From 1dc91a0223d3200a33c0045efd1f8899517bf86f Mon Sep 17 00:00:00 2001
From: digital88 <digitaldaemon8@gmail.com>
Date: Wed, 12 Mar 2025 23:52:45 +0300
Subject: [PATCH 1/5] feat(gloud) add ability to set cmd flags

---
 .../src/datastore-emulator-container.test.ts  |  8 ++++
 .../src/datastore-emulator-container.ts       | 11 ++++--
 .../src/firestore-emulator-container.test.ts  | 11 +++++-
 .../src/firestore-emulator-container.ts       | 10 +++--
 .../src/generic-emulator-container.test.ts    | 26 +++++++++++++
 .../gcloud/src/generic-emulator-container.ts  | 39 +++++++++++++++++++
 .../src/pubsub-emulator-container.test.ts     |  8 ++++
 .../gcloud/src/pubsub-emulator-container.ts   | 15 ++++---
 8 files changed, 113 insertions(+), 15 deletions(-)
 create mode 100644 packages/modules/gcloud/src/generic-emulator-container.test.ts
 create mode 100644 packages/modules/gcloud/src/generic-emulator-container.ts

diff --git a/packages/modules/gcloud/src/datastore-emulator-container.test.ts b/packages/modules/gcloud/src/datastore-emulator-container.test.ts
index 36384c6e5..dea39a76a 100644
--- a/packages/modules/gcloud/src/datastore-emulator-container.test.ts
+++ b/packages/modules/gcloud/src/datastore-emulator-container.test.ts
@@ -25,6 +25,14 @@ describe("DatastoreEmulatorContainer", { timeout: 240_000 }, () => {
 
   // }
 
+  it("should have default host-port flag and database-mode flag", async (ctx) => {
+    const datastoreEmulatorContainer = new DatastoreEmulatorContainer();
+
+    const flags = datastoreEmulatorContainer.expandFlags();
+
+    expect(flags.trim()).toEqual("--host-port=0.0.0.0:8080 --database-mode=datastore-mode");
+  });
+
   async function checkDatastore(datastoreEmulatorContainer: StartedDatastoreEmulatorContainer) {
     expect(datastoreEmulatorContainer).toBeDefined();
     const testProjectId = "test-project";
diff --git a/packages/modules/gcloud/src/datastore-emulator-container.ts b/packages/modules/gcloud/src/datastore-emulator-container.ts
index 8846c0ab2..847e69b37 100644
--- a/packages/modules/gcloud/src/datastore-emulator-container.ts
+++ b/packages/modules/gcloud/src/datastore-emulator-container.ts
@@ -1,14 +1,17 @@
-import { AbstractStartedContainer, GenericContainer, StartedTestContainer, Wait } from "testcontainers";
+import { AbstractStartedContainer, StartedTestContainer, Wait } from "testcontainers";
+import { GenericGCloudEmulatorContainer } from "./generic-emulator-container";
 
 const EMULATOR_PORT = 8080;
-const CMD = `gcloud beta emulators firestore start --host-port 0.0.0.0:${EMULATOR_PORT} --database-mode=datastore-mode`;
+const CMD = `gcloud beta emulators firestore start`;
 const DEFAULT_IMAGE = "gcr.io/google.com/cloudsdktool/cloud-sdk";
 
-export class DatastoreEmulatorContainer extends GenericContainer {
+export class DatastoreEmulatorContainer extends GenericGCloudEmulatorContainer {
   constructor(image = DEFAULT_IMAGE) {
     super(image);
     this.withExposedPorts(EMULATOR_PORT)
-      .withCommand(["/bin/sh", "-c", CMD])
+      .withFlag("host-port", `0.0.0.0:${EMULATOR_PORT}`)
+      .withFlag("database-mode", `datastore-mode`)
+      .withCommand(["/bin/sh", "-c", `${CMD} ${this.expandFlags()}`])
       .withWaitStrategy(Wait.forLogMessage(RegExp(".*running.*"), 1))
       .withStartupTimeout(120_000);
   }
diff --git a/packages/modules/gcloud/src/firestore-emulator-container.test.ts b/packages/modules/gcloud/src/firestore-emulator-container.test.ts
index 2b1829ec8..7c98b0e69 100644
--- a/packages/modules/gcloud/src/firestore-emulator-container.test.ts
+++ b/packages/modules/gcloud/src/firestore-emulator-container.test.ts
@@ -2,7 +2,8 @@ import * as admin from "firebase-admin";
 import { FirestoreEmulatorContainer, StartedFirestoreEmulatorContainer } from "./firestore-emulator-container";
 
 describe("FirestoreEmulatorContainer", { timeout: 240_000 }, () => {
-  afterEach(async () => {
+  afterEach(async (ctx) => {
+    if (ctx.task.name === "should have default host-port flag") return;
     await admin.app().delete();
   });
 
@@ -29,6 +30,14 @@ describe("FirestoreEmulatorContainer", { timeout: 240_000 }, () => {
 
   // }
 
+  it("should have default host-port flag", async (ctx) => {
+    const firestoreEmulatorContainer = new FirestoreEmulatorContainer();
+
+    const flags = firestoreEmulatorContainer.expandFlags();
+
+    expect(flags.trim()).toEqual("--host-port=0.0.0.0:8080");
+  });
+
   async function checkFirestore(firestoreEmulatorContainer: StartedFirestoreEmulatorContainer) {
     expect(firestoreEmulatorContainer).toBeDefined();
     const testProjectId = "test-project";
diff --git a/packages/modules/gcloud/src/firestore-emulator-container.ts b/packages/modules/gcloud/src/firestore-emulator-container.ts
index 261dbc234..777ebbebc 100644
--- a/packages/modules/gcloud/src/firestore-emulator-container.ts
+++ b/packages/modules/gcloud/src/firestore-emulator-container.ts
@@ -1,14 +1,16 @@
-import { AbstractStartedContainer, GenericContainer, StartedTestContainer, Wait } from "testcontainers";
+import { AbstractStartedContainer, StartedTestContainer, Wait } from "testcontainers";
+import { GenericGCloudEmulatorContainer } from "./generic-emulator-container";
 
 const EMULATOR_PORT = 8080;
-const CMD = `gcloud beta emulators firestore start --host-port 0.0.0.0:${EMULATOR_PORT}`;
+const CMD = `gcloud beta emulators firestore start`;
 const DEFAULT_IMAGE = "gcr.io/google.com/cloudsdktool/cloud-sdk";
 
