fix(hosting): route Cloud Run rewrites to local functions emulator

CHANGELOG.md

@@ -1,3 +1,4 @@
+- Fixed an issue where Cloud Run rewrites in the Hosting emulator would always hit the live Cloud Run API instead of routing to the local functions emulator. (#10588)
 - Updated the Firebase Data Connect local toolkit to v3.4.11, which includes the following changes:
   - [changed] Updated the Golang dependency version to 1.25.11.
 - Fixed issue where `apptesting:execute` command rejects documented `--test-username`, `--test-password`, and `--test-password-file` options.

src/hosting/cloudRunProxy.spec.ts

@@ -6,16 +6,21 @@
 
 import { cloudRunApiOrigin } from "../api";
 import cloudRunProxy, { CloudRunProxyOptions, CloudRunProxyRewrite } from "./cloudRunProxy";
+import { EmulatorRegistry } from "../emulator/registry";
+import { Emulators } from "../emulator/types";
+import { FakeEmulator } from "../emulator/testing/fakeEmulator";
 
 describe("cloudRunProxy", () => {
   const fakeOptions: CloudRunProxyOptions = {
     project: "project-foo",
+    targets: [],
   };
   const fakeRewrite: CloudRunProxyRewrite = { run: { serviceId: "helloworld" } };
   const cloudRunServiceOrigin = "https://helloworld-hash-uc.a.run.app";
 
-  afterEach(() => {
+  afterEach(async () => {
     nock.cleanAll();
+    await EmulatorRegistry.stopAll();
   });
 
   it("should error when not provided a valid Cloud Run service ID", async () => {
@@ -216,7 +221,7 @@
     const mw = await mwGenerator(fakeRewrite);
     const spyMw = sinon.spy(mw);
     const finalMw = sinon.stub().callsFake((_, res) => {
       res.status(404).send("unknown response");
     });
 
     const app = express();
@@ -248,7 +253,7 @@
       .expect(200, "cached page")
       .then((res) => {
         expect(spyMw.calledOnce).to.be.true;
         expect(res.header["set-cookie"]).to.be.undefined;
       });
   });
 
@@ -269,7 +274,7 @@
       .expect(200, "live vary version")
       .then((res) => {
         expect(spyMw.calledOnce).to.be.true;
         expect(res.header.vary).to.equal("Other, Authorization, Accept-Encoding, Cookie");
       });
   });
 
@@ -330,4 +335,52 @@
         expect(spyMw.calledOnce).to.be.true;
       });
   });
+
+  it("should route to the local functions emulator when targets includes 'functions'", async () => {
+    const fakeFunctionsEmulator = new FakeEmulator(Emulators.FUNCTIONS, [
+      { address: "127.0.0.1", family: "IPv4", port: 7778 },
+    ]);
+    await EmulatorRegistry.start(fakeFunctionsEmulator);
+
+    nock("http://127.0.0.1:7778")
+      .get("/project-foo/us-central1/helloworld/")
+      .reply(200, "local version");
+
+    const options: CloudRunProxyOptions = { ...fakeOptions, targets: ["functions"] };
+
+    const mwGenerator = cloudRunProxy(options);
+    const mw = await mwGenerator(fakeRewrite);
+    const spyMw = sinon.spy(mw);
+
+    return supertest(spyMw)
+      .get("/")
+      .expect(200, "local version")
+      .then(() => {
+        expect(spyMw.calledOnce).to.be.true;
+      });
+  });
+
+  it("should route to the local functions emulator in another region", async () => {
+    const fakeFunctionsEmulator = new FakeEmulator(Emulators.FUNCTIONS, [
+      { address: "127.0.0.1", family: "IPv4", port: 7778 },
+    ]);
+    await EmulatorRegistry.start(fakeFunctionsEmulator);
+
+    nock("http://127.0.0.1:7778")
+      .get("/project-foo/asia-southeast1/helloworld/")
+      .reply(200, "local version");
+
+    const options: CloudRunProxyOptions = { ...fakeOptions, targets: ["functions"] };
+
+    const mwGenerator = cloudRunProxy(options);
+    const mw = await mwGenerator({ run: { serviceId: "helloworld", region: "asia-southeast1" } });
+    const spyMw = sinon.spy(mw);
+
+    return supertest(spyMw)
+      .get("/")
+      .expect(200, "local version")
+      .then(() => {
+        expect(spyMw.calledOnce).to.be.true;
+      });
+  });
 });

src/hosting/cloudRunProxy.ts

@@ -6,9 +6,13 @@
 import { FirebaseError } from "../error";
 import { logger } from "../logger";
 import { needProjectId } from "../projectUtils";
+import { EmulatorRegistry } from "../emulator/registry";
+import { Emulators } from "../emulator/types";
+import { FunctionsEmulator } from "../emulator/functionsEmulator";
 
 export interface CloudRunProxyOptions {
   project?: string;
+  targets?: string[];
 }
 
 export interface CloudRunProxyRewrite {
@@ -23,7 +27,7 @@
 const apiClient = new Client({ urlPrefix: cloudRunApiOrigin(), apiVersion: "v1" });
 
 async function getCloudRunUrl(rewrite: CloudRunProxyRewrite, projectId: string): Promise<string> {
   const alreadyFetched = cloudRunCache[`${rewrite.run.region}/${rewrite.run.serviceId}`];
   if (alreadyFetched) {
     return Promise.resolve(alreadyFetched);
   }
@@ -39,10 +43,10 @@
       throw new FirebaseError("Cloud Run URL doesn't exist in response.");
     }
 
     cloudRunCache[`${rewrite.run.region}/${rewrite.run.serviceId}`] = url;
     return url;
   } catch (err: any) {
     throw new FirebaseError(`Error looking up URL for Cloud Run service: ${err}`, {
       original: err,
     });
   }
@@ -70,6 +74,17 @@
     logger.info(`[hosting] Cloud Run rewrite ${JSON.stringify(rewrite)} triggered`);
 
     const textIdentifier = `Cloud Run service "${rewrite.run.serviceId}" for region "${rewrite.run.region}"`;
+
+    if (options.targets?.includes("functions") && EmulatorRegistry.isRunning(Emulators.FUNCTIONS)) {
+      const projectId = needProjectId(options);
+      const url = FunctionsEmulator.getHttpFunctionUrl(
+        projectId,
+        rewrite.run.serviceId,
+        rewrite.run.region,
+      );
+      return proxyRequestHandler(url, `local ${textIdentifier}`);
+    }
+
     return getCloudRunUrl(rewrite, needProjectId(options))
       .then((url) => proxyRequestHandler(url, textIdentifier))
       .catch(errorRequestHandler);