(WIP)-CLOUD-2069 Adding support for multiple compose files.

Author: Mark Wilson

README.md

@@ -558,6 +558,16 @@ docker_compose { '/tmp/docker-compose.yml':
 
 Give options to the ```docker-compose up``` command, such as ```--remove-orphans```, by using the ```up_args``` option.
 
+To supply multiple overide compose files add the following to the manifest file:
+
+```puppet
+class {'docker::compose':
+  compose_files => ['master-docker-compose.yml', 'override-compose.yml],
+}
+```
+
+Please note you should  supply your master docker-compose file as the first element in the array. As per docker multi compose file support compose files will be merged in the order they are specified in the array.
+
 If you are using a v3.2 compose file or above on a Docker Swarm cluster, use the `docker::stack` class. Include the file resource before you run the stack command.
 
 To deploy the stack, add the following code to the manifest file:

lib/puppet/provider/docker_compose/ruby.rb

@@ -7,23 +7,25 @@
 
   def exists?
     Puppet.info("Checking for compose project #{project}")
-    compose_file = YAML.safe_load(File.read(name))
     compose_services = {}
-    containers = docker([
-                          'ps',
-                          '--format',
-                          "{{.Label \"com.docker.compose.service\"}}-{{.Image}}",
-                          '--filter',
-                          "label=com.docker.compose.project=#{project}",
-                        ]).split("\n")
-    case compose_file['version']
-    when %r{^2(\.[0-3])?$}, %r{^3(\.[0-6])?$}
-      compose_services = compose_file['services']
-    # in compose v1 "version" parameter is not specified
-    when nil
-      compose_services = compose_file
-    else
-      raise(Puppet::Error, "Unsupported docker compose file syntax version \"#{compose_file['version']}\"!")
+    compose_files.each do |file|
+      compose_file = YAML.safe_load(File.read(file))
+      containers = docker([
+                            'ps',
+                            '--format',
+                            "{{.Label \"com.docker.compose.service\"}}-{{.Image}}",
+                            '--filter',
+                            "label=com.docker.compose.project=#{project}",
+                          ]).split("\n")
+      case compose_file['version']
+      when %r{^2(\.[0-3])?$}, %r{^3(\.[0-6])?$}
+        compose_services = compose_services.merge(compose_file['services'])
+      # in compose v1 "version" parameter is not specified
+      when nil
+        compose_services = compose_services.merge(compose_file)
+      else
+        raise(Puppet::Error, "Unsupported docker compose file syntax version \"#{compose_file['version']}\"!")
+      end
     end
 
     if compose_services.count != containers.count
@@ -60,14 +62,17 @@ def get_image(service_name, compose_services)
     image
   end
 
+  # Preappend -f  to each compose file in the array and flatten to pass compose files in args. 
+  compose_files_cmd = compose_files.collect {|x| ['-f', x ] }.flatten
+
   def create
     Puppet.info("Running compose project #{project}")
-    args = ['-f', name, 'up', '-d', '--remove-orphans'].insert(2, resource[:options]).insert(5, resource[:up_args]).compact
+    args = [compose_files_cmd, 'up', '-d', '--remove-orphans'].insert(2, resource[:options]).insert(5, resource[:up_args]).compact
     dockercompose(args)
     return unless resource[:scale]
     instructions = resource[:scale].map { |k, v| "#{k}=#{v}" }
     Puppet.info("Scaling compose project #{project}: #{instructions.join(' ')}")
-    args = ['-f', name, 'scale'].insert(2, resource[:options]).compact + instructions
+    args = [compose_files_cmd, 'scale'].insert(2, resource[:options]).compact + instructions
     dockercompose(args)
   end
 

lib/puppet/type/docker_compose.rb

@@ -7,10 +7,6 @@ def refresh
     provider.restart
   end
 
-  newparam(:name) do
-    desc 'Docker compose file path.'
-  end
-
   newparam(:scale) do
     desc 'A hash of compose services and number of containers.'
     validate do |value|
@@ -38,6 +34,13 @@ def refresh
     end
   end
 
+  newparam(:compose_files, :array_matching => :all) do
+    desc 'An array of Docker Compose Files paths.'
+    validate do |value|
+      raise_('compose files should be an array') unless value.is_a? String
+    end
+  end
+
   autorequire(:file) do
     self[:name]
   end