prevent database is locked errors

Author: stevensJourney

.changeset/friendly-queens-invite.md

@@ -0,0 +1,5 @@
+---
+'@powersync/node': patch
+---
+
+[`node:sqlite`] Prevent `database is locked` errors when instantiating the database.

packages/node/src/db/WorkerConnectionPool.ts

@@ -1,24 +1,24 @@
+import * as Comlink from 'comlink';
 import fs from 'node:fs/promises';
 import * as path from 'node:path';
 import { Worker } from 'node:worker_threads';
-import * as Comlink from 'comlink';
 
 import {
   BaseObserver,
   BatchedUpdateNotification,
   DBAdapter,
   DBAdapterListener,
-  LockContext,
-  Transaction,
   DBLockOptions,
-  QueryResult
+  LockContext,
+  QueryResult,
+  Transaction
 } from '@powersync/common';
 import { Remote } from 'comlink';
 import { AsyncResource } from 'node:async_hooks';
+import { isBundledToCommonJs } from '../utils/modules.js';
 import { AsyncDatabase, AsyncDatabaseOpener } from './AsyncDatabase.js';
 import { RemoteConnection } from './RemoteConnection.js';
 import { NodeDatabaseImplementation, NodeSQLOpenOptions } from './options.js';
-import { isBundledToCommonJs } from '../utils/modules.js';
 
 export type BetterSQLite3LockContext = LockContext & {
   executeBatch(query: string, params?: any[][]): Promise<QueryResult>;
@@ -135,10 +135,12 @@ export class WorkerConnectionPool extends BaseObserver<DBAdapterListener> implem
       if (this.options.initializeConnection) {
         await this.options.initializeConnection(connection, isWriter);
       }
-
-      await connection.execute('pragma journal_mode = WAL');
       if (!isWriter) {
         await connection.execute('pragma query_only = true');
+      } else {
+        // We only need to enable this on the writer connection.
+        // We can get `database is locked` errors if we enable this on concurrently opening read connections.
+        await connection.execute('pragma journal_mode = WAL');
       }
 
       return connection;

packages/node/tests/PowerSyncDatabase.test.ts

@@ -1,11 +1,12 @@
 import * as path from 'node:path';
 import { Worker } from 'node:worker_threads';
 
-import { vi, expect, test } from 'vitest';
-import { AppSchema, databaseTest, tempDirectoryTest } from './utils';
+import { LockContext } from '@powersync/common';
+import { randomUUID } from 'node:crypto';
+import { expect, test, vi } from 'vitest';
 import { CrudEntry, CrudTransaction, PowerSyncDatabase } from '../lib';
 import { WorkerOpener } from '../lib/db/options';
-import { LockContext } from '@powersync/common';
+import { AppSchema, databaseTest, tempDirectoryTest } from './utils';
 
 test('validates options', async () => {
   await expect(async () => {
@@ -203,3 +204,22 @@ databaseTest('getCrudTransactions', async ({ database }) => {
   const remainingTransaction = await database.getNextCrudTransaction();
   expect(remainingTransaction?.crud).toHaveLength(15);
 });
+
+tempDirectoryTest('should not present database is locked errors on startup', async ({ tmpdir }) => {
+  for (let i = 0; i < 10; i++) {
+    const database = new PowerSyncDatabase({
+      schema: AppSchema,
+      database: {
+        dbFilename: `${randomUUID()}.sqlite`,
+        dbLocation: tmpdir,
+        implementation: {
+          type: 'node:sqlite'
+        }
+      }
+    });
+
+    // This should not throw
+    await database.waitForReady();
+    await database.close();
+  }
+});

pnpm-workspace.yaml

@@ -3,3 +3,26 @@ packages:
   - packages/*
   - tools/*
   - docs/
+
+ignoredBuiltDependencies:
+  - '@journeyapps/wa-sqlite'
+  - '@parcel/watcher'
+  - '@swc/core'
+  - core-js
+  - core-js-pure
+  - detox
+  - dtrace-provider
+  - electron
+  - electron-winstaller
+  - esbuild
+  - lmdb
+  - lzma-native
+  - msgpackr-extract
+  - react-native-elements
+  - supabase
+  - unrs-resolver
+  - vue-demi
+
+onlyBuiltDependencies:
+  - better-sqlite3
+  - better-sqlite3-multiple-ciphers