Cleanup asset download name mapping. Update demos.

stevensJourney · stevensJourney · commit fbb111e855b7 · 2025-10-20T17:07:10.000+02:00
diff --git a/demos/example-electron-node/README.md b/demos/example-electron-node/README.md
@@ -9,8 +9,9 @@ In particular:
    queries. This worker is part of the `@powersync/node` package and wouldn't be copied into the resulting Electron
    app by default. For this reason, this example has its own `src/main/worker.ts` loaded with `new URL('./worker.ts', import.meta.url)`.
 2. In addition to the worker, PowerSync requires access to a SQLite extension providing sync functionality.
-   This file is also part of the `@powersync/node` package and called `powersync.dll`, `libpowersync.dylib` or
-   `libpowersync.so` depending on the operating system.
+   This file is also part of the `@powersync/node` package and is the prebuilt release asset (for example
+   `powersync_x64.dll`, `libpowersync_x64.dylib` or `libpowersync_x64.so`) depending on the operating system and
+   architecture.
    We use the `copy-webpack-plugin` package to make sure a copy of that file is available to the main process,
    and load it in the custom `src/main/worker.ts`.
 3. The `get()` and `getAll()` methods are exposed to the renderer process with an IPC channel.
@@ -21,7 +22,7 @@ To see it in action:
 2. Copy `.env.local.template` to `.env.local`, and complete the environment variables. You can generate a [temporary development token](https://docs.powersync.com/usage/installation/authentication-setup/development-tokens), or leave blank to test with local-only data.
    The example works with the schema from the [PowerSync + Supabase tutorial](https://docs.powersync.com/integration-guides/supabase-+-powersync#supabase-powersync).
 3. `cd` into this directory. In this mono-repo, you'll have to run `./node_modules/.bin/electron-rebuild` once to make sure `@powersync/better-sqlite3` was compiled with Electron's toolchain.
-3. Finally, run `pnpm start`.
+4. Finally, run `pnpm start`.
 
 Apart from the build setup, this example is purposefully kept simple.
 To make sure PowerSync is working, you can run `await powersync.get('SELECT powersync_rs_version()');` in the DevTools
diff --git a/demos/example-electron-node/config.ts b/demos/example-electron-node/config.ts
@@ -1,18 +1,17 @@
-import OS from 'node:os';
 import path from 'node:path';
 
-import type { ForgeConfig } from '@electron-forge/shared-types';
-import { MakerSquirrel } from '@electron-forge/maker-squirrel';
-import { MakerZIP } from '@electron-forge/maker-zip';
 import { MakerDeb } from '@electron-forge/maker-deb';
 import { MakerRpm } from '@electron-forge/maker-rpm';
+import { MakerSquirrel } from '@electron-forge/maker-squirrel';
+import { MakerZIP } from '@electron-forge/maker-zip';
 import { AutoUnpackNativesPlugin } from '@electron-forge/plugin-auto-unpack-natives';
 import { WebpackPlugin } from '@electron-forge/plugin-webpack';
-import { type Configuration, type ModuleOptions, type DefinePlugin } from 'webpack';
+import type { ForgeConfig } from '@electron-forge/shared-types';
+import { getPowerSyncExtensionFilename } from '@powersync/node/worker.js';
+import type ICopyPlugin from 'copy-webpack-plugin';
 import * as dotenv from 'dotenv';
 import type IForkTsCheckerWebpackPlugin from 'fork-ts-checker-webpack-plugin';
-import type ICopyPlugin from 'copy-webpack-plugin';
-
+import { type Configuration, type DefinePlugin, type ModuleOptions } from 'webpack';
 dotenv.config({ path: '.env.local' });
 
 const ForkTsCheckerWebpackPlugin: typeof IForkTsCheckerWebpackPlugin = require('fork-ts-checker-webpack-plugin');
@@ -57,17 +56,7 @@ const defaultWebpackRules: () => Required<ModuleOptions>['rules'] = () => {
   ];
 };
 
-const platform = OS.platform();
-let extensionPath: string;
-if (platform === 'win32') {
-  extensionPath = 'powersync.dll';
-} else if (platform === 'linux') {
-  extensionPath = 'libpowersync.so';
-} else if (platform === 'darwin') {
-  extensionPath = 'libpowersync.dylib';
-} else {
-  throw 'Unknown platform, PowerSync for Node.js currently supports Windows, Linux and macOS.';
-}
+let extensionFilename = getPowerSyncExtensionFilename();
 
 const mainConfig: Configuration = {
   /**
@@ -84,8 +73,8 @@ const mainConfig: Configuration = {
     new CopyPlugin({
       patterns: [
         {
-          from: path.resolve(require.resolve('@powersync/node/package.json'), `../lib/${extensionPath}`),
-          to: path.join('powersync', extensionPath)
+          from: path.resolve(require.resolve('@powersync/node/package.json'), `../lib/${extensionFilename}`),
+          to: path.join('powersync', extensionFilename)
         }
       ]
     }),
diff --git a/demos/example-electron-node/src/main/worker.ts b/demos/example-electron-node/src/main/worker.ts
@@ -1,25 +1,14 @@
-import * as path from 'node:path';
-import OS from 'node:os';
 import Database from 'better-sqlite3';
+import * as path from 'node:path';
 
