Merge pull request #7983 from mattfarina/xdg

Adding Helm env vars where XDG exposed

cmd/helm/root.go

@@ -45,19 +45,19 @@ Environment variables:
 
 | Name                               | Description                                                                       |
 |------------------------------------|-----------------------------------------------------------------------------------|
-| $XDG_CACHE_HOME                    | set an alternative location for storing cached files.                             |
-| $XDG_CONFIG_HOME                   | set an alternative location for storing Helm configuration.                       |
-| $XDG_DATA_HOME                     | set an alternative location for storing Helm data.                                |
+| $HELM_CACHE_HOME                   | set an alternative location for storing cached files.                             |
+| $HELM_CONFIG_HOME                  | set an alternative location for storing Helm configuration.                       |
+| $HELM_DATA_HOME                    | set an alternative location for storing Helm data.                                |
 | $HELM_DRIVER                       | set the backend storage driver. Values are: configmap, secret, memory, postgres   |
 | $HELM_DRIVER_SQL_CONNECTION_STRING | set the connection string the SQL storage driver should use.                      |
 | $HELM_NO_PLUGINS                   | disable plugins. Set HELM_NO_PLUGINS=1 to disable plugins.                        |
 | $KUBECONFIG                        | set an alternative Kubernetes configuration file (default "~/.kube/config")       |
 
-Helm stores configuration based on the XDG base directory specification, so
+Helm stores cache, configuration, and data based on the following configuration order:
 
-- cached files are stored in $XDG_CACHE_HOME/helm
-- configuration is stored in $XDG_CONFIG_HOME/helm
-- data is stored in $XDG_DATA_HOME/helm
+- If a HELM_*_HOME environment variable is set, it will be used
+- Otherwise, on systems supporting the XDG base directory specification, the XDG variables will be used
+- When no other location is set a default location will be used based on the operating system
 
 By default, the default directories depend on the Operating System. The defaults are listed below:
 

cmd/helm/root_test.go

@@ -55,6 +55,24 @@ func TestRootCmd(t *testing.T) {
 			envvars:  map[string]string{xdg.DataHomeEnvVar: "/bar"},
 			dataPath: "/bar/helm",
 		},
+		{
+			name:      "with $HELM_CACHE_HOME set",
+			args:      "env",
+			envvars:   map[string]string{helmpath.CacheHomeEnvVar: "/foo/helm"},
+			cachePath: "/foo/helm",
+		},
+		{
+			name:       "with $HELM_CONFIG_HOME set",
+			args:       "env",
+			envvars:    map[string]string{helmpath.ConfigHomeEnvVar: "/foo/helm"},
+			configPath: "/foo/helm",
+		},
+		{
+			name:     "with $HELM_DATA_HOME set",
+			args:     "env",
+			envvars:  map[string]string{helmpath.DataHomeEnvVar: "/foo/helm"},
+			dataPath: "/foo/helm",
+		},
 	}
 
 	for _, tt := range tests {

internal/test/ensure/ensure.go

@@ -21,6 +21,7 @@ import (
 	"os"
 	"testing"
 
+	"helm.sh/helm/v3/pkg/helmpath"
 	"helm.sh/helm/v3/pkg/helmpath/xdg"
 )
 
@@ -31,6 +32,9 @@ func HelmHome(t *testing.T) func() {
 	os.Setenv(xdg.CacheHomeEnvVar, base)
 	os.Setenv(xdg.ConfigHomeEnvVar, base)
 	os.Setenv(xdg.DataHomeEnvVar, base)
+	os.Setenv(helmpath.CacheHomeEnvVar, "")
+	os.Setenv(helmpath.ConfigHomeEnvVar, "")
+	os.Setenv(helmpath.DataHomeEnvVar, "")
 	return func() {
 		os.RemoveAll(base)
 	}

pkg/cli/environment.go

@@ -105,6 +105,9 @@ func envOr(name, def string) string {
 func (s *EnvSettings) EnvVars() map[string]string {
 	envvars := map[string]string{
 		"HELM_BIN":               os.Args[0],
+		"HELM_CACHE_HOME":        helmpath.CachePath(""),
+		"HELM_CONFIG_HOME":       helmpath.ConfigPath(""),
+		"HELM_DATA_HOME":         helmpath.DataPath(""),
 		"HELM_DEBUG":             fmt.Sprint(s.Debug),
 		"HELM_PLUGINS":           s.PluginsDirectory,
 		"HELM_REGISTRY_CONFIG":   s.RegistryConfig,

pkg/helmpath/lazypath.go

@@ -20,11 +20,34 @@ import (
 	"helm.sh/helm/v3/pkg/helmpath/xdg"
 )
 
+const (
+	// CacheHomeEnvVar is the environment variable used by Helm
+	// for the cache directory. When no value is set a default is used.
+	CacheHomeEnvVar = "HELM_CACHE_HOME"
+
+	// ConfigHomeEnvVar is the environment variable used by Helm
+	// for the config directory. When no value is set a default is used.
+	ConfigHomeEnvVar = "HELM_CONFIG_HOME"
+
+	// DataHomeEnvVar is the environment variable used by Helm
+	// for the data directory. When no value is set a default is used.
+	DataHomeEnvVar = "HELM_DATA_HOME"
+)
+
 // lazypath is an lazy-loaded path buffer for the XDG base directory specification.
 type lazypath string
 
-func (l lazypath) path(envVar string, defaultFn func() string, elem ...string) string {
-	base := os.Getenv(envVar)
+func (l lazypath) path(helmEnvVar, xdgEnvVar string, defaultFn func() string, elem ...string) string {
+
+	// There is an order to checking for a path.
+	// 1. See if a Helm specific environment variable has been set.
+	// 2. Check if an XDG environment variable is set
+	// 3. Fall back to a default
+	base := os.Getenv(helmEnvVar)
+	if base != "" {
+		return filepath.Join(base, filepath.Join(elem...))
+	}
+	base = os.Getenv(xdgEnvVar)
 	if base == "" {
 		base = defaultFn()
 	}
@@ -34,16 +57,16 @@ func (l lazypath) path(envVar string, defaultFn func() string, elem ...string) s
 // cachePath defines the base directory relative to which user specific non-essential data files
 // should be stored.
 func (l lazypath) cachePath(elem ...string) string {
-	return l.path(xdg.CacheHomeEnvVar, cacheHome, filepath.Join(elem...))
+	return l.path(CacheHomeEnvVar, xdg.CacheHomeEnvVar, cacheHome, filepath.Join(elem...))
 }
 
 // configPath defines the base directory relative to which user specific configuration files should
 // be stored.
 func (l lazypath) configPath(elem ...string) string {
-	return l.path(xdg.ConfigHomeEnvVar, configHome, filepath.Join(elem...))
+	return l.path(ConfigHomeEnvVar, xdg.ConfigHomeEnvVar, configHome, filepath.Join(elem...))
 }
 
 // dataPath defines the base directory relative to which user specific data files should be stored.
 func (l lazypath) dataPath(elem ...string) string {
-	return l.path(xdg.DataHomeEnvVar, dataHome, filepath.Join(elem...))
+	return l.path(DataHomeEnvVar, xdg.DataHomeEnvVar, dataHome, filepath.Join(elem...))
 }