Config improvements - rename file & remove default (#1103)

* Rename config.dev.toml to config-example.toml

* Updating helm docs to point to the new helm chart repository (#1102)

* Updating helm docs to point to the new helm chart repository

Fixes https://github.com/gomods/athens/issues/1099
Follow-up to https://github.com/gomods/athens/pull/1097/files

* fixes

* Helm chart: Fix ingress setup (#1086)

* Helm chart: Fix ingress setup

The ingress part of the Helm chart contained references to
not-existing templates and values. Additionally, the deployment used
some no longer available health-check URLs which prevented it from
being marked as ready.

* Make readiness and liveness paths depend on the image.tag

* Add read from .athens.toml (from pwd, then home)

* Remove config lookup from HOME

* Revert "Rename config.dev.toml to config-example.toml"

This reverts commit 9c02956406.

* Fix comment

config.dev.toml

@@ -2,6 +2,9 @@
 # Most properties can be overridden with environment variables specified in this file
 # Most properties also have defaults (mentioned in this file) if they are not set in either the config file or the corresponding environment variable
 
+# If you put this file where you start Athens from as "athens.toml", athens will use it when starting.
+# You can also start athens with -config_file as command line argument to point out a config file.
+
 # GoBinary returns the path to the go binary to use. This value can be a name of a binary in your PATH, or the full path
 # Defaults to "go"
 # Env override: GO_BINARY_PATH

pkg/config/config.go

@@ -13,6 +13,8 @@ import (
 	validator "gopkg.in/go-playground/validator.v9"
 )
 
+const defaultConfigFile = "athens.toml"
+
 // Config provides configuration values for all components
 type Config struct {
 	TimeoutConf
@@ -47,14 +49,22 @@ type Config struct {
 // Load loads the config from a file.
 // If file is not present returns default config
 func Load(configFile string) (*Config, error) {
-	if configFile == "" {
+	// User explicitly specified a config file
-		log.Print("config file not provided - using default settings")
+	if configFile != "" {
-		return createDefault(), nil
+		return ParseConfigFile(configFile)
 	}
-	return ParseConfigFile(configFile)
+
+	// There is a config in the current directory
+	if fi, err := os.Stat(defaultConfigFile); err == nil {
+		return ParseConfigFile(fi.Name())
+	}
+
+	// Use default values
+	log.Println("Running dev mode with default settings, consult config when you're ready to run in production")
+	return defaultConfig(), nil
 }
 
-func createDefault() *Config {
+func defaultConfig() *Config {
 	return &Config{
 		GoBinary:         "go",
 		GoEnv:            "development",

pkg/config/config_test.go

@@ -413,7 +413,7 @@ func TestDefaultConfigMatchesConfigFile(t *testing.T) {
 		t.Errorf("Unable to parse example config file: %+v", err)
 	}
 
-	defConf := createDefault()
+	defConf := defaultConfig()
 
 	ignoreStorageOpts := cmpopts.IgnoreTypes(&StorageConfig{})
 	ignoreGoEnvOpts := cmpopts.IgnoreFields(Config{}, "GoEnv")