resolve wildcards in DB resource name (#100)

Author: laurenzlong

spec/providers/database.spec.ts

@@ -63,6 +63,23 @@ describe('DatabaseBuilder', () => {
         },
       } as any);
     });
+
+    it('should interpolate params until the server does it', () => {
+      let handler = database.ref('/users/{id}').onWrite(event => {
+        expect(event.resource).to.equal('projects/_/instances/subdomain/refs/users/aUserId');
+      });
+
+      return handler({
+        data: {
+          data: null,
+          delta: 'hello',
+        },
+        resource: 'projects/_/instances/subdomains/refs/users/{id}',
+        params: {
+          id: 'aUserId',
+        },
+      });
+    });
   });
 });
 

src/providers/database.ts

@@ -105,6 +105,9 @@ export class DeltaSnapshot implements firebase.database.DataSnapshot {
   constructor(private app: firebase.app.App, private adminApp: firebase.app.App, event: Event<any>) {
     if (event) {
       let resourceRegex = `projects/([^/]+)/instances/([^/]+)/refs(/.+)?`;
+      _.forEach(event.params, (val, key) => {
+        event.resource = _.replace(event.resource, `{${key}}`, val);
+      });
       let match = event.resource.match(new RegExp(resourceRegex));
       if (!match) {
         throw new Error(`Unexpected resource string for Firebase Realtime Database event: ${event.resource}. ` +