[firestore-emulator: datastore-mode] Namespace queries return empty array

[aalej]

[REQUIRED] Environment info

firebase-tools: v13.6.0

Platform: macOS Sonoma 14.4

node: v20.10.0

gcloud: v470.0.0

cloud-firestore-emulator: v1.19.4

[REQUIRED] Test case

MCVE - https://github.com/aalej/issues-6932

Alternatively, make a directory containing the ff files:

src/index.ts

import { Datastore } from "@google-cloud/datastore";

const datastore = new Datastore({
  projectId: "some-testproject",
});

export async function getNamespaces() {
  const query = datastore.createQuery("__namespace__").select("__key__");
  const [entities] = await datastore.runQuery(query);
  const namespaces = entities.map((entity) => entity[datastore.KEY].name);
  return namespaces;
}

export async function addEntity(namespace: string, kind: string[], data: any) {
  const entityKey = datastore.key({
    path: kind,
    namespace,
  });
  const entity = {
    key: entityKey,
    data,
  };
  await datastore.save(entity);
}

async function main() {
  await addEntity("Tasks", ["Work Tasks"], {
    category: "Personal",
    done: false,
    priority: 4,
    description: "Learn Cloud Datastore",
  });

  const namespaces = await getNamespaces();
  console.log(namespaces);
}

main();

tsconfig.json

{
  "compilerOptions": {
    "target": "es2016",
    "module": "commonjs",
    "esModuleInterop": true,
    "forceConsistentCasingInFileNames": true,
    "strict": true,
    "skipLibCheck": true,
    "outDir": "lib"
  },
  "include": ["src"],
  "exclude": []
}

package.json

{
  "version": "1.0.0",
  "description": "",
  "main": "lib/index.js",
  "scripts": {
    "build": "tsc",
    "build:watch": "tsc --watch"
  },
  "devDependencies": {
    "@google-cloud/datastore": "^8.6.0",
    "typescript": "^5.4.3"
  }
}

[REQUIRED] Steps to reproduce

Testing while connected to the emulator

1. Run npm i
2. Run gcloud emulators firestore start --database-mode=datastore-mode --host-port=127.0.0.1:8081
3. On a separate terminal, run export DATASTORE_EMULATOR_HOST=127.0.0.1:8081
4. Run npm run build
5. Run node . or node lib/index.js

[REQUIRED] Expected behavior

Console logs should show the namespaces on Datastore emulator.

When connecting to production, console logs show the namespaces on Datastore:

[ 'Tasks' ]

Steps to test on a production environment:

1. Run unset DATASTORE_EMULATOR_HOST
2. Run export GOOGLE_APPLICATION_CREDENTIALS=<path_to_service_account_key.json>
3. Run npm run build
4. Run node . or node lib/index.js

[REQUIRED] Actual behavior

When connected to the emulator, console log outputs an empty array

[]