-export class FirestoreEmulatorContainer extends GenericContainer {
+export class FirestoreEmulatorContainer extends GenericGCloudEmulatorContainer {
   constructor(image = DEFAULT_IMAGE) {
     super(image);
     this.withExposedPorts(EMULATOR_PORT)
-      .withCommand(["/bin/sh", "-c", CMD])
+      .withFlag("host-port", `0.0.0.0:${EMULATOR_PORT}`)
+      .withCommand(["/bin/sh", "-c", `${CMD} ${this.expandFlags()}`])
       .withWaitStrategy(Wait.forLogMessage(RegExp(".*running.*"), 1))
       .withStartupTimeout(120_000);
   }
diff --git a/packages/modules/gcloud/src/generic-emulator-container.test.ts b/packages/modules/gcloud/src/generic-emulator-container.test.ts
new file mode 100644
index 000000000..b8936bc4e
--- /dev/null
+++ b/packages/modules/gcloud/src/generic-emulator-container.test.ts
@@ -0,0 +1,26 @@
+
+import { GenericGCloudEmulatorContainer } from "./generic-emulator-container";
+
+const IMAGE = "gcr.io/google.com/cloudsdktool/cloud-sdk"
+
+describe("GenericGCloudEmulatorContainer", { timeout: 240_000 }, () => {
+    it("should have all flags added", async () => {
+        const genericGCloudEmulatorContainer = new GenericGCloudEmulatorContainer(IMAGE)
+            .withFlag("database-mode", "firestore-native");
+
+        const flags = genericGCloudEmulatorContainer.expandFlags();
+
+        expect(flags.trim()).toEqual("--database-mode=firestore-native");
+    });
+
+    it("should overwrite flag if added more than once", async () => {
+        const genericGCloudEmulatorContainer = new GenericGCloudEmulatorContainer(IMAGE)
+            .withFlag("database-mode", "firestore-native")
+            .withFlag("database-mode", "datastore-mode")
+            .withFlag("database-mode", "datastore-mode");
+
+        const flags = genericGCloudEmulatorContainer.expandFlags();
+
+        expect(flags.trim()).toEqual("--database-mode=datastore-mode");
+    });
+});
diff --git a/packages/modules/gcloud/src/generic-emulator-container.ts b/packages/modules/gcloud/src/generic-emulator-container.ts
new file mode 100644
index 000000000..665342cc9
--- /dev/null
+++ b/packages/modules/gcloud/src/generic-emulator-container.ts
@@ -0,0 +1,39 @@
+import { GenericContainer } from "testcontainers";
+
+export class GenericGCloudEmulatorContainer extends GenericContainer {
+    private flags: { name: string, value: string }[] = []
+
+    constructor(image: string) {
+        super(image);
+    }
+
+    /**
+     * Adds flag name and value as argument to emulator start command.
+     * Adding same flag name twice replaces existing flag value.
+     * Provided flag name may optionally contain -- prefix.
+     */
+    public withFlag(name: string, value: string): this {
+        if (!name) throw new Error("Flag name must be set.")
+        // replace flag if it already exists
+        const idx = this.flags.findIndex(f => f.name == this.trimFlagName(name))
+        if (idx >= 0)
+            this.flags = [...this.flags.slice(0, idx), ...this.flags.slice(idx + 1)]
+        this.flags.push({ name, value });
+        return this
+    }
+
+    private trimFlagName(name: string): string {
+        return name?.startsWith('--') ? name.slice(2) : name
+    }
+
+    private flagToString(f: { name: string, value: string }): string {
+        return `--${this.trimFlagName(f.name)}=${f.value}`
+    }
+
+    /**
+     * @return all flags provided to run this emulator instance, concatenated to string.
+     */
+    public expandFlags(): string {
+        return `${this.flags.reduce((p, c) => p + ' ' + this.flagToString(c), '')}`
+    }
+}
diff --git a/packages/modules/gcloud/src/pubsub-emulator-container.test.ts b/packages/modules/gcloud/src/pubsub-emulator-container.test.ts
index a56c3f5f6..c407c0ad9 100644
--- a/packages/modules/gcloud/src/pubsub-emulator-container.test.ts
+++ b/packages/modules/gcloud/src/pubsub-emulator-container.test.ts
@@ -10,6 +10,14 @@ describe("PubSubEmulatorContainer", { timeout: 240_000 }, () => {
     await pubsubEmulatorContainer.stop();
   });
 
+  it("should have default host-port flag", async () => {
+    const pubsubEmulatorContainer = new PubSubEmulatorContainer();
+
+    const flags = pubsubEmulatorContainer.expandFlags();
+
+    expect(flags.trim()).toEqual("--host-port=0.0.0.0:8085");
+  });
+
   async function checkPubSub(pubsubEmulatorContainer: StartedPubSubEmulatorContainer) {
     expect(pubsubEmulatorContainer).toBeDefined();
 
diff --git a/packages/modules/gcloud/src/pubsub-emulator-container.ts b/packages/modules/gcloud/src/pubsub-emulator-container.ts
index 4f99165a8..9e78acef5 100644
--- a/packages/modules/gcloud/src/pubsub-emulator-container.ts
+++ b/packages/modules/gcloud/src/pubsub-emulator-container.ts
@@ -1,22 +1,24 @@
 import type { StartedTestContainer } from "testcontainers";
-import { AbstractStartedContainer, GenericContainer, Wait } from "testcontainers";
+import { AbstractStartedContainer, Wait } from "testcontainers";
+import { GenericGCloudEmulatorContainer } from "./generic-emulator-container";
 
 const EMULATOR_PORT = 8085;
-const CMD = "gcloud beta emulators pubsub start --host-port 0.0.0.0:8085";
+const CMD = "gcloud beta emulators pubsub start";
 const DEFAULT_IMAGE = "gcr.io/google.com/cloudsdktool/google-cloud-cli";
 
-export class PubSubEmulatorContainer extends GenericContainer {
+export class PubSubEmulatorContainer extends GenericGCloudEmulatorContainer {
   private _projectId?: string;
 
   constructor(image = DEFAULT_IMAGE) {
     super(image);
 
     this.withExposedPorts(EMULATOR_PORT)
+      .withFlag("host-port", `0.0.0.0:${EMULATOR_PORT}`)
       .withWaitStrategy(Wait.forLogMessage(/Server started/g, 1))
       .withStartupTimeout(120_000);
   }
 
-  public withProjectId(projectId: string): PubSubEmulatorContainer {
+  public withProjectId(projectId: string): this {
     this._projectId = projectId;
     return this;
   }
@@ -24,8 +26,9 @@ export class PubSubEmulatorContainer extends GenericContainer {
   public override async start(): Promise<StartedPubSubEmulatorContainer> {
     // Determine the valid command-line prompt when starting the Pub/Sub emulator
     const selectedProjectId = this._projectId ?? "test-project";
-    const commandLine = `${CMD} --project=${selectedProjectId}`;
-    this.withCommand(["/bin/sh", "-c", commandLine]);
+    this
+      .withFlag("project", selectedProjectId)
+      .withCommand(["/bin/sh", "-c", `${CMD} ${this.expandFlags()}`]);
 
     return new StartedPubSubEmulatorContainer(await super.start(), selectedProjectId);
   }

From b9340fa3c9c194f7ec117920eb8b9c8663fa5270 Mon Sep 17 00:00:00 2001
From: digital88 <digitaldaemon8@gmail.com>
Date: Thu, 13 Mar 2025 22:10:59 +0300
Subject: [PATCH 2/5] refactored approach to flags

---
 .../src/datastore-emulator-container.test.ts  | 26 +++++++-
 .../src/datastore-emulator-container.ts       | 34 ++++++++--
 .../gcloud/src/emulator-flags-manager.test.ts | 62 +++++++++++++++++++
 .../gcloud/src/emulator-flags-manager.ts      | 42 +++++++++++++
 .../src/firestore-emulator-container.test.ts  | 28 ++++++++-
 .../src/firestore-emulator-container.ts       | 34 ++++++++--
 .../src/generic-emulator-container.test.ts    | 26 --------
 .../gcloud/src/generic-emulator-container.ts  | 39 ------------
 .../src/pubsub-emulator-container.test.ts     | 21 ++++++-
 .../gcloud/src/pubsub-emulator-container.ts   | 39 +++++++++---
 10 files changed, 264 insertions(+), 87 deletions(-)
 create mode 100644 packages/modules/gcloud/src/emulator-flags-manager.test.ts
 create mode 100644 packages/modules/gcloud/src/emulator-flags-manager.ts
 delete mode 100644 packages/modules/gcloud/src/generic-emulator-container.test.ts
 delete mode 100644 packages/modules/gcloud/src/generic-emulator-container.ts

diff --git a/packages/modules/gcloud/src/datastore-emulator-container.test.ts b/packages/modules/gcloud/src/datastore-emulator-container.test.ts
index dea39a76a..edea6da33 100644
--- a/packages/modules/gcloud/src/datastore-emulator-container.test.ts
+++ b/packages/modules/gcloud/src/datastore-emulator-container.test.ts
@@ -1,4 +1,5 @@
 import { Datastore } from "@google-cloud/datastore";
+import { Wait } from "testcontainers";
 import { DatastoreEmulatorContainer, StartedDatastoreEmulatorContainer } from "./datastore-emulator-container";
 
 describe("DatastoreEmulatorContainer", { timeout: 240_000 }, () => {
@@ -25,14 +26,35 @@ describe("DatastoreEmulatorContainer", { timeout: 240_000 }, () => {
 
   // }
 
-  it("should have default host-port flag and database-mode flag", async (ctx) => {
+  it("should have default host-port flag and database-mode flag", async () => {
     const datastoreEmulatorContainer = new DatastoreEmulatorContainer();
 
-    const flags = datastoreEmulatorContainer.expandFlags();
+    const flags = datastoreEmulatorContainer["flagsManager"].expandFlags();
 
     expect(flags.trim()).toEqual("--host-port=0.0.0.0:8080 --database-mode=datastore-mode");
   });
 
