Use wasm modules from artifact

.github/actions/prepare/action.yml

@@ -4,7 +4,6 @@ description: Prepare CI environment
 runs:
   using: composite
   steps:
-    - uses: actions/checkout@v4
     - name: Install Flutter
       uses: subosito/flutter-action@v2
       with:
@@ -20,4 +19,6 @@ runs:
       run: flutter pub global activate melos
     - name: Install dependencies
       shell: sh
+      env:
+        IS_IN_POWERSYNC_CI: 1
       run: melos prepare

.github/workflows/check.yml

@@ -11,11 +11,12 @@ on:
 jobs:
   setup:
     uses: ./.github/workflows/prepare_wasm.yml
-
+  
   build:
     runs-on: ubuntu-latest
     needs: [setup]
     steps:
+      - uses: actions/checkout@v4
       - uses: ./.github/actions/prepare
       - name: Check formatting
         run: melos format:check:packages
@@ -28,6 +29,7 @@ jobs:
     runs-on: ubuntu-latest
     needs: [setup]
     steps:
+      - uses: actions/checkout@v4
       - uses: ./.github/actions/prepare
       - name: Check pana score
         run: |
@@ -38,6 +40,7 @@ jobs:
     runs-on: ubuntu-latest
     needs: [setup]
     steps:
+      - uses: actions/checkout@v4
       - uses: ./.github/actions/prepare
       - name: Run flutter tests
         run: melos test
@@ -48,6 +51,7 @@ jobs:
     runs-on: ubuntu-latest
     needs: [setup]
     steps:
+      - uses: actions/checkout@v4
       - uses: ./.github/actions/prepare
       - name: Check formatting
         run: melos format:check:demos

.github/workflows/prepare_wasm.yml

@@ -14,7 +14,7 @@ jobs:
         id: cache_build
         with:
           path: packages/sqlite3_wasm_build/dist/
-          key: ${{ runner.os }}-${{ hashFiles('packages/sqlite3_wasm_build/build.sh') }}
+          key: wasm-${{ runner.os }}-${{ hashFiles('packages/sqlite3_wasm_build/build.sh') }}
 
       - name: Setup Homebrew
         if: steps.cache_build.outputs.cache-hit != 'true'

packages/powersync_core/lib/src/setup_web.dart

@@ -4,6 +4,7 @@ import 'package:collection/collection.dart';
 import 'package:pub_semver/pub_semver.dart';
 import 'package:pubspec_parse/pubspec_parse.dart';
 import 'package:args/args.dart';
+import 'package:path/path.dart' as p;
 
 Future<void> downloadWebAssets(List<String> arguments,
     {bool encryption = false}) async {
@@ -46,6 +47,11 @@ Future<void> downloadWebAssets(List<String> arguments,
     exit(1);
   }
 
+  if (Platform.environment.containsKey('IS_IN_POWERSYNC_CI')) {
+    print('IS_IN_POWERSYNC_CI env variable is set, copying from local build');
+    return _copyPrecompiled(Directory.current, wasmFileName);
+  }
+
   try {
     final httpClient = HttpClient();
 
@@ -177,3 +183,25 @@ Future<void> downloadFile(
         'Failed to download file: ${response.statusCode} ${response.reasonPhrase}');
   }
 }
+
+Future<void> _copyPrecompiled(Directory project, String wasmFile) async {
+  // Keep going up until we see the melos.yaml file indicating the workspace
+  // root.
+  var dir = project;
+  while (!await File(p.join(dir.path, 'melos.yaml')).exists()) {
+    print('Looking for melos workspace in $dir');
+    final parent = dir.parent;
+    if (p.equals(parent.path, dir.path)) {
+      throw 'Melos workspace not found';
+    }
+
+    dir = parent;
+  }
+
+  // In the CI, an earlier step will have put these files into the prepared
+  // sqlite3_wasm_build package.
+  final destination = p.join(project.path, 'web');
+  final wasmSource = p.join(dir.path, 'packages', 'sqlite3_wasm_build', 'dist');
+  print('Copying $wasmFile from $wasmSource to $destination');
+  await File(p.join(wasmSource, wasmFile)).copy(p.join(destination, wasmFile));
+}

packages/powersync_core/pubspec.yaml

@@ -28,6 +28,7 @@ dependencies:
   args: ^2.6.0
   pub_semver: ^2.0.0
   pubspec_parse: ^1.3.0
+  path: ^1.8.0
 
 dev_dependencies:
   lints: ^5.1.1
@@ -37,7 +38,6 @@ dev_dependencies:
   shelf_router: ^1.1.4
   shelf_static: ^1.1.2
   stream_channel: ^2.1.2
-  path: ^1.8.3
 
 platforms:
   android: