Refactor to use dart script to download binaries for demos

Author: mugikhan

melos.yaml

@@ -16,7 +16,7 @@ command:
       noPrivate: true
   publish:
     hooks:
-      pre: sh tool/download_binaries.sh v0.1.8 # Download latest core binaries when publishing
+      pre: dart ./scripts/download_core_binary_demos.dart # Download latest core binaries when publishing
     packageFilters:
       noPrivate: true
 
@@ -25,7 +25,7 @@ scripts:
     description: Download SQLite3 WASM for demos
     run: |
       melos bootstrap && melos prepare:assets && dart ./scripts/compile_webworker.dart && dart ./scripts/init_powersync_core_binary.dart
-      melos prepare:demos
+      dart ./scripts/download_core_binary_demos.dart && melos prepare:demos
 
   prepare:demos:
     description: Download SQLite3 wasm for demos

packages/powersync_flutter_libs/.gitignore

@@ -28,4 +28,7 @@ migrate_working_dir/
 .dart_tool/
 build/
 
-*.a
+!*.so
+*.a
+!*.dylib
+!*.dll

scripts/download_core_binary_demos.dart

@@ -0,0 +1,37 @@
+/// Downloads the powersync-core dynamic library to run the demos using melos
+/// This is only necessary in the monorepo setup
+import 'dart:io';
+
+final coreUrl =
+    'https://github.com/powersync-ja/powersync-sqlite-core/releases/download/v0.1.8';
+
+void main() async {
+  final powersyncLibsLinuxPath = "packages/powersync_flutter_libs/linux";
+  final powersyncLibsWindowsPath = "packages/powersync_flutter_libs/windows";
+
+  final linuxArm64FileName = "libpowersync_aarch64.so";
+  final linuxX64FileName = "libpowersync_x64.so";
+  final windowsX64FileName = "powersync_x64.dll";
+
+  // Download dynamic library
+  await downloadFile("$coreUrl/$linuxArm64FileName",
+      "$powersyncLibsLinuxPath/$linuxArm64FileName");
+  await downloadFile("$coreUrl/$linuxX64FileName",
+      "$powersyncLibsLinuxPath/$linuxX64FileName");
+  await downloadFile("$coreUrl/$windowsX64FileName",
+      "$powersyncLibsWindowsPath/$windowsX64FileName");
+}
+
+Future<void> downloadFile(String url, String savePath) async {
+  print('Downloading: $url');
+  var httpClient = HttpClient();
+  var request = await httpClient.getUrl(Uri.parse(url));
+  var response = await request.close();
+  if (response.statusCode == HttpStatus.ok) {
+    var file = File(savePath);
+    await response.pipe(file.openWrite());
+  } else {
+    print(
+        'Failed to download file: ${response.statusCode} ${response.reasonPhrase}');
+  }
+}