Build Constructs

A build construct generates deployment artifacts (a Dockerfile, a manifest, a deploy script) and runs only during revali build. Everything else, including anything the app needs during development, belongs in a generic construct.

Generic vs build constructs#

Build constructs share one output directory, so give your files distinctive names.

Writing one#

constructs:
  - name: my_deploy
    path: my_deploy.dart
    method: myDeployConstruct
    is_build: true

BuildConstruct is a base class, so your subclass must be base, final or sealed:

import 'package:revali_construct/revali_construct.dart';

BuildConstruct myDeployConstruct([ConstructOptions? options]) {
  return const MyDeployConstruct();
}

final class MyDeployConstruct extends BuildConstruct {
  const MyDeployConstruct();

  @override
  Future<void> preBuild(RevaliBuildContext context, MetaServer server) async {
    // e.g. check that a required CLI is installed
  }

  @override
  BuildDirectory generate(RevaliBuildContext context, MetaServer server) {
    return BuildDirectory(
      files: [
        AnyFile(
          basename: 'deploy',
          extension: 'sh',
          content: 'echo "deploying ${context.mode.name} build"',
        ),
      ],
    );
  }

  @override
  Future<void> postBuild(RevaliBuildContext context, MetaServer server) async {
    // e.g. push the image
  }
}

What revali build does, in order#

1. Generates the server and all generic constructs.
2. If revali.yaml has a build: section, compiles the server to native executables and exposes them as context.compiledExecutables (each with path, targetArch and an optional debugInfoPath).
3. Calls preBuild on every build construct.
4. Calls generate on every build construct and writes the files to .revali/build/.
5. Calls postBuild on every build construct.

preBuild and postBuild default to doing nothing. context.defines holds the --dart-define values passed to revali build.

A failure in one build construct's generate is logged and does not stop the others.