crew

crew makes managing Docker a breeze.

Installation

$ npm install crew

Quick start

First you need to add a reference to crew to to your application.

const crew = require('crew');

To connect to a Docker server, call the crew function and provide the hostname as well as the port. Additionally, you need to provide a private key and a certificate for client-side authentication, and a CA certificate for server-side authentication.

You may use the environment variables DOCKER_HOST and DOCKER_CERT_PATH to get appropriate values.

crew({
  host: url.parse(process.env.DOCKER_HOST).hostname,
  port: url.parse(process.env.DOCKER_HOST).port,
  keys: {
    privateKey: fs.readFileSync(path.join(process.env.DOCKER_CERT_PATH, 'key.pem')),
    certificate: fs.readFileSync(path.join(process.env.DOCKER_CERT_PATH, 'cert.pem')),
    caCertificate: fs.readFileSync(path.join(process.env.DOCKER_CERT_PATH, 'ca.pem'))
  }
}, (err, dockWorker) => {
  // ...
});

Please note that the initially provided options are available at dockWorker.options.

Pinging Docker

To ping the Docker server, use the ping function.

dockWorker.ping(err => {
  // ...
});

Verifying that an image is available

If you need to verify whether an image is available on the Docker server, use the hasImage function and provide the name of the image.

dockWorker.hasImage({ name: 'node' }, (err, hasImage) => {
  console.log(hasImage); // => true
  // ...
});

hasImage also supports tags to check for a particular version of an image, as in the following example.

dockWorker.hasImage({ name: 'node', tag: '4.0' }, (err, hasImage) => {
  console.log(hasImage); // => true
  // ...
});

Downloading an image

To download an image to the Docker server, use the downloadImage function and provide the name of the image.

dockWorker.downloadImage({ name: 'node' }, err => {
  // ...
});

If you want to download a specific version, add the tag to the name of the image.

dockWorker.downloadImage({ name: 'node', tag: '4.0' }, err => {
  // ...
});

If you don't specify a tag, the tag latest will be used which is also the default used by the Docker CLI.

Building an image

To build an image, call the buildImage function and provide the directory you want to use, a Dockerfile, and the name of the image.

dockWorker.buildImage({
  directory: __dirname,
  dockerfile: path.join(__dirname, 'my-dockerfile'),
  name: 'myImage'
}, err => {
  // ...
});

buildImage also supports tags fors images by passing in the optional tag option.

dockWorker.buildImage({
  directory: __dirname,
  dockerfile: path.join(__dirname, 'my-dockerfile'),
  name: 'myImage',
  tag: '0.1.0'
}, err => {
  // ...
});

If you want to exclude some files from the newly built image, you can use the dockerignore property to provide the path to an ignore file.

dockWorker.buildImage({
  directory: __dirname,
  dockerfile: path.join(__dirname, 'my-dockerfile'),
  dockerignore: path.join(__dirname, 'my-dockerignore'),
  name: 'myImage'
}, err => {
  // ...
});

If you want to modify the build context right before the image gets built, register a preBuild hook and do whatever you want to do.

dockWorker.buildImage({
  directory: __dirname,
  dockerfile: path.join(__dirname, 'my-dockerfile'),
  dockerignore: path.join(__dirname, 'my-dockerignore'),
  preBuild: (preBuildOptions, done) => {
    console.log(preBuildOptions);
    // => {
    //      directory: '...'
    //    }

    done(null);
  },
  name: 'myImage'
}, err => {
  // ...
});

Starting a container

To create and start a container, call the startContainer function and provide the name of the image and the desired container name. This returns the newly created container's id.

dockWorker.startContainer({
  image: 'node',
  name: 'myContainer'
}, (err, id) => {
  console.log(id); // => '70073a08b0f7fdfef44ca6fe03ba5e796d4773d9628b6f68eb7e34568dc73e1f'
  // ...
});

startContainer also supports image tags.