+  it("should be able to add flags after creating container", async () => {
+    const datastoreEmulatorContainer = new DatastoreEmulatorContainer();
+    // clear all default flags
+    datastoreEmulatorContainer["flagsManager"].clearFlags();
+
+    // add some new flags
+    const flags = datastoreEmulatorContainer
+      .withFlag("host-port", "0.0.0.0:8080")
+      .withFlag("database-mode", "datastore-mode")
+      ["flagsManager"].expandFlags();
+
+    // check new added flags exists
+    expect(flags.trim()).toEqual("--host-port=0.0.0.0:8080 --database-mode=datastore-mode");
+
+    // check that container start command uses latest flags string
+    const startedContainer = await datastoreEmulatorContainer
+      .withWaitStrategy(Wait.forLogMessage(/.* start --host=0.0.0.0 --port=8080 --database-mode=datastore-mode/, 1))
+      .start();
+    await startedContainer.stop();
+  });
+
   async function checkDatastore(datastoreEmulatorContainer: StartedDatastoreEmulatorContainer) {
     expect(datastoreEmulatorContainer).toBeDefined();
     const testProjectId = "test-project";
diff --git a/packages/modules/gcloud/src/datastore-emulator-container.ts b/packages/modules/gcloud/src/datastore-emulator-container.ts
index 847e69b37..25b801e36 100644
--- a/packages/modules/gcloud/src/datastore-emulator-container.ts
+++ b/packages/modules/gcloud/src/datastore-emulator-container.ts
@@ -1,21 +1,47 @@
-import { AbstractStartedContainer, StartedTestContainer, Wait } from "testcontainers";
-import { GenericGCloudEmulatorContainer } from "./generic-emulator-container";
+import { AbstractStartedContainer, GenericContainer, StartedTestContainer, Wait } from "testcontainers";
+import { EmulatorFlagsManager } from "./emulator-flags-manager";
 
 const EMULATOR_PORT = 8080;
 const CMD = `gcloud beta emulators firestore start`;
 const DEFAULT_IMAGE = "gcr.io/google.com/cloudsdktool/cloud-sdk";
 
-export class DatastoreEmulatorContainer extends GenericGCloudEmulatorContainer {
+export class DatastoreEmulatorContainer extends GenericContainer {
+  private readonly _flagsManager: EmulatorFlagsManager;
   constructor(image = DEFAULT_IMAGE) {
     super(image);
+    this._flagsManager = new EmulatorFlagsManager();
     this.withExposedPorts(EMULATOR_PORT)
       .withFlag("host-port", `0.0.0.0:${EMULATOR_PORT}`)
       .withFlag("database-mode", `datastore-mode`)
-      .withCommand(["/bin/sh", "-c", `${CMD} ${this.expandFlags()}`])
+      // explicitly call withCommand() fn here
+      // it will be called implicitly inside prev withFlag() call
+      .withCommand(["/bin/sh", "-c", this.getCmd()])
       .withWaitStrategy(Wait.forLogMessage(RegExp(".*running.*"), 1))
       .withStartupTimeout(120_000);
   }
 
+  private getCmd(): string {
+    return `${CMD} ${this.flagsManager.expandFlags()}`;
+  }
+
+  private get flagsManager() {
+    return this._flagsManager;
+  }
+
+  /**
+   * Adds flag as argument to emulator start command.
+   * Adding same flag name twice replaces existing flag value.
+   * @param name flag name. Must be set to non-empty string. May optionally contain -- prefix.
+   * @param value flag value. May be empty string.
+   * @returns this instance for chaining.
+   */
+  public withFlag(name: string, value: string) {
+    this.flagsManager.withFlag(name, value);
+    // we need to 'refresh' command as we add new flag
+    this.withCommand(["/bin/sh", "-c", this.getCmd()]);
+    return this;
+  }
+
   public override async start(): Promise<StartedDatastoreEmulatorContainer> {
     return new StartedDatastoreEmulatorContainer(await super.start());
   }
diff --git a/packages/modules/gcloud/src/emulator-flags-manager.test.ts b/packages/modules/gcloud/src/emulator-flags-manager.test.ts
new file mode 100644
index 000000000..1c7019826
--- /dev/null
+++ b/packages/modules/gcloud/src/emulator-flags-manager.test.ts
@@ -0,0 +1,62 @@
+import { EmulatorFlagsManager } from "./emulator-flags-manager";
+
+describe("EmulatorFlagsManager", () => {
+  it("should add flag without --", async () => {
+    const flagsManager = new EmulatorFlagsManager().withFlag("database-mode", "firestore-native");
+
+    const flags = flagsManager.expandFlags();
+
+    expect(flags.trim()).toEqual("--database-mode=firestore-native");
+  });
+
+  it("should add flag with --", async () => {
+    const flagsManager = new EmulatorFlagsManager().withFlag("--database-mode", "firestore-native");
+
+    const flags = flagsManager.expandFlags();
+
+    expect(flags.trim()).toEqual("--database-mode=firestore-native");
+  });
+
+  it("should add many flags", async () => {
+    const flagsManager = new EmulatorFlagsManager()
+      .withFlag("database-mode", "firestore-native")
+      .withFlag("--host-port", "0.0.0.0:8080");
+
+    const flags = flagsManager.expandFlags();
+
+    expect(flags.trim()).toEqual("--database-mode=firestore-native --host-port=0.0.0.0:8080");
+  });
+
+  it("should overwrite same flag if added more than once", async () => {
+    const flagsManager = new EmulatorFlagsManager()
+      .withFlag("database-mode", "firestore-native")
+      .withFlag("--database-mode", "datastore-mode");
+
+    const flags = flagsManager.expandFlags();
+
+    expect(flags.trim()).toEqual("--database-mode=datastore-mode");
+  });
+
+  it("should add flag with no value", async () => {
+    const flagsManager = new EmulatorFlagsManager().withFlag("database-mode", "").withFlag("--host-port", "");
+
+    const flags = flagsManager.expandFlags();
+
+    expect(flags.trim()).toEqual("--database-mode= --host-port=");
+  });
+
+  it("should throw if flag name not set", async () => {
+    expect(() => new EmulatorFlagsManager().withFlag("", "firestore-native")).toThrowError();
+  });
+
+  it("should clear all flags added", async () => {
+    const flagsManager = new EmulatorFlagsManager()
+      .withFlag("database-mode", "firestore-native")
+      .withFlag("host-port", "0.0.0.0:8080");
+
+    flagsManager.clearFlags();
+    const flags = flagsManager.expandFlags();
+
+    expect(flags.trim()).toEqual("");
+  });
+});
diff --git a/packages/modules/gcloud/src/emulator-flags-manager.ts b/packages/modules/gcloud/src/emulator-flags-manager.ts
new file mode 100644
index 000000000..8fb004dbd
--- /dev/null
+++ b/packages/modules/gcloud/src/emulator-flags-manager.ts
@@ -0,0 +1,42 @@
+export class EmulatorFlagsManager {
+  private flags: { name: string; value: string }[] = [];
+
+  /**
+   * Adds flag as argument to emulator start command.
+   * Adding same flag name twice replaces existing flag value.
+   * @param name flag name. Must be set to non-empty string. May optionally contain -- prefix.
+   * @param value flag value. May be empty string.
+   * @returns this instance for chaining.
+   */
+  public withFlag(name: string, value: string): this {
+    if (!name) throw new Error("Flag name must be set.");
+    // replace flag if it already exists
+    const idx = this.flags.findIndex((f) => f.name == this.trimFlagName(name));
+    if (idx >= 0) this.flags = [...this.flags.slice(0, idx), ...this.flags.slice(idx + 1)];
+    this.flags.push({ name, value });
+    return this;
+  }
+
+  private trimFlagName(name: string): string {
+    return name?.startsWith("--") ? name.slice(2) : name;
+  }
+
+  private flagToString(f: { name: string; value: string }): string {
+    return `--${this.trimFlagName(f.name)}=${f.value}`;
+  }
+
+  /**
+   *
+   * @returns string with all flag names and values, concatenated in same order they were added.
+   */
+  public expandFlags(): string {
+    return `${this.flags.reduce((p, c) => p + " " + this.flagToString(c), "")}`;
+  }
+
+  /**
+   * Clears all added flags.
+   */
+  public clearFlags() {
+    this.flags = [];
+  }
+}
diff --git a/packages/modules/gcloud/src/firestore-emulator-container.test.ts b/packages/modules/gcloud/src/firestore-emulator-container.test.ts
index 7c98b0e69..e8e6ab275 100644
--- a/packages/modules/gcloud/src/firestore-emulator-container.test.ts
+++ b/packages/modules/gcloud/src/firestore-emulator-container.test.ts
@@ -1,9 +1,10 @@
 import * as admin from "firebase-admin";
+import { Wait } from "testcontainers";
 import { FirestoreEmulatorContainer, StartedFirestoreEmulatorContainer } from "./firestore-emulator-container";
 
 describe("FirestoreEmulatorContainer", { timeout: 240_000 }, () => {
   afterEach(async (ctx) => {
-    if (ctx.task.name === "should have default host-port flag") return;
+    if (!["should work using default version", "should work using version 468.0.0"].includes(ctx.task.name)) return;
     await admin.app().delete();
   });
 
