Change environment prefix from nms to nginx_agent (#706)

* changed env variable prefix from NMS to NGINX_AGENT

* changed env variable prefix from NMS to NGINX_AGENT

* renamed env prefix constants

* renamed env prefix constants

* refactored string building of oldKey and newKey

* refactored string building of oldKey and newKey

* added test for env prefix migration

* added test for env prefix migration

* refactored string builing of oldKey and newKey

* refactored string builing of oldKey and newKey

* fixed deprecated env prefix migration test

main.go

@@ -59,6 +59,10 @@ func main() {
 			defer logFile.Close()
 		}
 
+		if config.MigratedEnv {
+			log.Warnf("The environment variable prefix 'NMS' is deprecated. Prefix has been migrated to 'NGINX_AGENT'. Please update your configuration to use the new prefix.")
+		}
+
 		log.Tracef("Config loaded from disk, %v", loadedConfig)
 
 		if loadedConfig.DisplayName == "" {

src/core/config/config.go

@@ -47,7 +47,10 @@ const (
 `
 )
 
-var Viper = viper.NewWithOptions(viper.KeyDelimiter(agent_config.KeyDelimiter))
+var (
+	Viper       = viper.NewWithOptions(viper.KeyDelimiter(agent_config.KeyDelimiter))
+	MigratedEnv = false
+)
 
 func SetVersion(version, commit string) {
 	ROOT_COMMAND.Version = version + "-" + commit
@@ -149,6 +152,17 @@ func RegisterFlags() {
 		if err := Viper.BindPFlag(strings.ReplaceAll(flag.Name, "-", "_"), fs.Lookup(flag.Name)); err != nil {
 			return
 		}
+
+		oldKey := strings.ToUpper(LegacyEnvPrefix + agent_config.KeyDelimiter + strings.ReplaceAll(flag.Name, "-", agent_config.KeyDelimiter))
+		newKey := strings.ToUpper(EnvPrefix + agent_config.KeyDelimiter + strings.ReplaceAll(flag.Name, "-", agent_config.KeyDelimiter))
+
+		if os.Getenv(oldKey) != "" && os.Getenv(newKey) == "" {
+			if err := os.Setenv(newKey, os.Getenv(oldKey)); err != nil {
+				log.Warnf("Failed to set environment variable %s: %v", newKey, err)
+			}
+			MigratedEnv = true
+		}
+
 		err := Viper.BindEnv(flag.Name)
 		if err != nil {
 			log.Warnf("Error occurred binding env %s: %v", flag.Name, err)

src/core/config/config_test.go

@@ -479,6 +479,36 @@ func TestUpdateAgentConfig(t *testing.T) {
 	}
 }
 
+func TestDeprecatedEnvPrefixMigration(t *testing.T) {
+	want := true
+
+	curDir, err := os.Getwd()
+	require.NoError(t, err)
+
+	tempConfDeleteFunc, err := sysutils.CopyFile(fmt.Sprintf("%s/%s", testCfgDir, emptyConfigFile), tempCfgFile)
+	defer func() {
+		err := tempConfDeleteFunc()
+		require.NoError(t, err, "deletion of temp config file failed")
+	}()
+	require.NoError(t, err)
+
+	tempDynamicDeleteFunc, err := sysutils.CopyFile(fmt.Sprintf("%s/%s", testCfgDir, emptyConfigFile), tempDynamicCfgFile)
+	defer func() {
+		err := tempDynamicDeleteFunc()
+		require.NoError(t, err, "deletion of temp dynamic config file failed")
+	}()
+	require.NoError(t, err)
+
+	cleanEnv(t, tempCfgFile, fmt.Sprintf("%s/%s", curDir, tempDynamicCfgFile))
+	setEnvVariable(t, "tls_skip_verify", "true")
+
+	config, err := GetConfig("1234")
+	require.NoError(t, err)
+
+	got := config.TLS.SkipVerify
+	assert.Equal(t, want, got)
+}
+
 func setEnvVariable(t *testing.T, name string, value string) {
 	key := strings.ToUpper(EnvPrefix + agent_config.KeyDelimiter + name)
 	err := os.Setenv(key, value)

src/core/config/defaults.go

@@ -103,7 +103,8 @@ const (
 	DynamicConfigFileAbsFreeBsdPath = "/var/db/nginx-agent/agent-dynamic.conf"
 	ConfigFileName                  = "nginx-agent.conf"
 	ConfigFileType                  = "yaml"
-	EnvPrefix                       = "nms"
+	LegacyEnvPrefix                 = "nms"
+	EnvPrefix                       = "nginx_agent"
 	ConfigPathKey                   = "path"
 	DynamicConfigPathKey            = "dynamic_config_path"