This package provides the API for hooks in Dart. Hooks are Dart scripts placed in the hook/ directory of a Dart package, designed to automate tasks for a Dart package.

Currently, the main supported hook is the build hook (hook/build.dart). The build hook is executed during a Dart build and enables you to bundle assets with a Dart package.

The main supported asset type is a code asset, code written in other languages that are compiled into machine code. You can use a build hook to do things such as compile or download code assets, and then call these assets from the Dart code of a package. The CodeAsset API is an extension to this package and is available in package:code_assets.

When compiling C, C++ or Objective-C code from source, consider using package:native_toolchain_c:

import 'package:code_assets/code_assets.dart';
import 'package:hooks/hooks.dart';
import 'package:native_toolchain_c/native_toolchain_c.dart';

final builder = CBuilder.library(
  name: 'sqlite3',
  assetName: 'src/third_party/sqlite3.g.dart',
  sources: ['third_party/sqlite/sqlite3.c'],
);

void main(List<String> args) async {
  await build(args, (input, output) async {
    if (input.config.buildCodeAssets) {
      await builder.run(
        input: input,
        output: output,
        defines: {
          if (input.config.code.targetOS == OS.windows)
            // Ensure symbols are exported in dll.
            'SQLITE_API': '__declspec(dllexport)',
        },
      );
    }
  });
}

See the full example in package:code_assets example/sqlite/.

When bundling precompiled dynamic libraries, use package:code_assets directly:

import 'package:code_assets/code_assets.dart';
import 'package:hooks/hooks.dart';

void main(List<String> args) async {
  await build(args, (input, output) async {
    if (input.config.buildCodeAssets) {
      final packageName = input.packageName;
      final assetPathInPackage = input.packageRoot.resolve('...');
      final assetPathDownload = input.outputDirectoryShared.resolve('...');

      output.assets.code.add(
        CodeAsset(
          package: packageName,
          name: '...',
          linkMode: DynamicLoadingBundled(),
          file: assetPathInPackage,
        ),
      );
    }
  });
}

For more information see dart.dev/tools/hooks.

Documentation

For detailed documentation on debugging and the configuration schema, see the documentation.