@@ -30,14 +31,35 @@ describe("FirestoreEmulatorContainer", { timeout: 240_000 }, () => {
 
   // }
 
-  it("should have default host-port flag", async (ctx) => {
+  it("should have default host-port flag", async () => {
     const firestoreEmulatorContainer = new FirestoreEmulatorContainer();
 
-    const flags = firestoreEmulatorContainer.expandFlags();
+    const flags = firestoreEmulatorContainer["flagsManager"].expandFlags();
 
     expect(flags.trim()).toEqual("--host-port=0.0.0.0:8080");
   });
 
+  it("should be able to add flags after creating container", async () => {
+    const firestoreEmulatorContainer = new FirestoreEmulatorContainer();
+    // clear all default flags
+    firestoreEmulatorContainer["flagsManager"].clearFlags();
+
+    // add some new flags
+    const flags = firestoreEmulatorContainer
+      .withFlag("host-port", "0.0.0.0:8080")
+      .withFlag("database-mode", "datastore-mode")
+      ["flagsManager"].expandFlags();
+
+    // check new added flags exists
+    expect(flags.trim()).toEqual("--host-port=0.0.0.0:8080 --database-mode=datastore-mode");
+
+    // check that container start command uses latest flags string
+    const startedContainer = await firestoreEmulatorContainer
+      .withWaitStrategy(Wait.forLogMessage(/.* start --host=0.0.0.0 --port=8080 --database-mode=datastore-mode/, 1))
+      .start();
+    await startedContainer.stop();
+  });
+
   async function checkFirestore(firestoreEmulatorContainer: StartedFirestoreEmulatorContainer) {
     expect(firestoreEmulatorContainer).toBeDefined();
     const testProjectId = "test-project";
diff --git a/packages/modules/gcloud/src/firestore-emulator-container.ts b/packages/modules/gcloud/src/firestore-emulator-container.ts
index 777ebbebc..2eab7aec6 100644
--- a/packages/modules/gcloud/src/firestore-emulator-container.ts
+++ b/packages/modules/gcloud/src/firestore-emulator-container.ts
@@ -1,20 +1,46 @@
-import { AbstractStartedContainer, StartedTestContainer, Wait } from "testcontainers";
-import { GenericGCloudEmulatorContainer } from "./generic-emulator-container";
+import { AbstractStartedContainer, GenericContainer, StartedTestContainer, Wait } from "testcontainers";
+import { EmulatorFlagsManager } from "./emulator-flags-manager";
 
 const EMULATOR_PORT = 8080;
 const CMD = `gcloud beta emulators firestore start`;
 const DEFAULT_IMAGE = "gcr.io/google.com/cloudsdktool/cloud-sdk";
 
-export class FirestoreEmulatorContainer extends GenericGCloudEmulatorContainer {
+export class FirestoreEmulatorContainer extends GenericContainer {
+  private readonly _flagsManager: EmulatorFlagsManager;
   constructor(image = DEFAULT_IMAGE) {
     super(image);
+    this._flagsManager = new EmulatorFlagsManager();
     this.withExposedPorts(EMULATOR_PORT)
       .withFlag("host-port", `0.0.0.0:${EMULATOR_PORT}`)
-      .withCommand(["/bin/sh", "-c", `${CMD} ${this.expandFlags()}`])
+      // explicitly call withCommand() fn here
+      // it will be called implicitly inside prev withFlag() call
+      .withCommand(["/bin/sh", "-c", this.getCmd()])
       .withWaitStrategy(Wait.forLogMessage(RegExp(".*running.*"), 1))
       .withStartupTimeout(120_000);
   }
 
+  private getCmd(): string {
+    return `${CMD} ${this.flagsManager.expandFlags()}`;
+  }
+
+  private get flagsManager() {
+    return this._flagsManager;
+  }
+
+  /**
+   * Adds flag as argument to emulator start command.
+   * Adding same flag name twice replaces existing flag value.
+   * @param name flag name. Must be set to non-empty string. May optionally contain -- prefix.
+   * @param value flag value. May be empty string.
+   * @returns this instance for chaining.
+   */
+  public withFlag(name: string, value: string) {
+    this.flagsManager.withFlag(name, value);
+    // we need to 'refresh' command as we add new flag
+    this.withCommand(["/bin/sh", "-c", this.getCmd()]);
+    return this;
+  }
+
   public override async start(): Promise<StartedFirestoreEmulatorContainer> {
     return new StartedFirestoreEmulatorContainer(await super.start());
   }
diff --git a/packages/modules/gcloud/src/generic-emulator-container.test.ts b/packages/modules/gcloud/src/generic-emulator-container.test.ts
deleted file mode 100644
index b8936bc4e..000000000
--- a/packages/modules/gcloud/src/generic-emulator-container.test.ts
+++ /dev/null
@@ -1,26 +0,0 @@
-
-import { GenericGCloudEmulatorContainer } from "./generic-emulator-container";
-
-const IMAGE = "gcr.io/google.com/cloudsdktool/cloud-sdk"
-
-describe("GenericGCloudEmulatorContainer", { timeout: 240_000 }, () => {
-    it("should have all flags added", async () => {
-        const genericGCloudEmulatorContainer = new GenericGCloudEmulatorContainer(IMAGE)
-            .withFlag("database-mode", "firestore-native");
-
-        const flags = genericGCloudEmulatorContainer.expandFlags();
-
-        expect(flags.trim()).toEqual("--database-mode=firestore-native");
-    });
-
-    it("should overwrite flag if added more than once", async () => {
-        const genericGCloudEmulatorContainer = new GenericGCloudEmulatorContainer(IMAGE)
-            .withFlag("database-mode", "firestore-native")
-            .withFlag("database-mode", "datastore-mode")
-            .withFlag("database-mode", "datastore-mode");
-
-        const flags = genericGCloudEmulatorContainer.expandFlags();
-
-        expect(flags.trim()).toEqual("--database-mode=datastore-mode");
-    });
-});
diff --git a/packages/modules/gcloud/src/generic-emulator-container.ts b/packages/modules/gcloud/src/generic-emulator-container.ts
deleted file mode 100644
index 665342cc9..000000000
--- a/packages/modules/gcloud/src/generic-emulator-container.ts
+++ /dev/null
@@ -1,39 +0,0 @@
-import { GenericContainer } from "testcontainers";
-
-export class GenericGCloudEmulatorContainer extends GenericContainer {
-    private flags: { name: string, value: string }[] = []
-
-    constructor(image: string) {
-        super(image);
-    }
-
-    /**
-     * Adds flag name and value as argument to emulator start command.
-     * Adding same flag name twice replaces existing flag value.
-     * Provided flag name may optionally contain -- prefix.
-     */
-    public withFlag(name: string, value: string): this {
-        if (!name) throw new Error("Flag name must be set.")
-        // replace flag if it already exists
-        const idx = this.flags.findIndex(f => f.name == this.trimFlagName(name))
-        if (idx >= 0)
-            this.flags = [...this.flags.slice(0, idx), ...this.flags.slice(idx + 1)]
-        this.flags.push({ name, value });
-        return this
-    }
-
-    private trimFlagName(name: string): string {
-        return name?.startsWith('--') ? name.slice(2) : name
-    }
-
-    private flagToString(f: { name: string, value: string }): string {
-        return `--${this.trimFlagName(f.name)}=${f.value}`
-    }
-
-    /**
-     * @return all flags provided to run this emulator instance, concatenated to string.
-     */
-    public expandFlags(): string {
-        return `${this.flags.reduce((p, c) => p + ' ' + this.flagToString(c), '')}`
-    }
-}
diff --git a/packages/modules/gcloud/src/pubsub-emulator-container.test.ts b/packages/modules/gcloud/src/pubsub-emulator-container.test.ts
index c407c0ad9..9a2a3e463 100644
--- a/packages/modules/gcloud/src/pubsub-emulator-container.test.ts
+++ b/packages/modules/gcloud/src/pubsub-emulator-container.test.ts
@@ -1,4 +1,5 @@
 import { PubSub } from "@google-cloud/pubsub";
+import { Wait } from "testcontainers";
 import { PubSubEmulatorContainer, StartedPubSubEmulatorContainer } from "./pubsub-emulator-container";
 
 describe("PubSubEmulatorContainer", { timeout: 240_000 }, () => {
@@ -13,11 +14,29 @@ describe("PubSubEmulatorContainer", { timeout: 240_000 }, () => {
   it("should have default host-port flag", async () => {
     const pubsubEmulatorContainer = new PubSubEmulatorContainer();
 
