feat(config): add --configFile argument to specify custom config file

It will also look by default to `/etc/sablier/` then `$XDG_CONFIG_HOME` then `$HOME/.config/` and then `.`.

Closes #91

.gitignore

@@ -1,3 +1,3 @@
 .devcontainer
-config.yaml
+sablier.yaml
 ./plugins/traefik/e2e/kubeconfig.yaml

Dockerfile

@@ -16,9 +16,9 @@ RUN make ${TARGETOS}/${TARGETARCH}
 
 FROM alpine
 
-COPY --from=build /go/src/sablier/sablier* /go/bin/sablier
+COPY --from=build /go/src/sablier/sablier* /etc/sablier/sablier
 
 EXPOSE 10000
 
-ENTRYPOINT [ "/go/bin/sablier" ]
+ENTRYPOINT [ "/etc/sablier/sablier" ]
 CMD [ "start", "--provider.name=docker"]

cmd/root.go

@@ -15,10 +15,11 @@ import (
 
 const (
 	// The name of our config file, without the file extension because viper supports many different config file languages.
-	defaultConfigFilename = "config"
+	defaultConfigFilename = "sablier"
 )
 
 var conf = config.NewConfig()
+var cfgFile string
 
 func Execute() {
 	cmd := NewRootCommand()
@@ -39,6 +40,8 @@ It provides an integrations with multiple reverse proxies and different loading
 		},
 	}
 
+	rootCmd.PersistentFlags().StringVar(&cfgFile, "configFile", "", "Config file path. If not defined, looks for sablier.(yml|yaml|toml) in /etc/sablier/ > $XDG_CONFIG_HOME > $HOME/.config/ and current directory")
+
 	startCmd := newStartCommand()
 	// Provider flags
 	startCmd.Flags().StringVar(&conf.Provider.Name, "provider.name", "docker", fmt.Sprintf("Provider to use to manage containers %v", config.GetProviders()))
@@ -85,10 +88,15 @@ func initializeConfig(cmd *cobra.Command) error {
 	// Set the base name of the config file, without the file extension.
 	v.SetConfigName(defaultConfigFilename)
 
-	// Set as many paths as you like where viper should look for the
+	v.AddConfigPath("/etc/sablier/")
-	// config file. We are only looking in the current working directory.
+	v.AddConfigPath("$XDG_CONFIG_HOME")
+	v.AddConfigPath("$HOME/.config/")
 	v.AddConfigPath(".")
 
+	if cfgFile != "" {
+		v.SetConfigFile(cfgFile)
+	}
+
 	// Attempt to read the config file, gracefully ignoring errors
 	// caused by a config file not being found. Return an error
 	// if we cannot parse the config file.
@@ -96,6 +104,9 @@ func initializeConfig(cmd *cobra.Command) error {
 		// It's okay if there isn't a config file
 		if _, ok := err.(viper.ConfigFileNotFoundError); !ok {
 			return err
+		} else if cfgFile != "" {
+			// But if we explicitely defined the config file it should return the error
+			return err
 		}
 	}
 

cmd/root_test.go

@@ -18,24 +18,13 @@ import (
 )
 
 func TestPrecedence(t *testing.T) {
-	// Run the tests in a temporary directory
-	tmpDir := os.TempDir()
 	testDir, err := os.Getwd()
 	require.NoError(t, err, "error getting the current working directory")
-	defer os.Chdir(testDir)
-	err = os.Chdir(tmpDir)
-	require.NoError(t, err, "error changing to the temporary test directory")
 
 	// CHANGE `startCmd` behavior to only print the config, this is for testing purposes only
 	newStartCommand = mockStartCommand
 
 	t.Run("config file", func(t *testing.T) {
-		configB, err := os.ReadFile(filepath.Join(testDir, "testdata", "config.yml"))
-		require.NoError(t, err, "error reading test config file")
-		err = ioutil.WriteFile(filepath.Join(tmpDir, "config.yml"), configB, 0644)
-		require.NoError(t, err, "error writing test config file")
-		defer os.Remove(filepath.Join(tmpDir, "config.yml"))
-
 		wantConfig, err := ioutil.ReadFile(filepath.Join(testDir, "testdata", "config_yaml_wanted.json"))
 		require.NoError(t, err, "error reading test config file")
 
@@ -43,7 +32,10 @@ func TestPrecedence(t *testing.T) {
 		cmd := NewRootCommand()
 		output := &bytes.Buffer{}
 		cmd.SetOut(output)
-		cmd.SetArgs([]string{"start"})
+		cmd.SetArgs([]string{
+			"--configFile", filepath.Join(testDir, "testdata", "config.yml"),
+			"start",
+		})
 		cmd.Execute()
 
 		gotOutput := output.String()
@@ -52,13 +44,6 @@ func TestPrecedence(t *testing.T) {
 	})
 
 	t.Run("env var", func(t *testing.T) {
-		// 1. Load Config file for precedence assertions
-		configB, err := os.ReadFile(filepath.Join(testDir, "testdata", "config.yml"))
-		require.NoError(t, err, "error reading test config file")
-		err = ioutil.WriteFile(filepath.Join(tmpDir, "config.yml"), configB, 0644)
-		require.NoError(t, err, "error writing test config file")
-		defer os.Remove(filepath.Join(tmpDir, "config.yml"))
-
 		setEnvsFromFile(filepath.Join(testDir, "testdata", "config.env"))
 		defer unsetEnvsFromFile(filepath.Join(testDir, "testdata", "config.env"))
 
@@ -69,7 +54,10 @@ func TestPrecedence(t *testing.T) {
 		cmd := NewRootCommand()
 		output := &bytes.Buffer{}
 		cmd.SetOut(output)
-		cmd.SetArgs([]string{"start"})
+		cmd.SetArgs([]string{
+			"--configFile", filepath.Join(testDir, "testdata", "config.yml"),
+			"start",
+		})
 		cmd.Execute()
 
 		gotOutput := output.String()
@@ -78,14 +66,6 @@ func TestPrecedence(t *testing.T) {
 	})
 
 	t.Run("flag", func(t *testing.T) {
-		// 1. Load Config file for precedence assertions
-		configB, err := os.ReadFile(filepath.Join(testDir, "testdata", "config.yml"))
-		require.NoError(t, err, "error reading test config file")
-		err = ioutil.WriteFile(filepath.Join(tmpDir, "config.yml"), configB, 0644)
-		require.NoError(t, err, "error writing test config file")
-		defer os.Remove(filepath.Join(tmpDir, "config.yml"))
-
-		// 2. Load envs variable for precedence assertions
 		setEnvsFromFile(filepath.Join(testDir, "testdata", "config.env"))
 		defer unsetEnvsFromFile(filepath.Join(testDir, "testdata", "config.env"))
 
@@ -97,6 +77,7 @@ func TestPrecedence(t *testing.T) {
 		conf = config.NewConfig()
 		cmd.SetOut(output)
 		cmd.SetArgs([]string{
+			"--configFile", filepath.Join(testDir, "testdata", "config.yml"),
 			"start",
 			"--provider.name", "cli",
 			"--server.port", "3333",