google/dart-runtime-base repository overview

⁠NOTE: This image is discontinued.

Please consider using the new Docker Official Images for Dart: https://hub.docker.com/_/dart⁠

⁠google/dart-runtime-base

google/dart-runtime-base⁠ is a docker⁠ base image that makes it easy to dockerize a standard Dart⁠ application which is using local packages.

If you have a Dart application which does not require local packages you might be able to use the base image google/dart-runtime⁠ which is simpler.

Using this image requires that a predefined directory layout is used together with a Dockerfile following a predefined template.

It is based on the google/dart⁠ base image.

If the directory layout described below does not work for your setup a Dockerfile based on the google/dart⁠ base image is probably the way to go.

⁠Usage

The following directory layout is used:

project
  Dockerfile
  app
    bin
      server.dart
    pubspec.yaml
  pkg
    my-package-1
    my-package-2

The top-level directory project contains the Dockerfile and the two directories app and pkg. The app directory contains a Dart application with the main entrypoint in bin/server.dart. The packages referred from app/pubspec.yaml must be either packages on pub.dartlang.org or packages in the pkg directory referred to using a relative path dependency, like this:

name: dart_app
version: 0.1.0
description: Dart application.
dependencies:
  my-package-1:
    path: ../pkg/my-package-1
  my-package-2:
    path: ../pkg/my-package-2

You can also use dependency_overrides like this:

name: dart_app
version: 0.1.0
description: Dart application.
dependencies:
  some-package: any
dependency_overrides:
  my-package-1:
    path: ../pkg/my-package-1
  my-package-2:
    path: ../pkg/my-package-2

Then create a Dockerfile in your Dart application directory with the following content:

FROM google/dart-runtime-base

WORKDIR /project/app

# Add the pubspec.yaml files for each local package.
ADD pkg/my-package-1/pubspec.yaml /project/pkg/my-package-1/
ADD pkg/my-package-2/pubspec.yaml /project/pkg/my-package-2/

# Template for adding the application and local packages.
ADD app/pubspec.* /project/app/
RUN pub get
ADD . /project
RUN pub get --offline

Depending on your local packages you need to change the ADD commands in the section after the comment Add the pubspec.yaml files for each local package. Add an ADD command for each of your local packages. Be careful with adding the terminating / for the ADD commands. The rest of the Dockerfile should just be copied.

To build a docker image tagged with my/app run:

docker build -t my/app .

To run this image in a container (assuming it is a server application listening on port 8080):

docker run -d -p 8080:8080 my/app

⁠Accessing the Observatory

The dart-runtime-base image enables the Observatory⁠ for the Dart VM running in the container. The Observatory is listening on the default port 8181. Just map that port to the host when running the app:

docker run -d -p 8080:8080 -p 8181:8181 my-app

If using boot2docker you can access the Observatory using the docker host network on http://192.168.59.103:8181/⁠ (replacing 192.168.59.103 with what you 'boot2docker ip' says).

⁠Passing VM flags

The dart-runtime-base image can receive options for the Dart VM through the environment variable DART_VM_OPTIONS.

docker run -d -p 8080:8080 \
    --env DART_VM_OPTIONS='--old_gen_heap_size=2048 --verbose-gc' \
    my/app

⁠Using this image with App Engine Managed VMs

If you are using this image with App Engine Managed VMs, the app.yaml file must be alongside the Dockerfile in the project directory.

You can set up Observatory access by adding the following to the app.yaml file:

network:
  forwarded_ports: ["8181"]

You can pass VM flags by adding the following to the app.yaml file:

env_variables:
  DART_VM_OPTIONS: --old_gen_heap_size=2048 --verbose-gc