-    const flags = pubsubEmulatorContainer.expandFlags();
+    const flags = pubsubEmulatorContainer["flagsManager"].expandFlags();
 
     expect(flags.trim()).toEqual("--host-port=0.0.0.0:8085");
   });
 
+  it("should be able to add flags after creating container", async () => {
+    const pubsubEmulatorContainer = new PubSubEmulatorContainer();
+    // clear all default flags
+    pubsubEmulatorContainer["flagsManager"].clearFlags();
+
+    // add some new flags
+    const flags = pubsubEmulatorContainer.withFlag("host-port", "0.0.0.0:8081")["flagsManager"].expandFlags();
+
+    // check new added flags exists
+    expect(flags.trim()).toEqual("--host-port=0.0.0.0:8081");
+
+    // check that container start command uses latest flags string
+    const startedContainer = await pubsubEmulatorContainer
+      .withWaitStrategy(Wait.forLogMessage(/.* listening on 8081/, 1))
+      .start();
+    await startedContainer.stop();
+  });
+
   async function checkPubSub(pubsubEmulatorContainer: StartedPubSubEmulatorContainer) {
     expect(pubsubEmulatorContainer).toBeDefined();
 
diff --git a/packages/modules/gcloud/src/pubsub-emulator-container.ts b/packages/modules/gcloud/src/pubsub-emulator-container.ts
index 9e78acef5..b82ff8fb5 100644
--- a/packages/modules/gcloud/src/pubsub-emulator-container.ts
+++ b/packages/modules/gcloud/src/pubsub-emulator-container.ts
@@ -1,23 +1,45 @@
-import type { StartedTestContainer } from "testcontainers";
-import { AbstractStartedContainer, Wait } from "testcontainers";
-import { GenericGCloudEmulatorContainer } from "./generic-emulator-container";
+import { AbstractStartedContainer, GenericContainer, StartedTestContainer, Wait } from "testcontainers";
+import { EmulatorFlagsManager } from "./emulator-flags-manager";
 
 const EMULATOR_PORT = 8085;
 const CMD = "gcloud beta emulators pubsub start";
 const DEFAULT_IMAGE = "gcr.io/google.com/cloudsdktool/google-cloud-cli";
 
-export class PubSubEmulatorContainer extends GenericGCloudEmulatorContainer {
+export class PubSubEmulatorContainer extends GenericContainer {
+  private readonly _flagsManager: EmulatorFlagsManager;
   private _projectId?: string;
 
   constructor(image = DEFAULT_IMAGE) {
     super(image);
-
+    this._flagsManager = new EmulatorFlagsManager();
     this.withExposedPorts(EMULATOR_PORT)
       .withFlag("host-port", `0.0.0.0:${EMULATOR_PORT}`)
       .withWaitStrategy(Wait.forLogMessage(/Server started/g, 1))
       .withStartupTimeout(120_000);
   }
 
+  private getCmd(): string {
+    return `${CMD} ${this.flagsManager.expandFlags()}`;
+  }
+
+  private get flagsManager() {
+    return this._flagsManager;
+  }
+
+  /**
+   * Adds flag as argument to emulator start command.
+   * Adding same flag name twice replaces existing flag value.
+   * @param name flag name. Must be set to non-empty string. May optionally contain -- prefix.
+   * @param value flag value. May be empty string.
+   * @returns this instance for chaining.
+   */
+  public withFlag(name: string, value: string) {
+    this.flagsManager.withFlag(name, value);
+    // we need to 'refresh' command as we add new flag
+    this.withCommand(["/bin/sh", "-c", this.getCmd()]);
+    return this;
+  }
+
   public withProjectId(projectId: string): this {
     this._projectId = projectId;
     return this;
@@ -26,9 +48,10 @@ export class PubSubEmulatorContainer extends GenericGCloudEmulatorContainer {
   public override async start(): Promise<StartedPubSubEmulatorContainer> {
     // Determine the valid command-line prompt when starting the Pub/Sub emulator
     const selectedProjectId = this._projectId ?? "test-project";
-    this
-      .withFlag("project", selectedProjectId)
-      .withCommand(["/bin/sh", "-c", `${CMD} ${this.expandFlags()}`]);
+    this.withFlag("project", selectedProjectId)
+      // explicitly call withCommand() fn here
+      // it will be called implicitly inside prev withFlag() call
+      .withCommand(["/bin/sh", "-c", this.getCmd()]);
 
     return new StartedPubSubEmulatorContainer(await super.start(), selectedProjectId);
   }

From 94cefb38260b4ab5968db3b61b44d26bbb3800ca Mon Sep 17 00:00:00 2001
From: digital88 <digitaldaemon8@gmail.com>
Date: Tue, 18 Mar 2025 00:56:38 +0300
Subject: [PATCH 3/5] fixed after review

---
 .../src/datastore-emulator-container.test.ts  | 30 -----------------
 .../src/datastore-emulator-container.ts       |  9 ++---
 .../gcloud/src/emulator-flags-manager.test.ts |  2 +-
 .../gcloud/src/emulator-flags-manager.ts      | 20 ++++-------
 .../src/firestore-emulator-container.test.ts  | 33 +------------------
 .../src/firestore-emulator-container.ts       |  9 ++---
 .../src/pubsub-emulator-container.test.ts     | 27 ---------------
 .../gcloud/src/pubsub-emulator-container.ts   |  5 +--
 8 files changed, 16 insertions(+), 119 deletions(-)

diff --git a/packages/modules/gcloud/src/datastore-emulator-container.test.ts b/packages/modules/gcloud/src/datastore-emulator-container.test.ts
index edea6da33..36384c6e5 100644
--- a/packages/modules/gcloud/src/datastore-emulator-container.test.ts
+++ b/packages/modules/gcloud/src/datastore-emulator-container.test.ts
@@ -1,5 +1,4 @@
 import { Datastore } from "@google-cloud/datastore";
-import { Wait } from "testcontainers";
 import { DatastoreEmulatorContainer, StartedDatastoreEmulatorContainer } from "./datastore-emulator-container";
 
 describe("DatastoreEmulatorContainer", { timeout: 240_000 }, () => {
@@ -26,35 +25,6 @@ describe("DatastoreEmulatorContainer", { timeout: 240_000 }, () => {
 
