feat: add config:clear command

Closes #3537

docs/configuration/environment-variables.md

@@ -6,12 +6,13 @@ The `config` plugin provides the following commands to manage your variables:
 
 ```
 config (<app>|--global)                                                               Pretty-print an app or global environment
+config:bundle (<app>|--global) [--merged]                                             Bundle environment into tarfile
+config:clear (<app>|--global)                                                         Clears environment variables
+config:export (<app>|--global) [--envfile]                                            Export a global or app environment
 config:get (<app>|--global) KEY                                                       Display a global or app-specific config value
+config:keys (<app>|--global) [--merged]                                               Show keys set in environment
 config:set [--encoded] [--no-restart] (<app>|--global) KEY1=VALUE1 [KEY2=VALUE2 ...]  Set one or more config vars
 config:unset [--no-restart] (<app>|--global) KEY1 [KEY2 ...]                          Unset one or more config vars
-config:export (<app>|--global) [--envfile]                                            Export a global or app environment
-config:keys (<app>|--global) [--merged]                                               Show keys set in environment
-config:bundle (<app>|--global) [--merged]                                             Bundle environment into tarfile
 ```
 > For security reasons - and as per [docker recommendations](https://github.com/docker/docker/issues/13490) - Dockerfile-based deploys have variables available *only* during runtime, as noted in [this issue](https://github.com/dokku/dokku/issues/1860).
 

plugins/config/config.go

@@ -92,6 +92,29 @@ func UnsetMany(appName string, keys []string, restart bool) (err error) {
 	return
 }
 
+//UnsetAll removes all config keys
+func UnsetAll(appName string, restart bool) (err error) {
+	global := appName == ""
+	env, err := loadAppOrGlobalEnv(appName)
+	if err != nil {
+		return
+	}
+	var changed = false
+	for k := range env.Map() {
+		common.LogInfo1Quiet(fmt.Sprintf("Unsetting %s", k))
+		env.Unset(k)
+		changed = true
+	}
+	if changed {
+		env.Write()
+		triggerUpdate(appName, "clear", []string{})
+	}
+	if !global && restart && env.GetBoolDefault("DOKKU_APP_RESTORE", true) {
+		triggerRestart(appName)
+	}
+	return
+}
+
 func triggerRestart(appName string) {
 	common.LogInfo1(fmt.Sprintf("Restarting app %s", appName))
 	if err := common.PlugnTrigger("app-restart", appName); err != nil {

plugins/config/config_test.go

@@ -80,6 +80,22 @@ func TestConfigSetMany(t *testing.T) {
 	Expect(SetMany(testAppName+"does_not_exist", vals, false)).ToNot(Succeed())
 }
 
+func TestConfigUnsetAll(t *testing.T) {
+	RegisterTestingT(t)
+	Expect(setupTestApp()).To(Succeed())
+	defer teardownTestApp()
+
+	expectValue(testAppName, "testKey", "TESTING")
+	expectValue("", "testKey", "GLOBAL_TESTING")
+
+	Expect(UnsetAll(testAppName, false)).To(Succeed())
+	expectNoValue(testAppName, "testKey")
+	expectNoValue(testAppName, "noKey")
+	expectNoValue(testAppName, "globalKey")
+
+	Expect(UnsetAll(testAppName+"does-not-exist", false)).ToNot(Succeed())
+}
+
 func TestConfigUnsetMany(t *testing.T) {
 	RegisterTestingT(t)
 	Expect(setupTestApp()).To(Succeed())

plugins/config/functions

@@ -46,6 +46,11 @@ config_get() {
   config_sub get "$@"
 }
 
+config_clear() {
+  declare desc="clears config vars"
+  config_sub clear "$@"
+}
+
 config_set() {
   declare desc="set value of given config var"
   config_sub set "$@"

plugins/config/src/commands/commands.go

@@ -22,6 +22,7 @@ Additional commands:`
 	helpContent = `
     config (<app>|--global), Pretty-print an app or global environment
     config:bundle (<app>|--global) [--merged], Bundle environment into tarfile
+    config:clear (<app>|--global), Clears environment variables
     config:export (<app>|--global) [--envfile], Export a global or app environment
     config:get (<app>|--global) KEY, Display a global or app-specific config value
     config:keys (<app>|--global) [--merged], Show keys set in environment

plugins/config/src/subcommands/clear/clear.go

@@ -0,0 +1,17 @@
+package main
+
+import (
+	"flag"
+	"os"
+
+	"github.com/dokku/dokku/plugins/config"
+)
+
+//clear all entries from the given environment
+func main() {
+	args := flag.NewFlagSet("config:clear", flag.ExitOnError)
+	global := args.Bool("global", false, "--global: use the global environment")
+	noRestart := args.Bool("no-restart", false, "--no-restart: no restart")
+	args.Parse(os.Args[2:])
+	config.CommandClear(args.Args(), *global, *noRestart)
+}

plugins/config/subcommands.go

@@ -50,6 +50,15 @@ func CommandGet(args []string, global bool, quoted bool) {
 	}
 }
 
+//CommandClear implements config:clear
+func CommandClear(args []string, global bool, noRestart bool) {
+	appName, _ := getCommonArgs(global, args)
+	err := UnsetAll(appName, !noRestart)
+	if err != nil {
+		common.LogFail(err.Error())
+	}
+}
+
 //CommandUnset implements config:unset
 func CommandUnset(args []string, global bool, noRestart bool) {
 	appName, keys := getCommonArgs(global, args)