MondoKit GCP Datastore

Use Google Cloud Datastore (or Firestore in Datastore Mode) as your app db including DataLoader.

Note: @mondokit libs all require ESM. If your project still uses CommonJS, then you can continue using our previous incarnation, gae-js, until you can make the upgrade.

Find the source code at gcp-datastore on GitHub.


npm install @mondokit/gcp-datastore



Initialise Datastore to be accessed elsewhere in your app.

// On app startup

// Anywhere else in your app
const datastore = datastoreProvider.get();
const key = datastore.key(["MyItem", "id123"]);
const [doc] = await datastore.get(key);


Dataloader implementation to help batch and cache db requests. Used internally by DatastoreRepository

// Apply middleware to create a new dataloader on each request


Access your collections through typed repositories.

Step 1: Define your entity

// Define your class schema
const demoItemSchema = t.type({
  id: t.string,
  name: t.string,

// Define your class type
type DemoItem = t.TypeOf<typeof demoItemSchema>;

// Initialise repository for the collection we want to access data in
const repositoryDirect = new DatastoreRepository<DemoItem>("demo-items", {validator: demoItemSchema });

// OR define a custom class first
class DemoItemRepository extends DatastoreRepository<DemoItem> {
  constructor() {
    super("demo-items", { validator: demoItemSchema });
const repository = new DemoItemsRepository();

// Save an item
await{ id: "id123", name: "test item" });

// Get an item
const item = await repository.get("id123");

// Query items
const list = await demoItemsRepository.query();

// Reindex (re-save) all items in batches (200 by default)
const totalCount1 = await repository.reindexInBatches();
const totalCount2 = await repository.reindexInBatches({ batchSize: 1000 });

// Reindex (re-save) all items in batches with "quiet" mode (no logs written)
const totalCount3 = await repository.reindexInBatches({ quiet: true });

// Reindex (re-save) all items in batches, with a transformation per item
const totalCount4 = await repository.reindexInBatches({ transform: ({id, name}) => ({ id, name: `UPDATED ${name}` })});

// Reindex (re-save) all items at once (WARNING: Small datasets only)
const items1 = await repository.reindex();

// Reindex (re-save) all items at once (WARNING: Small datasets only), with a transformation per item (WARNING: Small datasets only)
const items2 = await repository.reindex(({id, name}) => ({ id, name: `UPDATED ${name}` }));