[v9.5.x] Auth: id response header (#78879)

Auth: id response header (#77871)

* Add config options for identity id response header

* Add feature to add identity id response header to all responses

* Use util.SplitString

(cherry picked from commit 21f94c5b78)

pkg/setting/setting.go

@@ -270,6 +270,9 @@ type Cfg struct {
 	AdminEmail                   string
 	DisableSyncLock              bool
 	DisableLoginForm             bool
+	IDResponseHeaderEnabled      bool
+	IDResponseHeaderPrefix       string
+	IDResponseHeaderNamespaces   map[string]struct{}
 
 	// AWS Plugin Auth
 	AWSAllowedAuthProviders []string
@@ -1491,6 +1494,17 @@ func readAuthSettings(iniFile *ini.File, cfg *Cfg) (err error) {
 	// Azure Auth
 	AzureAuthEnabled = auth.Key("azure_auth_enabled").MustBool(false)
 	cfg.AzureAuthEnabled = AzureAuthEnabled
+
+	// ID response header
+	cfg.IDResponseHeaderEnabled = auth.Key("id_response_header_enabled").MustBool(false)
+	cfg.IDResponseHeaderPrefix = auth.Key("id_response_header_prefix").MustString("X-Grafana-")
+
+	idHeaderNamespaces := util.SplitString(auth.Key("id_response_header_namespaces").MustString(""))
+	cfg.IDResponseHeaderNamespaces = make(map[string]struct{}, len(idHeaderNamespaces))
+	for _, namespace := range idHeaderNamespaces {
+		cfg.IDResponseHeaderNamespaces[namespace] = struct{}{}
+	}
+
 	readAuthAzureADSettings(cfg)
 
 	// Google Auth