-import { startPowerSyncWorker } from '@powersync/node/worker.js';
+import { getPowerSyncExtensionFilename, startPowerSyncWorker } from '@powersync/node/worker.js';
 
 function resolvePowerSyncCoreExtension() {
-  const platform = OS.platform();
-  let extensionPath: string;
-  if (platform === 'win32') {
-    extensionPath = 'powersync.dll';
-  } else if (platform === 'linux') {
-    extensionPath = 'libpowersync.so';
-  } else if (platform === 'darwin') {
-    extensionPath = 'libpowersync.dylib';
-  } else {
-    throw 'Unknown platform, PowerSync for Node.js currently supports Windows, Linux and macOS.';
-  }
+  const extensionFilename = getPowerSyncExtensionFilename();
 
   // This example uses copy-webpack-plugin to copy the prebuilt library over. This ensures that it is
   // available in packaged release builds.
-  let libraryPath = path.resolve(__dirname, 'powersync', extensionPath);
+  let libraryPath = path.resolve(__dirname, 'powersync', extensionFilename);
 
   if (__dirname.indexOf('app.asar') != -1) {
     // Our build configuration ensures the extension is always available outside of the archive too.
diff --git a/packages/node/download_core.js b/packages/node/download_core.js
@@ -14,14 +14,7 @@ const versionHashes = {
   'libpowersync_aarch64.dylib': 'bfb4f1ec207b298aff560f1825f8123d24316edaa27b6df3a17dd49466576b92'
 };
 
-// Map of all assets to their destinations
-const assetMap = {
-  'powersync_x64.dll': 'powersync.dll',
-  'libpowersync_x64.so': 'libpowersync.so',
-  'libpowersync_aarch64.so': 'libpowersync-aarch64.so',
-  'libpowersync_x64.dylib': 'libpowersync.dylib',
-  'libpowersync_aarch64.dylib': 'libpowersync-aarch64.dylib'
-};
+const assets = Object.keys(versionHashes);
 
 const hashStream = async (input) => {
   for await (const chunk of input.pipe(createHash('sha256')).setEncoding('hex')) {
@@ -42,14 +35,14 @@ const hashLocal = async (filePath) => {
   }
 };
 
-const downloadAsset = async (asset, destination) => {
-  const destinationPath = path.resolve('lib', destination);
+const downloadAsset = async (asset) => {
+  const destinationPath = path.resolve('lib', asset);
   const expectedHash = versionHashes[asset];
 
   // Check if file exists and has correct hash
   const currentHash = await hashLocal(destinationPath);
   if (currentHash == expectedHash) {
-    console.debug(`${destination} is up-to-date, skipping download`);
+    console.debug(`${asset} is up-to-date, skipping download`);
     return;
   }
 
@@ -68,17 +61,16 @@ const downloadAsset = async (asset, destination) => {
   if (hashAfterDownloading != expectedHash) {
     throw `Unexpected hash after downloading ${asset} (got ${hashAfterDownloading}, expected ${expectedHash})`;
   }
-  console.log(`Successfully downloaded ${destination}`);
+  console.log(`Successfully downloaded ${asset}`);
 };
 
-const checkAsset = async (asset, destination) => {
-  const destinationPath = path.resolve('lib', destination);
+const checkAsset = async (asset) => {
+  const destinationPath = path.resolve('lib', asset);
   const expectedHash = versionHashes[asset];
   const currentHash = await hashLocal(destinationPath);
 
   return {
     asset,
-    destination,
     destinationPath,
     expectedHash,
     currentHash,
@@ -96,9 +88,7 @@ const download = async () => {
 