   // }
 
-  it("should have default host-port flag and database-mode flag", async () => {
-    const datastoreEmulatorContainer = new DatastoreEmulatorContainer();
-
-    const flags = datastoreEmulatorContainer["flagsManager"].expandFlags();
-
-    expect(flags.trim()).toEqual("--host-port=0.0.0.0:8080 --database-mode=datastore-mode");
-  });
-
-  it("should be able to add flags after creating container", async () => {
-    const datastoreEmulatorContainer = new DatastoreEmulatorContainer();
-    // clear all default flags
-    datastoreEmulatorContainer["flagsManager"].clearFlags();
-
-    // add some new flags
-    const flags = datastoreEmulatorContainer
-      .withFlag("host-port", "0.0.0.0:8080")
-      .withFlag("database-mode", "datastore-mode")
-      ["flagsManager"].expandFlags();
-
-    // check new added flags exists
-    expect(flags.trim()).toEqual("--host-port=0.0.0.0:8080 --database-mode=datastore-mode");
-
-    // check that container start command uses latest flags string
-    const startedContainer = await datastoreEmulatorContainer
-      .withWaitStrategy(Wait.forLogMessage(/.* start --host=0.0.0.0 --port=8080 --database-mode=datastore-mode/, 1))
-      .start();
-    await startedContainer.stop();
-  });
-
   async function checkDatastore(datastoreEmulatorContainer: StartedDatastoreEmulatorContainer) {
     expect(datastoreEmulatorContainer).toBeDefined();
     const testProjectId = "test-project";
diff --git a/packages/modules/gcloud/src/datastore-emulator-container.ts b/packages/modules/gcloud/src/datastore-emulator-container.ts
index 25b801e36..151091908 100644
--- a/packages/modules/gcloud/src/datastore-emulator-container.ts
+++ b/packages/modules/gcloud/src/datastore-emulator-container.ts
@@ -13,10 +13,7 @@ export class DatastoreEmulatorContainer extends GenericContainer {
     this.withExposedPorts(EMULATOR_PORT)
       .withFlag("host-port", `0.0.0.0:${EMULATOR_PORT}`)
       .withFlag("database-mode", `datastore-mode`)
-      // explicitly call withCommand() fn here
-      // it will be called implicitly inside prev withFlag() call
-      .withCommand(["/bin/sh", "-c", this.getCmd()])
-      .withWaitStrategy(Wait.forLogMessage(RegExp(".*running.*"), 1))
+      .withWaitStrategy(Wait.forLogMessage(/.*running.*/, 1))
       .withStartupTimeout(120_000);
   }
 
@@ -37,12 +34,12 @@ export class DatastoreEmulatorContainer extends GenericContainer {
    */
   public withFlag(name: string, value: string) {
     this.flagsManager.withFlag(name, value);
-    // we need to 'refresh' command as we add new flag
-    this.withCommand(["/bin/sh", "-c", this.getCmd()]);
     return this;
   }
 
   public override async start(): Promise<StartedDatastoreEmulatorContainer> {
+    // expand all flags and get final command
+    this.withCommand(["/bin/sh", "-c", this.getCmd()]);
     return new StartedDatastoreEmulatorContainer(await super.start());
   }
 }
diff --git a/packages/modules/gcloud/src/emulator-flags-manager.test.ts b/packages/modules/gcloud/src/emulator-flags-manager.test.ts
index 1c7019826..15df56b5a 100644
--- a/packages/modules/gcloud/src/emulator-flags-manager.test.ts
+++ b/packages/modules/gcloud/src/emulator-flags-manager.test.ts
@@ -42,7 +42,7 @@ describe("EmulatorFlagsManager", () => {
 
     const flags = flagsManager.expandFlags();
 
-    expect(flags.trim()).toEqual("--database-mode= --host-port=");
+    expect(flags.trim()).toEqual("--database-mode --host-port");
   });
 
   it("should throw if flag name not set", async () => {
diff --git a/packages/modules/gcloud/src/emulator-flags-manager.ts b/packages/modules/gcloud/src/emulator-flags-manager.ts
index 8fb004dbd..a8209abef 100644
--- a/packages/modules/gcloud/src/emulator-flags-manager.ts
+++ b/packages/modules/gcloud/src/emulator-flags-manager.ts
@@ -1,5 +1,5 @@
 export class EmulatorFlagsManager {
-  private flags: { name: string; value: string }[] = [];
+  private flags: { [name: string]: string } = {};
 
   /**
    * Adds flag as argument to emulator start command.
@@ -10,19 +10,13 @@ export class EmulatorFlagsManager {
    */
   public withFlag(name: string, value: string): this {
     if (!name) throw new Error("Flag name must be set.");
-    // replace flag if it already exists
-    const idx = this.flags.findIndex((f) => f.name == this.trimFlagName(name));
-    if (idx >= 0) this.flags = [...this.flags.slice(0, idx), ...this.flags.slice(idx + 1)];
-    this.flags.push({ name, value });
+    if (name.startsWith("--")) this.flags[name] = value;
+    else this.flags[`--${name}`] = value;
     return this;
   }
 
-  private trimFlagName(name: string): string {
-    return name?.startsWith("--") ? name.slice(2) : name;
-  }
-
-  private flagToString(f: { name: string; value: string }): string {
-    return `--${this.trimFlagName(f.name)}=${f.value}`;
+  private flagToString(name: string, value: string): string {
+    return `${name}${value ? "=" + value : ""}`;
   }
 
   /**
@@ -30,13 +24,13 @@ export class EmulatorFlagsManager {
    * @returns string with all flag names and values, concatenated in same order they were added.
    */
   public expandFlags(): string {
-    return `${this.flags.reduce((p, c) => p + " " + this.flagToString(c), "")}`;
+    return `${Object.keys(this.flags).reduce((p, c) => p + " " + this.flagToString(c, this.flags[c]), "")}`;
   }
 
   /**
    * Clears all added flags.
    */
   public clearFlags() {
-    this.flags = [];
+    this.flags = {};
   }
 }
diff --git a/packages/modules/gcloud/src/firestore-emulator-container.test.ts b/packages/modules/gcloud/src/firestore-emulator-container.test.ts
index e8e6ab275..2b1829ec8 100644
--- a/packages/modules/gcloud/src/firestore-emulator-container.test.ts
+++ b/packages/modules/gcloud/src/firestore-emulator-container.test.ts
@@ -1,10 +1,8 @@
 import * as admin from "firebase-admin";
-import { Wait } from "testcontainers";
 import { FirestoreEmulatorContainer, StartedFirestoreEmulatorContainer } from "./firestore-emulator-container";
 
 describe("FirestoreEmulatorContainer", { timeout: 240_000 }, () => {
-  afterEach(async (ctx) => {
-    if (!["should work using default version", "should work using version 468.0.0"].includes(ctx.task.name)) return;
+  afterEach(async () => {
     await admin.app().delete();
   });
 
@@ -31,35 +29,6 @@ describe("FirestoreEmulatorContainer", { timeout: 240_000 }, () => {
 
   // }
 
-  it("should have default host-port flag", async () => {
-    const firestoreEmulatorContainer = new FirestoreEmulatorContainer();
-
-    const flags = firestoreEmulatorContainer["flagsManager"].expandFlags();
-
-    expect(flags.trim()).toEqual("--host-port=0.0.0.0:8080");
-  });
-
-  it("should be able to add flags after creating container", async () => {
-    const firestoreEmulatorContainer = new FirestoreEmulatorContainer();
-    // clear all default flags
-    firestoreEmulatorContainer["flagsManager"].clearFlags();
-
-    // add some new flags
-    const flags = firestoreEmulatorContainer
-      .withFlag("host-port", "0.0.0.0:8080")
-      .withFlag("database-mode", "datastore-mode")
-      ["flagsManager"].expandFlags();
-
-    // check new added flags exists
-    expect(flags.trim()).toEqual("--host-port=0.0.0.0:8080 --database-mode=datastore-mode");
-
-    // check that container start command uses latest flags string
-    const startedContainer = await firestoreEmulatorContainer
-      .withWaitStrategy(Wait.forLogMessage(/.* start --host=0.0.0.0 --port=8080 --database-mode=datastore-mode/, 1))
-      .start();
-    await startedContainer.stop();
-  });
-
   async function checkFirestore(firestoreEmulatorContainer: StartedFirestoreEmulatorContainer) {
     expect(firestoreEmulatorContainer).toBeDefined();
     const testProjectId = "test-project";
diff --git a/packages/modules/gcloud/src/firestore-emulator-container.ts b/packages/modules/gcloud/src/firestore-emulator-container.ts
index 2eab7aec6..3ed8e985d 100644
--- a/packages/modules/gcloud/src/firestore-emulator-container.ts
+++ b/packages/modules/gcloud/src/firestore-emulator-container.ts
@@ -12,10 +12,7 @@ export class FirestoreEmulatorContainer extends GenericContainer {
     this._flagsManager = new EmulatorFlagsManager();
     this.withExposedPorts(EMULATOR_PORT)
       .withFlag("host-port", `0.0.0.0:${EMULATOR_PORT}`)
-      // explicitly call withCommand() fn here
-      // it will be called implicitly inside prev withFlag() call
-      .withCommand(["/bin/sh", "-c", this.getCmd()])
-      .withWaitStrategy(Wait.forLogMessage(RegExp(".*running.*"), 1))
+      .withWaitStrategy(Wait.forLogMessage(/.*running.*/, 1))
       .withStartupTimeout(120_000);
   }
 
