Use domain in context to override RTDB domain #683 (#235)

Author: fredzqm

spec/providers/database.spec.ts

@@ -32,7 +32,7 @@ describe('Database Functions', () => {
 
     before(() => {
       process.env.FIREBASE_CONFIG = JSON.stringify({
-        databaseURL: 'https://subdomain.firebaseio.com',
+        databaseURL: 'https://subdomain.apse.firebasedatabase.app',
       });
       appsNamespace.init();
     });
@@ -424,29 +424,51 @@ describe('Database Functions', () => {
     });
   });
 
-  describe('resourceToInstanceAndPath', () => {
-    it('should return the correct instance and path strings', () => {
-      const [instance, path] = database.resourceToInstanceAndPath(
-        'projects/_/instances/foo/refs/bar'
+  describe('extractInstanceAndPath', () => {
+    it('should return correct us-central prod instance and path strings if domain is missing', () => {
+      const [instance, path] = database.extractInstanceAndPath(
+        'projects/_/instances/foo/refs/bar',
+        undefined
       );
       expect(instance).to.equal('https://foo.firebaseio.com');
       expect(path).to.equal('/bar');
     });
 
+    it('should return the correct staging instance and path strings if domain is present', () => {
+      const [instance, path] = database.extractInstanceAndPath(
+        'projects/_/instances/foo/refs/bar',
+        'firebaseio-staging.com'
+      );
+      expect(instance).to.equal('https://foo.firebaseio-staging.com');
+      expect(path).to.equal('/bar');
+    });
+
+    it('should return the correct multi-region instance and path strings if domain is present', () => {
+      const [instance, path] = database.extractInstanceAndPath(
+        'projects/_/instances/foo/refs/bar',
+        'euw1.firebasedatabase.app'
+      );
+      expect(instance).to.equal('https://foo.euw1.firebasedatabase.app');
+      expect(path).to.equal('/bar');
+    });
+
     it('should throw an error if the given instance name contains anything except alphanumerics and dashes', () => {
       expect(() => {
-        return database.resourceToInstanceAndPath(
-          'projects/_/instances/a.bad.name/refs/bar'
+        return database.extractInstanceAndPath(
+          'projects/_/instances/a.bad.name/refs/bar',
+          undefined
         );
       }).to.throw(Error);
       expect(() => {
-        return database.resourceToInstanceAndPath(
-          'projects/_/instances/a_different_bad_name/refs/bar'
+        return database.extractInstanceAndPath(
+          'projects/_/instances/a_different_bad_name/refs/bar',
+          undefined
         );
       }).to.throw(Error);
       expect(() => {
-        return database.resourceToInstanceAndPath(
-          'projects/_/instances/BAD!!!!/refs/bar'
+        return database.extractInstanceAndPath(
+          'projects/_/instances/BAD!!!!/refs/bar',
+          undefined
         );
       }).to.throw(Error);
     });
@@ -457,8 +479,9 @@ describe('Database Functions', () => {
     const apps = new appsNamespace.Apps();
 
     const populate = (data: any) => {
-      const [instance, path] = database.resourceToInstanceAndPath(
-        'projects/_/instances/other-subdomain/refs/foo'
+      const [instance, path] = database.extractInstanceAndPath(
+        'projects/_/instances/other-subdomain/refs/foo',
+        'firebaseio-staging.com'
       );
       subject = new database.DataSnapshot(data, path, apps.admin, instance);
     };
@@ -467,7 +490,7 @@ describe('Database Functions', () => {
       it('should return a ref for correct instance, not the default instance', () => {
         populate({});
         expect(subject.ref.toJSON()).to.equal(
-          'https://other-subdomain.firebaseio.com/foo'
+          'https://other-subdomain.firebaseio-staging.com/foo'
         );
       });
     });
@@ -648,8 +671,9 @@ describe('Database Functions', () => {
       });
 
       it('should return null for the root', () => {
-        const [instance, path] = database.resourceToInstanceAndPath(
-          'projects/_/instances/foo/refs/'
+        const [instance, path] = database.extractInstanceAndPath(
+          'projects/_/instances/foo/refs/',
+          undefined
         );
         const snapshot = new database.DataSnapshot(
           null,

src/cloud-functions.ts

@@ -39,6 +39,7 @@ export interface Event {
     timestamp: string;
     eventType: string;
     resource: Resource;
+    domain?: string;
   };
   data: any;
 }

src/providers/database.ts

@@ -40,8 +40,7 @@ export const provider = 'google.firebase.database';
 /** @hidden */
 export const service = 'firebaseio.com';
 
-// NOTE(inlined): Should we relax this a bit to allow staging or alternate implementations of our API?
-const databaseURLRegex = new RegExp('https://([^.]+).firebaseio.com');
+const databaseURLRegex = new RegExp('^https://([^.]+).');
 
 /**
  * Registers a function that triggers on events from a specific
@@ -215,8 +214,9 @@ export class RefBuilder {
     ) => PromiseLike<any> | any
   ): CloudFunction<DataSnapshot> {
     const dataConstructor = (raw: Event) => {
-      const [dbInstance, path] = resourceToInstanceAndPath(
-        raw.context.resource.name
+      const [dbInstance, path] = extractInstanceAndPath(
+        raw.context.resource.name,
+        raw.context.domain
       );
       return new DataSnapshot(
         raw.data.delta,
@@ -243,8 +243,9 @@ export class RefBuilder {
     ) => PromiseLike<any> | any
   ): CloudFunction<DataSnapshot> {
     const dataConstructor = (raw: Event) => {
-      const [dbInstance, path] = resourceToInstanceAndPath(
-        raw.context.resource.name
+      const [dbInstance, path] = extractInstanceAndPath(
+        raw.context.resource.name,
+        raw.context.domain
       );
       return new DataSnapshot(raw.data.data, path, this.apps.admin, dbInstance);
     };
@@ -271,8 +272,9 @@ export class RefBuilder {
   }
 
   private changeConstructor = (raw: Event): Change<DataSnapshot> => {
-    const [dbInstance, path] = resourceToInstanceAndPath(
-      raw.context.resource.name
+    const [dbInstance, path] = extractInstanceAndPath(
+      raw.context.resource.name,
+      raw.context.domain
     );
     const before = new DataSnapshot(
       raw.data.data,
@@ -293,9 +295,19 @@ export class RefBuilder {
   };
 }
 
-/* Utility function to extract database reference from resource string */
+/**
+ * Utility function to extract database reference from resource string
+ *
+ * @param optional database domain override for the original of the source database.
+ *    It defaults to `firebaseio.com`.
+ *    Multi-region RTDB will be served from different domains.
+ *    Since region is not part of the resource name, it is provided through context.
+ */
 /** @hidden */
-export function resourceToInstanceAndPath(resource: string) {
+export function extractInstanceAndPath(
+  resource: string,
+  domain = 'firebaseio.com'
+) {
   const resourceRegex = `projects/([^/]+)/instances/([a-zA-Z0-9\-^/]+)/refs(/.+)?`;
   const match = resource.match(new RegExp(resourceRegex));
   if (!match) {
@@ -310,7 +322,7 @@ export function resourceToInstanceAndPath(resource: string) {
       `Expect project to be '_' in a Firebase Realtime Database event`
     );
   }
-  const dbInstance = 'https://' + dbInstanceName + '.firebaseio.com';
+  const dbInstance = 'https://' + dbInstanceName + '.' + domain;
   return [dbInstance, path];
 }