   // First check all assets
   console.log('Checking existing files...');
-  const checks = await Promise.all(
-    Object.entries(assetMap).map(([asset, destination]) => checkAsset(asset, destination))
-  );
+  const checks = await Promise.all(assets.map((asset) => checkAsset(asset, asset)));
 
   const toDownload = checks.filter((check) => !check.isValid);
   const upToDate = checks.filter((check) => check.isValid);
@@ -107,23 +97,22 @@ const download = async () => {
   if (upToDate.length > 0) {
     console.log('\nUp-to-date files:');
     for (const check of upToDate) {
-      console.log(`  ✓ ${check.destination}`);
+      console.log(`  ✓ ${check.asset}`);
     }
   }
 
   if (toDownload.length > 0) {
     console.log('\nFiles to download:');
     for (const check of toDownload) {
       if (!check.exists) {
-        console.log(`  • ${check.destination} (missing)`);
+        console.log(`  • ${check.asset} (missing)`);
       } else {
-        console.log(`  • ${check.destination} (hash mismatch)`);
+        console.log(`  • ${check.asset} (hash mismatch)`);
       }
     }
 
     console.log('\nStarting downloads...');
-    // Download required assets in parallel
-    await Promise.all(toDownload.map((check) => downloadAsset(check.asset, check.destination)));
+    await Promise.all(toDownload.map((check) => downloadAsset(check.asset)));
 
     console.log('\nAll downloads completed successfully!');
   } else {
diff --git a/packages/node/src/db/SqliteWorker.ts b/packages/node/src/db/SqliteWorker.ts
@@ -22,48 +22,55 @@ export interface PowerSyncWorkerOptions {
   loadBetterSqlite3: () => Promise<any>;
 }
 
+/**
+ * @returns The relevant PowerSync extension binary filename for the current platform and architecture
+ */
+export function getPowerSyncExtensionFilename() {
+  const platform = OS.platform();
+  const arch = OS.arch();
+  let extensionFile: string;
+
+  if (platform == 'win32') {
+    if (arch == 'x64') {
+      extensionFile = 'powersync_x64.dll';
+    } else {
+      throw new Error('Windows platform only supports x64 architecture.');
+    }
+  } else if (platform == 'linux') {
+    if (arch == 'x64') {
+      extensionFile = 'libpowersync_x64.so';
+    } else if (arch == 'arm64') {
+      extensionFile = 'libpowersync_aarch64.so';
+    } else {
+      throw new Error('Linux platform only supports x64 and arm64 architectures.');
+    }
+  } else if (platform == 'darwin') {
+    if (arch == 'x64') {
+      extensionFile = 'libpowersync_x64.dylib';
+    } else if (arch == 'arm64') {
+      extensionFile = 'libpowersync_aarch64.dylib';
+    } else {
+      throw new Error('macOS platform only supports x64 and arm64 architectures.');
+    }
+  } else {
+    throw new Error(
+      `Unknown platform: ${platform}, PowerSync for Node.js currently supports Windows, Linux and macOS.`
+    );
+  }
+
+  return extensionFile;
+}
+
 export function startPowerSyncWorker(options?: Partial<PowerSyncWorkerOptions>) {
   const resolvedOptions: PowerSyncWorkerOptions = {
     extensionPath() {
       const isCommonJsModule = isBundledToCommonJs;
-
-      const platform = OS.platform();
-      const arch = OS.arch();
-      let extensionPath: string;
-
-      if (platform == 'win32') {
-        if (arch == 'x64') {
-          extensionPath = 'powersync.dll';
-        } else {
-          throw new Error('Windows platform only supports x64 architecture.');
-        }
-      } else if (platform == 'linux') {
-        if (arch == 'x64') {
-          extensionPath = 'libpowersync.so';
-        } else if (arch == 'arm64') {
-          extensionPath = 'libpowersync-aarch64.so';
-        } else {
-          throw new Error('Linux platform only supports x64 and arm64 architectures.');
-        }
-      } else if (platform == 'darwin') {
-        if (arch == 'x64') {
-          extensionPath = 'libpowersync.dylib';
-        } else if (arch == 'arm64') {
-          extensionPath = 'libpowersync-aarch64.dylib';
-        } else {
-          throw new Error('macOS platform only supports x64 and arm64 architectures.');
-        }
-      } else {
-        throw new Error(
-          `Unknown platform: ${platform}, PowerSync for Node.js currently supports Windows, Linux and macOS.`
-        );
-      }
-
+      const extensionFilename = getPowerSyncExtensionFilename();
       let resolved: string;
       if (isCommonJsModule) {
-        resolved = path.resolve(__dirname, '../lib/', extensionPath);
+        resolved = path.resolve(__dirname, '../lib/', extensionFilename);
       } else {
-        resolved = url.fileURLToPath(new URL(`../${extensionPath}`, import.meta.url));
+        resolved = url.fileURLToPath(new URL(`../${extensionFilename}`, import.meta.url));
       }
 
       return resolved;