@@ -36,12 +33,12 @@ export class FirestoreEmulatorContainer extends GenericContainer {
    */
   public withFlag(name: string, value: string) {
     this.flagsManager.withFlag(name, value);
-    // we need to 'refresh' command as we add new flag
-    this.withCommand(["/bin/sh", "-c", this.getCmd()]);
     return this;
   }
 
   public override async start(): Promise<StartedFirestoreEmulatorContainer> {
+    // expand all flags and get final command
+    this.withCommand(["/bin/sh", "-c", this.getCmd()]);
     return new StartedFirestoreEmulatorContainer(await super.start());
   }
 }
diff --git a/packages/modules/gcloud/src/pubsub-emulator-container.test.ts b/packages/modules/gcloud/src/pubsub-emulator-container.test.ts
index 9a2a3e463..a56c3f5f6 100644
--- a/packages/modules/gcloud/src/pubsub-emulator-container.test.ts
+++ b/packages/modules/gcloud/src/pubsub-emulator-container.test.ts
@@ -1,5 +1,4 @@
 import { PubSub } from "@google-cloud/pubsub";
-import { Wait } from "testcontainers";
 import { PubSubEmulatorContainer, StartedPubSubEmulatorContainer } from "./pubsub-emulator-container";
 
 describe("PubSubEmulatorContainer", { timeout: 240_000 }, () => {
@@ -11,32 +10,6 @@ describe("PubSubEmulatorContainer", { timeout: 240_000 }, () => {
     await pubsubEmulatorContainer.stop();
   });
 
-  it("should have default host-port flag", async () => {
-    const pubsubEmulatorContainer = new PubSubEmulatorContainer();
-
-    const flags = pubsubEmulatorContainer["flagsManager"].expandFlags();
-
-    expect(flags.trim()).toEqual("--host-port=0.0.0.0:8085");
-  });
-
-  it("should be able to add flags after creating container", async () => {
-    const pubsubEmulatorContainer = new PubSubEmulatorContainer();
-    // clear all default flags
-    pubsubEmulatorContainer["flagsManager"].clearFlags();
-
-    // add some new flags
-    const flags = pubsubEmulatorContainer.withFlag("host-port", "0.0.0.0:8081")["flagsManager"].expandFlags();
-
-    // check new added flags exists
-    expect(flags.trim()).toEqual("--host-port=0.0.0.0:8081");
-
-    // check that container start command uses latest flags string
-    const startedContainer = await pubsubEmulatorContainer
-      .withWaitStrategy(Wait.forLogMessage(/.* listening on 8081/, 1))
-      .start();
-    await startedContainer.stop();
-  });
-
   async function checkPubSub(pubsubEmulatorContainer: StartedPubSubEmulatorContainer) {
     expect(pubsubEmulatorContainer).toBeDefined();
 
diff --git a/packages/modules/gcloud/src/pubsub-emulator-container.ts b/packages/modules/gcloud/src/pubsub-emulator-container.ts
index b82ff8fb5..86e155822 100644
--- a/packages/modules/gcloud/src/pubsub-emulator-container.ts
+++ b/packages/modules/gcloud/src/pubsub-emulator-container.ts
@@ -35,8 +35,6 @@ export class PubSubEmulatorContainer extends GenericContainer {
    */
   public withFlag(name: string, value: string) {
     this.flagsManager.withFlag(name, value);
-    // we need to 'refresh' command as we add new flag
-    this.withCommand(["/bin/sh", "-c", this.getCmd()]);
     return this;
   }
 
@@ -49,8 +47,7 @@ export class PubSubEmulatorContainer extends GenericContainer {
     // Determine the valid command-line prompt when starting the Pub/Sub emulator
     const selectedProjectId = this._projectId ?? "test-project";
     this.withFlag("project", selectedProjectId)
-      // explicitly call withCommand() fn here
-      // it will be called implicitly inside prev withFlag() call
+      // expand all flags and get final command
       .withCommand(["/bin/sh", "-c", this.getCmd()]);
 
     return new StartedPubSubEmulatorContainer(await super.start(), selectedProjectId);

From d71d67b8b06069d043257c12abb3cf2239392c60 Mon Sep 17 00:00:00 2001
From: Cristian Greco <cristianrgreco@gmail.com>
Date: Tue, 18 Mar 2025 09:33:00 +0000
Subject: [PATCH 4/5] Refactor flag management to base class

---
 .../gcloud/src/abstract-gcloud-emulator.ts    | 35 ++++++++++++++
 .../src/datastore-emulator-container.ts       | 39 ++--------------
 .../src/firestore-emulator-container.ts       | 37 ++-------------
 .../gcloud/src/pubsub-emulator-container.ts   | 46 ++++---------------
 4 files changed, 54 insertions(+), 103 deletions(-)
 create mode 100644 packages/modules/gcloud/src/abstract-gcloud-emulator.ts

diff --git a/packages/modules/gcloud/src/abstract-gcloud-emulator.ts b/packages/modules/gcloud/src/abstract-gcloud-emulator.ts
new file mode 100644
index 000000000..80e8e6a4b
--- /dev/null
+++ b/packages/modules/gcloud/src/abstract-gcloud-emulator.ts
@@ -0,0 +1,35 @@
+import { GenericContainer, Wait } from "testcontainers";
+import { EmulatorFlagsManager } from "./emulator-flags-manager";
+
+export class AbstractGcloudEmulator extends GenericContainer {
+  private readonly flagsManager: EmulatorFlagsManager;
+
+  constructor(
+    image: string,
+    port: number,
+    private readonly cmd: string,
+  ) {
+    super(image);
+    this.flagsManager = new EmulatorFlagsManager();
+    this.withExposedPorts(port)
+      .withFlag("host-port", `0.0.0.0:${port}`)
+      .withWaitStrategy(Wait.forLogMessage(/.*running.*/))
+      .withStartupTimeout(120_000);
+  }
+
+  /**
+   * Adds flag as argument to emulator start command.
+   * Adding same flag name twice replaces existing flag value.
+   * @param name flag name. Must be set to non-empty string. May optionally contain -- prefix.
+   * @param value flag value. May be empty string.
+   * @returns this instance for chaining.
+   */
+  public withFlag(name: string, value: string) {
+    this.flagsManager.withFlag(name, value);
+    return this;
+  }
+
+  public override async beforeContainerCreated(): Promise<void> {
+    this.withCommand(["/bin/sh", "-c", `${this.cmd} ${this.flagsManager.expandFlags()}`]);
+  }
+}
diff --git a/packages/modules/gcloud/src/datastore-emulator-container.ts b/packages/modules/gcloud/src/datastore-emulator-container.ts
index 151091908..a8f5f4b1d 100644
--- a/packages/modules/gcloud/src/datastore-emulator-container.ts
+++ b/packages/modules/gcloud/src/datastore-emulator-container.ts
@@ -1,45 +1,16 @@
-import { AbstractStartedContainer, GenericContainer, StartedTestContainer, Wait } from "testcontainers";
-import { EmulatorFlagsManager } from "./emulator-flags-manager";
+import { AbstractStartedContainer, StartedTestContainer } from "testcontainers";
+import { AbstractGcloudEmulator } from "./abstract-gcloud-emulator";
 
 const EMULATOR_PORT = 8080;
-const CMD = `gcloud beta emulators firestore start`;
 const DEFAULT_IMAGE = "gcr.io/google.com/cloudsdktool/cloud-sdk";
 
