Add initial delay when loading python functions

CHANGELOG.md

@@ -1 +1,2 @@
+- Add initial delay when loading python functions (#8239)
 - Enforce webframeworks enablement only on webframeworks sites (#8168)

src/deploy/functions/runtimes/discovery/index.spec.ts

@@ -101,9 +101,22 @@ describe("detectFromPort", () => {
       code: "ECONNREFUSED",
     });
 
+    nock("http://127.0.0.1:8080").get("/__/functions.yaml").times(3).replyWithError({
+      message: "Almost there",
+      code: "ETIMEDOUT",
+    });
+
     nock("http://127.0.0.1:8080").get("/__/functions.yaml").reply(200, YAML_TEXT);
 
     const parsed = await discovery.detectFromPort(8080, "project", "nodejs16");
     expect(parsed).to.deep.equal(BUILD);
   });
+
+  it("retries when request times out", async () => {
+    nock("http://127.0.0.1:8081").get("/__/functions.yaml").delay(1_000).reply(200, YAML_TEXT);
+    nock("http://127.0.0.1:8080").get("/__/functions.yaml").reply(200, YAML_TEXT);
+
+    const parsed = await discovery.detectFromPort(8080, "project", "nodejs16", 0, 500);
+    expect(parsed).to.deep.equal(BUILD);
+  });
 });

src/deploy/functions/runtimes/discovery/index.ts

@@ -15,7 +15,7 @@
 
 const TIMEOUT_OVERRIDE_ENV_VAR = "FUNCTIONS_DISCOVERY_TIMEOUT";
 
 export function getFunctionDiscoveryTimeout(): number {
   return +(process.env[TIMEOUT_OVERRIDE_ENV_VAR] || 0) * 1000; /* ms */
 }
 
@@ -23,22 +23,22 @@
  * Converts the YAML retrieved from discovery into a Build object for param interpolation.
  */
 export function yamlToBuild(
   yaml: any,
   project: string,
   region: string,
   runtime: Runtime,
 ): build.Build {
   try {
     if (!yaml.specVersion) {
       throw new FirebaseError("Expect manifest yaml to specify a version number");
     }
     if (yaml.specVersion === "v1alpha1") {
       return v1alpha1.buildFromV1Alpha1(yaml, project, region, runtime);
     }
     throw new FirebaseError(
       "It seems you are using a newer SDK than this version of the CLI can handle. Please update your CLI with `npm install -g firebase-tools`",
     );
   } catch (err: any) {
     throw new FirebaseError("Failed to parse build specification", { children: [err] });
   }
 }
@@ -53,9 +53,9 @@
 ): Promise<build.Build | undefined> {
   let text: string;
   try {
     text = await exports.readFileAsync(path.join(directory, "functions.yaml"), "utf8");
   } catch (err: any) {
     if (err.code === "ENOENT") {
       logger.debug("Could not find functions.yaml. Must use http discovery");
     } else {
       logger.debug("Unexpected error looking for functions.yaml file:", err);
@@ -75,6 +75,7 @@
   port: number,
   project: string,
   runtime: Runtime,
+  initialDelay = 0,
   timeout = 10_000 /* 10s to boot up */,
 ): Promise<build.Build> {
   let res: Response;
@@ -84,13 +85,21 @@
     }, getFunctionDiscoveryTimeout() || timeout);
   });
 
+  // Initial delay to wait for admin server to boot.
+  if (initialDelay > 0) {
+    await new Promise((resolve) => setTimeout(resolve, initialDelay));
+  }
+
+  const url = `http://127.0.0.1:${port}/__/functions.yaml`;
   while (true) {
     try {
-      res = await Promise.race([fetch(`http://127.0.0.1:${port}/__/functions.yaml`), timedOut]);
+      res = await Promise.race([fetch(url), timedOut]);
       break;
     } catch (err: any) {
-      // Allow us to wait until the server is listening.
-      if (err?.code === "ECONNREFUSED") {
+      if (
+        err?.name === "FetchError" ||
+        ["ECONNREFUSED", "ECONNRESET", "ETIMEDOUT"].includes(err?.code)
+      ) {
         continue;
       }
       throw err;

src/deploy/functions/runtimes/python/index.ts

@@ -195,7 +195,12 @@ export class Delegate implements runtimes.RuntimeDelegate {
       });
       const killProcess = await this.serveAdmin(adminPort, envs);
       try {
-        discovered = await discovery.detectFromPort(adminPort, this.projectId, this.runtime);
+        discovered = await discovery.detectFromPort(
+          adminPort,
+          this.projectId,
+          this.runtime,
+          500 /* initialDelay, python startup is slow */,
+        );
       } finally {
         await killProcess();
       }