dockWorker.startContainer({
  image: 'node',
  tag: '4.0',
  name: 'myContainer'
}, (err, id) => {
  console.log(id); // => '70073a08b0f7fdfef44ca6fe03ba5e796d4773d9628b6f68eb7e34568dc73e1f'
  // ...
});

Restarting crashed containers

If you want your container to restart automatically on crashes, add the restart property to the parameter object and set it to true.

dockWorker.startContainer({
  image: 'node',
  name: 'myContainer',
  restart: true
}, (err, id) => {
  // ...
});

Forwarding ports

To forward container ports to the host, add the ports property to the parameter object and hand over an array of forwardings.

dockWorker.startContainer({
  image: 'node',
  name: 'myContainer',
  ports: [
    { container: 3000, host: 80 }
  ]
}, (err, id) => {
  // ...
});

Setting environment variables

To set environment variables, add the env property to the parameter object and hand over the keys and values you want to use as environment variables.

dockWorker.startContainer({
  image: 'node',
  name: 'myContainer',
  env: {
    port: 3000
  }
}, (err, id) => {
  // ...
});

Using volumes

To use volumes from the host, add the volumes property to the parameter object and hand over an array of volume mappings.

dockWorker.startContainer({
  image: 'node',
  name: 'myContainer',
  volumes: [
    { container: '/data', host: '/home/janedoe/foo' }
  ]
}, (err, id) => {
  // ...
});

Using links

To link a container to another one, add the links property to the parameter object and hand over an array of link mappings.

dockWorker.startContainer({
  image: 'node',
  name: 'myContainer',
  links: [
    { name: 'mongodb', alias: 'db' }
  ]
}, (err, id) => {
  // ...
});

Configuring network settings

To add extra hosts to the container's /etc/hosts file, add the network property to the parameter object and assign a hosts property to it.

dockWorker.startContainer({
  image: 'node',
  name: 'myContainer',
  network: {
    hosts: [
      { name: 'example.com', ip: '192.168.0.1' }
    ]
  }
}, (err, id) => {
  // ...
});

Getting information on running containers

To get information on running containers for a specific image, use the getRunningContainersFor function and provide the image name.

dockWorker.getRunningContainersFor({ name: 'node' }, (err, containers) => {
  console.log(containers);
  // => [
  //      {
  //        image: 'node',
  //        name: 'my-container',
  //        ports: [
  //          { container: 3000, host: 3000 }
  //        ],
  //        env: {
  //          PORT: '3000'
  //        },
  //        volumes: [
  //          { container: '/data', host: '/home/janedoe/foo' }
  //        ],
  //        links: [
  //          { name: 'your-container', alias: 'yours' }
  //        ],
  //        network: {
  //          hosts: [
  //            { name: 'example.com', ip: '192.168.0.1' }
  //          ]
  //        }
  //      }
  //    ]
});

Again, you may also specify an image tag.

dockWorker.getRunningContainersFor({ name: 'node', tag: '4.0' }, (err, containers) => {
  // ...
});

Alternatively you may specify the image name by a regular expression.

dockWorker.getRunningContainersFor(/^no/, (err, containers) => {
  // ...
});

Getting logs of a container

To get the logs of a running container, call the getLogs function and provide the name of the container.

dockWorker.getLogs('myContainer', (err, stdOut, stdErr) => {
  // ...
});

Stopping a container

To stop and automatically remove a running container, call the stopContainer function and provide the name of the container.

dockWorker.stopContainer('myContainer', err => {
  // ...
});

Running the build

This module can be built using Grunt. Besides running the tests, this also analyses the code. To run Grunt, go to the folder where you have installed crew and run grunt. You need to have grunt-cli installed.

$ grunt

If you're using Docker Machine, make sure to copy the crew source folder to your Docker Machine before running the tests. Assuming your Docker machine name is dev and you're in the crew source folder on your local machine run the following commands.

docker-machine ssh dev -- mkdir -p $(pwd)
docker-machine scp -r . dev:$(pwd)

After this, you can run the tests as described above.

License

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

thenativeweb/crew