ref: upstream lister and it's impl to module pkg (#1309)

pkg/download/protocol.go

@@ -9,6 +9,7 @@ import (
 
 	"github.com/gomods/athens/pkg/download/mode"
 	"github.com/gomods/athens/pkg/errors"
+	"github.com/gomods/athens/pkg/module"
 	"github.com/gomods/athens/pkg/observ"
 	"github.com/gomods/athens/pkg/stash"
 	"github.com/gomods/athens/pkg/storage"
@@ -40,7 +41,7 @@ type Wrapper func(Protocol) Protocol
 type Opts struct {
 	Storage      storage.Backend
 	Stasher      stash.Stasher
-	Lister       UpstreamLister
+	Lister       module.UpstreamLister
 	DownloadFile *mode.DownloadFile
 }
 
@@ -65,7 +66,7 @@ type protocol struct {
 	df      *mode.DownloadFile
 	storage storage.Backend
 	stasher stash.Stasher
-	lister  UpstreamLister
+	lister  module.UpstreamLister
 }
 
 func (p *protocol) List(ctx context.Context, mod string) ([]string, error) {

pkg/download/protocol_test.go

@@ -46,7 +46,7 @@ func getDP(t *testing.T) Protocol {
 		t.Fatal(err)
 	}
 	st := stash.New(mf, s)
-	return New(&Opts{s, st, NewVCSLister(goBin, goProxy, fs), nil})
+	return New(&Opts{s, st, module.NewVCSLister(goBin, goProxy, fs), nil})
 }
 
 type listTest struct {

pkg/download/upstream_lister.go

@@ -1,95 +0,0 @@
-package download
-
-import (
-	"bytes"
-	"context"
-	"encoding/json"
-	"fmt"
-	"os/exec"
-	"time"
-
-	"github.com/gomods/athens/pkg/config"
-	"github.com/gomods/athens/pkg/errors"
-	"github.com/gomods/athens/pkg/module"
-	"github.com/gomods/athens/pkg/observ"
-	"github.com/gomods/athens/pkg/storage"
-	"github.com/spf13/afero"
-)
-
-// UpstreamLister retrieves a list of available module versions from upstream
-// i.e. VCS, and a Storage backend.
-type UpstreamLister interface {
-	List(ctx context.Context, mod string) (*storage.RevInfo, []string, error)
-}
-
-type listResp struct {
-	Path     string
-	Version  string
-	Versions []string `json:",omitempty"`
-	Time     time.Time
-}
-
-type vcsLister struct {
-	goBinPath string
-	goProxy   string
-	fs        afero.Fs
-}
-
-func (l *vcsLister) List(ctx context.Context, mod string) (*storage.RevInfo, []string, error) {
-	const op errors.Op = "vcsLister.List"
-	ctx, 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)
-
-	cmd := exec.Command(
-		l.goBinPath,
-		"list", "-m", "-versions", "-json",
-		config.FmtModVer(mod, "latest"),
-	)
-	cmd.Dir = tmpDir
-	stdout := &bytes.Buffer{}
-	stderr := &bytes.Buffer{}
-	cmd.Stdout = stdout
-	cmd.Stderr = stderr
-
-	gopath, err := afero.TempDir(l.fs, "", "athens")
-	if err != nil {
-		return nil, nil, errors.E(op, err)
-	}
-	defer module.ClearFiles(l.fs, gopath)
-	cmd.Env = module.PrepareEnv(gopath, l.goProxy)
-
-	err = cmd.Run()
-	if err != nil {
-		err = fmt.Errorf("%v: %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
-		// will not log en error and we still get to log
-		// what happened here if someone wants to dig in more.
-		// Once, https://github.com/golang/go/issues/30134 is
-		// resolved, we can hopefully differentiate.
-		return nil, nil, errors.E(op, err, errors.KindNotFound)
-	}
-
-	var lr listResp
-	err = json.NewDecoder(stdout).Decode(&lr)
-	if err != nil {
-		return nil, nil, errors.E(op, err)
-	}
-	rev := storage.RevInfo{
-		Time:    lr.Time,
-		Version: lr.Version,
-	}
-	return &rev, lr.Versions, nil
-}
-
-// NewVCSLister creates an UpstreamLister which uses VCS to fetch a list of available versions
-func NewVCSLister(goBinPath, goProxy string, fs afero.Fs) UpstreamLister {
-	return &vcsLister{goBinPath: goBinPath, goProxy: goProxy, fs: fs}
-}