build function

Future<void> build(List<String> arguments, Future<void> builder(BuildConfig config, BuildOutput output))

Runs a native assets build.

Can build native assets which are not already available, or expose existing files. Each individual asset is assigned a unique asset ID.

Example using package:native_toolchain_c:

import 'package:logging/logging.dart';
import 'package:native_assets_cli/native_assets_cli.dart';
import 'package:native_toolchain_c/native_toolchain_c.dart';

void main(List<String> args) async {
  await build(args, (config, output) async {
    final packageName = config.packageName;
    final cbuilder = CBuilder.library(
      name: packageName,
      assetName: '$packageName.dart',
      sources: [
        'src/$packageName.c',
      ],
    );
    await cbuilder.run(
      buildConfig: config,
      buildOutput: output,
      logger: Logger('')
        ..level = Level.ALL
        ..onRecord.listen((record) => print(record.message)),
    );
  });
}

Example outputting assets manually:

import 'dart:io';

import 'package:native_assets_cli/native_assets_cli.dart';

const assetName = 'asset.txt';
final packageAssetPath = Uri.file('data/$assetName');

void main(List<String> args) async {
  await build(args, (config, output) async {
    if (config.linkModePreference == LinkModePreference.static) {
      // Simulate that this hook only supports dynamic libraries.
      throw UnsupportedError(
        'LinkModePreference.static is not supported.',
      );
    }

    final packageName = config.packageName;
    final assetPath = config.outputDirectory.resolve(assetName);
    final assetSourcePath = config.packageRoot.resolveUri(packageAssetPath);
    if (!config.dryRun) {
      // Insert code that downloads or builds the asset to `assetPath`.
      await File.fromUri(assetSourcePath).copy(assetPath.toFilePath());

      output.addDependencies([
        assetSourcePath,
      ]);
    }

    output.addAsset(
      // TODO: Change to DataAsset once the Dart/Flutter SDK can consume it.
      NativeCodeAsset(
        package: packageName,
        name: 'asset.txt',
        file: assetPath,
        linkMode: DynamicLoadingBundled(),
        os: config.targetOS,
        architecture: config.targetArchitecture,
      ),
    );
  });
}

Implementation

Future<void> build(
  List<String> arguments,
  Future<void> Function(BuildConfig config, BuildOutput output) builder,
) async {
  final config = BuildConfigImpl.fromArguments(arguments);
  final output = HookOutputImpl();
  await builder(config, output);
  await output.writeToFile(config: config);
}