feat: getCrudBatch default limit (#381)

Author: stevensJourney

.changeset/perfect-zebras-marry.md

@@ -0,0 +1,7 @@
+---
+'@powersync/common': patch
+'@powersync/web': patch
+'@powersync/react-native': patch
+---
+
+Improved `getCrudBatch` to use a default limit of 100 CRUD entries.

packages/common/src/client/AbstractPowerSyncDatabase.ts

@@ -132,6 +132,8 @@ export const DEFAULT_POWERSYNC_DB_OPTIONS = {
   crudUploadThrottleMs: DEFAULT_CRUD_UPLOAD_THROTTLE_MS
 };
 
+export const DEFAULT_CRUD_BATCH_LIMIT = 100;
+
 /**
  * Requesting nested or recursive locks can block the application in some circumstances.
  * This default lock timeout will act as a failsafe to throw an error if a lock cannot
@@ -492,7 +494,7 @@ export abstract class AbstractPowerSyncDatabase extends BaseObserver<PowerSyncDB
    * data by transaction. One batch may contain data from multiple transactions,
    * and a single transaction may be split over multiple batches.
    */
-  async getCrudBatch(limit: number): Promise<CrudBatch | null> {
+  async getCrudBatch(limit: number = DEFAULT_CRUD_BATCH_LIMIT): Promise<CrudBatch | null> {
     const result = await this.getAll<CrudEntryJSON>(
       `SELECT id, tx_id, data FROM ${PSInternalTable.CRUD} ORDER BY id ASC LIMIT ?`,
       [limit + 1]

packages/web/tests/crud.test.ts

@@ -1,9 +1,9 @@
-import { afterEach, beforeEach, describe, expect, it } from 'vitest';
 import { AbstractPowerSyncDatabase, Column, ColumnType, CrudEntry, Schema, Table, UpdateType } from '@powersync/common';
 import { PowerSyncDatabase } from '@powersync/web';
+import pDefer from 'p-defer';
 import { v4 as uuid } from 'uuid';
+import { afterEach, beforeEach, describe, expect, it } from 'vitest';
 import { generateTestDb } from './utils/testDb';
-import pDefer from 'p-defer';
 
 const testId = '2290de4f-0488-4e50-abed-f8e8eb1d0b42';
 
@@ -311,4 +311,35 @@ describe('CRUD Tests', () => {
     await txPromise;
     expect(await r).toEqual(null);
   });
+
+  it('CRUD Batch Limits', async () => {
+    const initialBatch = await powersync.getCrudBatch();
+    expect(initialBatch, 'Initial CRUD batch should be null').null;
+
+    /**
+     * Create some items. Use Multiple transactions to demonstrate getCrudBatch does not
+     * group by transaction.
+     */
+    for (let i = 0; i < 2; i++) {
+      await powersync.writeTransaction(async (tx) => {
+        for (let j = 0; j < 51; j++) {
+          await tx.execute(`INSERT INTO assets(id, description) VALUES(uuid(), ?)`, [`test-${i}-${j}`]);
+        }
+      });
+    }
+
+    // This should contain CRUD entries for the first and second transaction
+    const smallBatch = await powersync.getCrudBatch(55);
+    expect(smallBatch, 'CRUD items should be present').exist;
+    expect(smallBatch?.crud.length, 'Should only be 55 CRUD items').eq(55);
+    expect(smallBatch?.haveMore, 'There should be more CRUD items pending').true;
+
+    const defaultBatch = await powersync.getCrudBatch();
+    expect(defaultBatch?.crud.length, 'Should use default limit').eq(100);
+    expect(defaultBatch?.haveMore, 'There should be more CRUD items pending').true;
+
+    const maxBatch = await powersync.getCrudBatch(1000);
+    expect(maxBatch?.crud.length, 'Should contain all created CRUD items').eq(102);
+    expect(maxBatch?.haveMore, 'There should not be any more pending CRUD items').false;
+  });
 });