-export class DatastoreEmulatorContainer extends GenericContainer {
-  private readonly _flagsManager: EmulatorFlagsManager;
+export class DatastoreEmulatorContainer extends AbstractGcloudEmulator {
   constructor(image = DEFAULT_IMAGE) {
-    super(image);
-    this._flagsManager = new EmulatorFlagsManager();
-    this.withExposedPorts(EMULATOR_PORT)
-      .withFlag("host-port", `0.0.0.0:${EMULATOR_PORT}`)
-      .withFlag("database-mode", `datastore-mode`)
-      .withWaitStrategy(Wait.forLogMessage(/.*running.*/, 1))
-      .withStartupTimeout(120_000);
-  }
-
-  private getCmd(): string {
-    return `${CMD} ${this.flagsManager.expandFlags()}`;
-  }
-
-  private get flagsManager() {
-    return this._flagsManager;
-  }
-
-  /**
-   * Adds flag as argument to emulator start command.
-   * Adding same flag name twice replaces existing flag value.
-   * @param name flag name. Must be set to non-empty string. May optionally contain -- prefix.
-   * @param value flag value. May be empty string.
-   * @returns this instance for chaining.
-   */
-  public withFlag(name: string, value: string) {
-    this.flagsManager.withFlag(name, value);
-    return this;
+    super(image, EMULATOR_PORT, "gcloud beta emulators firestore start");
+    this.withFlag("database-mode", `datastore-mode`);
   }
 
   public override async start(): Promise<StartedDatastoreEmulatorContainer> {
-    // expand all flags and get final command
-    this.withCommand(["/bin/sh", "-c", this.getCmd()]);
     return new StartedDatastoreEmulatorContainer(await super.start());
   }
 }
diff --git a/packages/modules/gcloud/src/firestore-emulator-container.ts b/packages/modules/gcloud/src/firestore-emulator-container.ts
index 3ed8e985d..98a91e89a 100644
--- a/packages/modules/gcloud/src/firestore-emulator-container.ts
+++ b/packages/modules/gcloud/src/firestore-emulator-container.ts
@@ -1,44 +1,15 @@
-import { AbstractStartedContainer, GenericContainer, StartedTestContainer, Wait } from "testcontainers";
-import { EmulatorFlagsManager } from "./emulator-flags-manager";
+import { AbstractStartedContainer, StartedTestContainer } from "testcontainers";
+import { AbstractGcloudEmulator } from "./abstract-gcloud-emulator";
 
 const EMULATOR_PORT = 8080;
-const CMD = `gcloud beta emulators firestore start`;
 const DEFAULT_IMAGE = "gcr.io/google.com/cloudsdktool/cloud-sdk";
 
-export class FirestoreEmulatorContainer extends GenericContainer {
-  private readonly _flagsManager: EmulatorFlagsManager;
+export class FirestoreEmulatorContainer extends AbstractGcloudEmulator {
   constructor(image = DEFAULT_IMAGE) {
-    super(image);
-    this._flagsManager = new EmulatorFlagsManager();
-    this.withExposedPorts(EMULATOR_PORT)
-      .withFlag("host-port", `0.0.0.0:${EMULATOR_PORT}`)
-      .withWaitStrategy(Wait.forLogMessage(/.*running.*/, 1))
-      .withStartupTimeout(120_000);
-  }
-
-  private getCmd(): string {
-    return `${CMD} ${this.flagsManager.expandFlags()}`;
-  }
-
-  private get flagsManager() {
-    return this._flagsManager;
-  }
-
-  /**
-   * Adds flag as argument to emulator start command.
-   * Adding same flag name twice replaces existing flag value.
-   * @param name flag name. Must be set to non-empty string. May optionally contain -- prefix.
-   * @param value flag value. May be empty string.
-   * @returns this instance for chaining.
-   */
-  public withFlag(name: string, value: string) {
-    this.flagsManager.withFlag(name, value);
-    return this;
+    super(image, EMULATOR_PORT, "gcloud beta emulators firestore start");
   }
 
   public override async start(): Promise<StartedFirestoreEmulatorContainer> {
-    // expand all flags and get final command
-    this.withCommand(["/bin/sh", "-c", this.getCmd()]);
     return new StartedFirestoreEmulatorContainer(await super.start());
   }
 }
diff --git a/packages/modules/gcloud/src/pubsub-emulator-container.ts b/packages/modules/gcloud/src/pubsub-emulator-container.ts
index 86e155822..3bb2068bb 100644
--- a/packages/modules/gcloud/src/pubsub-emulator-container.ts
+++ b/packages/modules/gcloud/src/pubsub-emulator-container.ts
@@ -1,41 +1,15 @@
-import { AbstractStartedContainer, GenericContainer, StartedTestContainer, Wait } from "testcontainers";
-import { EmulatorFlagsManager } from "./emulator-flags-manager";
+import { AbstractStartedContainer, StartedTestContainer, Wait } from "testcontainers";
+import { AbstractGcloudEmulator } from "./abstract-gcloud-emulator";
 
 const EMULATOR_PORT = 8085;
-const CMD = "gcloud beta emulators pubsub start";
 const DEFAULT_IMAGE = "gcr.io/google.com/cloudsdktool/google-cloud-cli";
 
-export class PubSubEmulatorContainer extends GenericContainer {
-  private readonly _flagsManager: EmulatorFlagsManager;
+export class PubSubEmulatorContainer extends AbstractGcloudEmulator {
   private _projectId?: string;
 
   constructor(image = DEFAULT_IMAGE) {
-    super(image);
-    this._flagsManager = new EmulatorFlagsManager();
-    this.withExposedPorts(EMULATOR_PORT)
-      .withFlag("host-port", `0.0.0.0:${EMULATOR_PORT}`)
-      .withWaitStrategy(Wait.forLogMessage(/Server started/g, 1))
-      .withStartupTimeout(120_000);
-  }
-
-  private getCmd(): string {
-    return `${CMD} ${this.flagsManager.expandFlags()}`;
-  }
-
-  private get flagsManager() {
-    return this._flagsManager;
-  }
-
-  /**
-   * Adds flag as argument to emulator start command.
-   * Adding same flag name twice replaces existing flag value.
-   * @param name flag name. Must be set to non-empty string. May optionally contain -- prefix.
-   * @param value flag value. May be empty string.
-   * @returns this instance for chaining.
-   */
-  public withFlag(name: string, value: string) {
-    this.flagsManager.withFlag(name, value);
-    return this;
+    super(image, EMULATOR_PORT, "gcloud beta emulators pubsub start");
+    this.withWaitStrategy(Wait.forLogMessage(/Server started/g));
   }
 
   public withProjectId(projectId: string): this {
@@ -44,18 +18,18 @@ export class PubSubEmulatorContainer extends GenericContainer {
   }
 
   public override async start(): Promise<StartedPubSubEmulatorContainer> {
-    // Determine the valid command-line prompt when starting the Pub/Sub emulator
     const selectedProjectId = this._projectId ?? "test-project";
-    this.withFlag("project", selectedProjectId)
-      // expand all flags and get final command
-      .withCommand(["/bin/sh", "-c", this.getCmd()]);
+    this.withFlag("project", selectedProjectId);
 
     return new StartedPubSubEmulatorContainer(await super.start(), selectedProjectId);
   }
 }
 
 export class StartedPubSubEmulatorContainer extends AbstractStartedContainer {
-  constructor(startedTestContainer: StartedTestContainer, private readonly projectId: string) {
+  constructor(
+    startedTestContainer: StartedTestContainer,
+    private readonly projectId: string,
+  ) {
     super(startedTestContainer);
   }
 

From 7b7010467175f211515d974745ab3bd81a8984c1 Mon Sep 17 00:00:00 2001
From: Cristian Greco <cristianrgreco@gmail.com>
Date: Tue, 18 Mar 2025 09:42:47 +0000
Subject: [PATCH 5/5] Naming conventions

---
 packages/modules/gcloud/src/pubsub-emulator-container.ts | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/packages/modules/gcloud/src/pubsub-emulator-container.ts b/packages/modules/gcloud/src/pubsub-emulator-container.ts
index 440cfea69..66196b24a 100644
--- a/packages/modules/gcloud/src/pubsub-emulator-container.ts
+++ b/packages/modules/gcloud/src/pubsub-emulator-container.ts
@@ -5,7 +5,7 @@ const EMULATOR_PORT = 8085;
 const DEFAULT_IMAGE = "gcr.io/google.com/cloudsdktool/google-cloud-cli";
 
 export class PubSubEmulatorContainer extends AbstractGcloudEmulator {
-  private _projectId?: string;
+  private projectId?: string;
 
   constructor(image = DEFAULT_IMAGE) {
     super(image, EMULATOR_PORT, "gcloud beta emulators pubsub start");
@@ -13,12 +13,12 @@ export class PubSubEmulatorContainer extends AbstractGcloudEmulator {
   }
 
   public withProjectId(projectId: string): this {
-    this._projectId = projectId;
+    this.projectId = projectId;
     return this;
   }
 
   public override async start(): Promise<StartedPubSubEmulatorContainer> {
-    const selectedProjectId = this._projectId ?? "test-project";
+    const selectedProjectId = this.projectId ?? "test-project";
     this.withFlag("project", selectedProjectId);
 
     return new StartedPubSubEmulatorContainer(await super.start(), selectedProjectId);