Setup docker-gen on OS X

ch.nine.docker-gen.plist

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
  <key>KeepAlive</key>
  <true/>
  <key>Label</key>
  <string>ch.nine.docker-gen</string>
  <key>ProgramArguments</key>
  <array>
    <string>/usr/local/bin/docker-gen</string>
    <string>-only-published</string>
    <string>-notify</string>
    <string>/usr/local/bin/nginx -s reload</string>
    <string>-watch</string>
    <string>/usr/local/etc/docker-gen.tmpl</string>
    <string>/usr/local/etc/nginx/servers/docker-gen.conf</string>
  </array>
  <key>RunAtLoad</key>
  <true/>
  <key>WorkingDirectory</key>
  <string>/usr/local</string>
  <key>StandardErrorPath</key>
  <string>/usr/local/var/log/docker-gen.log</string>
  <key>StandardOutPath</key>
  <string>/usr/local/var/log/docker-gen.log</string>
</dict>
</plist>

Docker-gen on the Mac.md

How to setup docker-gen on the Mac:

This guide prepares your mac so you can access your docker containers by their docker-compose project name. So if you have a container with the label com.docker.compose.project=myapp running you will be able to access it on the url myapp.docker.

DNS

This guide assumes that you are already have a working dnsmasq setup on your mac. The follwing command resolves to 127.0.0.1:

dig @localhost myapp.dev

Create the file in /etc/resolver/docker with the following content:

nameserver 127.0.0.1

This lets you resolve the tld .docker to 127.0.0.1.

Now add the folloing line to dnsmasq.conf:

address=/docker/127.0.0.1

Automagic Nginx Vhosts

Nginx and Docker must be already installed. If not:

brew cask install docker
brew install nginx

Then install docker-gen:

brew install docker-gen

Docker-gen needs a template to automatically create vhost configurations. Copy this template to your machine:

curl https://gist.githubusercontent.com/neckhair/b9fdacec5d2e8b301ade47e37aac1755/raw/b6ca8c9e7b9e26aec104711513b205b321413a68/docker-gen.tmpl -o /usr/local/etc/docker-gen.tmpl

To run the service automatically in the background copy the service plist file to the following location:

curl https://gist.githubusercontent.com/neckhair/b9fdacec5d2e8b301ade47e37aac1755/raw/b0ffacf149a6ec1c7014ece213a10f3bd3637620/ch.nine.docker-gen.plist -o /Library/LaunchDaemons/ch.nine.docker-gen.plist
sudo launchctl load -w /Library/LaunchDaemons/ch.nine.docker-gen.plist

Ansible

I created an Ansible role to automate the process. You could use this if you want: https://github.com/neckhair/ansible-role-docker-gen/blob/master/tasks/main.yml.

docker-gen.tmpl

{{ range $project, $containers := groupByLabel $ "com.docker.compose.project" }}

{{ $host := replace "_host_.docker" "_host_" $project 1 }}

upstream {{ $host }} {

{{ range $index, $value := $containers }}
    {{ with $address := index $value.Addresses 0 }}
    server localhost:{{ $address.HostPort }};
    {{ end }}
{{ end }}

}

server {
  listen 80;
  root /Users/phil/src/{{ $project }}/public;
  server_name {{ $host }} *.{{ $host }} {{ $host }}.*;

  client_max_body_size 50M;
  error_page 500 502 503 504 /50x.html;

  gzip_types text/plain text/css application/json application/x-javascript
              text/xml application/xml application/xml+rss text/javascript;

  location = /50x.html {
    root html;
  }

  try_files $uri/index.html $uri @{{ $host }};

  location @{{ $host }} {
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_set_header Host $http_host;
    proxy_redirect off;
    proxy_pass http://{{ $host }};
  }
}
{{ end }}

Don't forget to add address=/docker/127.0.0.1 to dnsmasq.conf if you're not using .dev!