Implement v4 endpoints for OAuth (#6040)

* Implement POST /oauth/apps endpoint for APIv4

* Implement GET /oauth/apps endpoint for APIv4

* Implement GET /oauth/apps/{app_id} and /oauth/apps/{app_id}/info endpoints for APIv4

* Refactor API version independent oauth endpoints

* Implement DELETE /oauth/apps/{app_id} endpoint for APIv4

* Implement /oauth/apps/{app_id}/regen_secret endpoint for APIv4

* Implement GET /user/{user_id}/oauth/apps/authorized endpoint for APIv4

* Implement POST /oauth/deauthorize endpoint

api4/api.go

@@ -64,8 +64,10 @@ type Routes struct {
 	OutgoingHooks *mux.Router // 'api/v4/hooks/outgoing'
 	OutgoingHook  *mux.Router // 'api/v4/hooks/outgoing/{hook_id:[A-Za-z0-9]+}'
 
-	Admin      *mux.Router // 'api/v4/admin'
-	OAuth      *mux.Router // 'api/v4/oauth'
+	OAuth     *mux.Router // 'api/v4/oauth'
+	OAuthApps *mux.Router // 'api/v4/oauth/apps'
+	OAuthApp  *mux.Router // 'api/v4/oauth/apps/{app_id:[A-Za-z0-9]+}'
+
 	SAML       *mux.Router // 'api/v4/saml'
 	Compliance *mux.Router // 'api/v4/compliance'
 	Cluster    *mux.Router // 'api/v4/cluster'
@@ -146,8 +148,11 @@ func InitApi(full bool) {
 	BaseRoutes.OutgoingHook = BaseRoutes.OutgoingHooks.PathPrefix("/{hook_id:[A-Za-z0-9]+}").Subrouter()
 
 	BaseRoutes.SAML = BaseRoutes.ApiRoot.PathPrefix("/saml").Subrouter()
+
 	BaseRoutes.OAuth = BaseRoutes.ApiRoot.PathPrefix("/oauth").Subrouter()
-	BaseRoutes.Admin = BaseRoutes.ApiRoot.PathPrefix("/admin").Subrouter()
+	BaseRoutes.OAuthApps = BaseRoutes.OAuth.PathPrefix("/apps").Subrouter()
+	BaseRoutes.OAuthApp = BaseRoutes.OAuthApps.PathPrefix("/{app_id:[A-Za-z0-9]+}").Subrouter()
+
 	BaseRoutes.Compliance = BaseRoutes.ApiRoot.PathPrefix("/compliance").Subrouter()
 	BaseRoutes.Cluster = BaseRoutes.ApiRoot.PathPrefix("/cluster").Subrouter()
 	BaseRoutes.LDAP = BaseRoutes.ApiRoot.PathPrefix("/ldap").Subrouter()
@@ -180,6 +185,7 @@ func InitApi(full bool) {
 	InitStatus()
 	InitWebSocket()
 	InitEmoji()
+	InitOAuth()
 	InitReaction()
 	InitWebrtc()