Tuesday, September 16, 2014

Docker images for Dart now available

Developers increasingly want to use the same language and business logic on the client and the server to reduce risk and complexity. To help developers easily build and deploy end-to-end Dart apps, we are happy to announce ready-to-use Docker images for Dart. This expands our Docker usage further beyond the recently announced Docker support in Google App Engine. There are now three Dart-related images on hub.docker.com for you to use: dart, dart-runtime and dart-hello, which uses the same naming scheme as the corresponding Node, Python and Go images already offered.

The image google/dart adds the Dart SDK to google/debian Debian wheezy image. Running Dart in a container is now as simple as this:

  $ docker run -i -t google/dart /usr/bin/dart --version

The image google/dart-runtime inherits from google/dart, and provides a convenient way to run a Dart server application using a one line Dockerfile. To inherit from google/dart-runtime, your server application requires the following layout:

  • has a the pubspec.yaml and pubspec.lock files listing its dependencies.
  • has a file bin/server.dart as the entrypoint script.
  • listens on port 8080

With this layout and a Dockerfile with the following content:

FROM google/dart-runtime

You can run your app in a container as simple as this:

  $ docker build -t my-app .
  $ docker run -d -p 8080:8080 my-app

The last image google/dart-hello is a sample Dart server application, that inherits from dart/runtime. Here is an example of how to run the sample:

  $ docker run -d -p 8080:8080 google/dart-hello

Depending on your local Docker installation the address of the server differs. If you are using boot2docker with the default configuration you can talk to the Dart server in the docker container on http://192.168.59.103:8080:

  $ curl http://192.168.59.103:8080/version

You can choose specific version tags, such as 1.6.0 (recommended), or choose the ‘latest’ tag for the latest stable version. Here is an example of running Dart 1.6 with Docker:

  $ docker run -i -t google/dart:1.6.0 /usr/bin/dart --version

If you haven't already, go and install boot2docker and start building you Dart server application using Docker images. Pushing these images to you server will simplify deployment and ensure you are running the same code on your server as you have been testing locally.

Cross-posted to Google Developers Blog.

By Søren Gjesse, Software Engineer on Dart