App Hosting Emulator: Auto-Init Support - Inject hostnames of other emulators into the app hosting emulator

src/emulator/apphosting/serve.ts

@@ -12,6 +12,8 @@
 import { Emulators } from "../types";
 import { getLocalAppHostingConfiguration } from "./config";
 import { resolveProjectPath } from "../../projectPath";
+import { EmulatorRegistry } from "../registry";
+import { setEnvVarsForEmulators } from "../env";
 
 interface StartOptions {
   port?: number;
@@ -34,7 +36,7 @@
     port += 1;
   }
 
   serve(port, options?.startCommand, options?.rootDirectory);
 
   return { hostname, port };
 }
@@ -51,10 +53,11 @@
   const environmentVariablesAsRecord: Record<string, string> = {};
 
   for (const env of apphostingLocalConfig.environmentVariables) {
     environmentVariablesAsRecord[env.variable] = env.value!;
   }
 
   const environmentVariablesToInject = {
+    ...getEmulatorEnvs(),
     ...environmentVariablesAsRecord,
     PORT: port.toString(),
   };
@@ -81,3 +84,11 @@
     family: isIPv4(host) ? "IPv4" : "IPv6",
   });
 }
+
+function getEmulatorEnvs(): Record<string, string> {
+  const envs: Record<string, string> = {};
+  const emulatorInfos = EmulatorRegistry.listRunningWithInfo();
+  setEnvVarsForEmulators(envs, emulatorInfos);
+
+  return envs;
+}