmt.Errorf("could not get new reader for mod file: %w", err), errors.M(module), errors.V(version))
 	}
 
 	return modBytes, nil
 }
 
-// Zip implements Getter
+// Zip implements Getter.
 func (s *Storage) Zip(ctx context.Context, module, version string) (pkgstorage.SizeReadCloser, error) {
 	const op errors.Op = "gcp.Zip"
 	ctx, span := observ.StartSpan(ctx, op.String())
@@ -56,11 +56,11 @@ func (s *Storage) Zip(ctx context.Context, module, version string) (pkgstorage.S
 	if err != nil {
 		return nil, errors.E(op, err, getErrorKind(err), errors.M(module), errors.V(version))
 	}
-	return pkgstorage.NewSizer(zipReader, zipReader.Size()), nil
+	return pkgstorage.NewSizer(zipReader, zipReader.Attrs.Size), nil
 }
 
 func getErrorKind(err error) int {
-	if err == storage.ErrObjectNotExist {
+	if errors.IsErr(err, storage.ErrObjectNotExist) {
 		return errors.KindNotFound
 	}
 	return errors.KindUnexpected

pkg/storage/gcp/lister.go

@@ -10,8 +10,8 @@ import (
 	"google.golang.org/api/iterator"
 )
 
-// List implements the (./pkg/storage).Lister interface
+// List implements the (./pkg/storage).Lister interface.
-// It returns a list of versions, if any, for a given module
+// It returns a list of versions, if any, for a given module.
 func (s *Storage) List(ctx context.Context, module string) ([]string, error) {
 	const op errors.Op = "gcp.List"
 	ctx, span := observ.StartSpan(ctx, op.String())
@@ -22,7 +22,7 @@ func (s *Storage) List(ctx context.Context, module string) ([]string, error) {
 	paths := []string{}
 	for {
 		attrs, err := it.Next()
-		if err == iterator.Done {
+		if errors.IsErr(err, iterator.Done) {
 			break
 		}
 		if err != nil {