use read lock for read only queries

Author: stevensJourney

packages/powersync-sdk-react-native/package.json

@@ -27,7 +27,7 @@
   },
   "homepage": "https://docs.powersync.co/",
   "peerDependencies": {
-    "@journeyapps/react-native-quick-sqlite": "0.1.0",
+    "@journeyapps/react-native-quick-sqlite": "0.0.0-dev-20231103124824",
     "base-64": "^1.0.0",
     "react": "*",
     "react-native": "*",
@@ -44,7 +44,7 @@
     "async-lock": "^1.4.0"
   },
   "devDependencies": {
-    "@journeyapps/react-native-quick-sqlite": "0.1.0",
+    "@journeyapps/react-native-quick-sqlite": "0.0.0-dev-20231103124824",
     "@types/async-lock": "^1.4.0",
     "react-native": "0.72.4",
     "react": "18.2.0",

packages/powersync-sdk-react-native/src/db/adapters/react-native-quick-sqlite/RNQSDBAdapter.ts

@@ -25,7 +25,11 @@ export class RNQSDBAdapter extends BaseObserver<DBAdapterListener> implements DB
       this.iterateListeners((cb) => cb.tablesUpdated?.(update));
     });
 
-    const topLevelUtils = this.generateDBHelpers({ execute: this.readOnlyExecute });
+    const topLevelUtils = this.generateDBHelpers({
+      // Arrow function binds `this` for use in readOnlyExecute
+      execute: (sql: string, params?: any[]) => this.readOnlyExecute(sql, params)
+    });
+    // Only assigning get helpers
     this.getAll = topLevelUtils.getAll;
     this.getOptional = topLevelUtils.getOptional;
     this.get = topLevelUtils.get;
@@ -56,13 +60,13 @@ export class RNQSDBAdapter extends BaseObserver<DBAdapterListener> implements DB
   }
 
   /**
-   * This provides a top-level read only execute method which is executed inside a read lock.
+   * This provides a top-level read only execute method which is executed inside a read-lock.
    * This is necessary since the high level `execute` method uses a write-lock under
    * the hood. Helper methods such as `get`, `getAll` and `getOptional` are read only,
    * and should use this method.
    */
   private readOnlyExecute(sql: string, params?: any[]) {
-    return this.readLock(ctx => ctx.execute(sql, params));
+    return this.baseDB.readLock((ctx) => ctx.execute(sql, params));
   }
 
   /**
@@ -78,23 +82,23 @@ export class RNQSDBAdapter extends BaseObserver<DBAdapterListener> implements DB
       /**
        *  Execute a read-only query and return results
        */
-      async getAll<T>(sql: string, parameters?: any[]): Promise<T[]> {
+      getAll: async <T>(sql: string, parameters?: any[]): Promise<T[]> => {
         const res = await tx.execute(sql, parameters);
         return res.rows?._array ?? [];
       },
 
       /**
        * Execute a read-only query and return the first result, or null if the ResultSet is empty.
        */
-      async getOptional<T>(sql: string, parameters?: any[]): Promise<T | null> {
+      getOptional: async <T>(sql: string, parameters?: any[]): Promise<T | null> => {
         const res = await tx.execute(sql, parameters);
         return res.rows?.item(0) ?? null;
       },
 
       /**
        * Execute a read-only query and return the first result, error if the ResultSet is empty.
        */
-      async get<T>(sql: string, parameters?: any[]): Promise<T> {
+      get: async <T>(sql: string, parameters?: any[]): Promise<T> => {
         const res = await tx.execute(sql, parameters);
         const first = res.rows?.item(0);
         if (!first) {