motherbrain is an orchestration framework for Chef. In the same way that you would use Chef's Knife command to create a single node, you can use motherbrain to create and control an entire application environment.
- Ruby 2.0.0+
- Chef Server 10 or 11, or Hosted Chef
Install motherbrain via RubyGems:
gem install motherbrain
We don't recommend including motherbrain in your Gemfile.
Before using motherbrain, you'll need to create a configuration file with mb configure
:
Enter a Chef API URL:
Enter a Chef API Client:
Enter the path to the client's Chef API Key:
Enter a SSH user:
Enter a SSH password:
Config written to: '~/.mb/config.json'
You can verify that motherbrain is installed correctly and pointing to a Chef
server by running mb plugin list --remote
:
$ mb plugin list --remote
** listing installed and remote plugins...
motherbrain comes with an init
command to help you get started quickly. Let's
pretend we have an app called MyFace, our hot new social network. We'll
be using the myface cookbook for this tutorial:
$ git clone https://github.com/reset/myface-cookbook
$ cd myface
myface$
We'll generate a new plugin for the cookbook we're developing:
myface$ mb plugin init
create bootstrap.json
create motherbrain.rb
motherbrain plugin created.
Take a look at motherbrain.rb and bootstrap.json,
and then bootstrap with:
mb myface bootstrap bootstrap.json
To see all available commands, run:
mb myface help
myface$
That command created a plugin for us, as well as told us about some commands we
can run. Plugins live within cookbooks in a file named motherbrain.rb
. Notice
that each command starts with the name of our plugin. Once we're done
developing our plugin and we upload it to our Chef server, we can run plugins
from any cookbook on our Chef server.
Lets take a look at all of the commands we can run on a plugin:
myface$ mb myface
using myface (1.1.8)
Tasks:
mb myface app [COMMAND] # Myface application
mb myface bootstrap MANIFEST # Bootstrap a manifest of node groups
mb myface help [COMMAND] # Describe subcommands or one specific subcommand
mb myface nodes # List all nodes grouped by Component and Group
mb myface provision MANIFEST # Create a cluster of nodes and add them to a Chef environment
mb myface upgrade # Upgrade an environment to the specified versions
There are a few things plugins can do:
- Bootstrap existing nodes and configure an environment
- Provision nodes from a compute provider, such as Amazon EC2, Vagrant, or Eucalyptus
- List all nodes in an environment, and what they're used for
- Configure/upgrade an environment with cookbook versions, environment attributes, and then run Chef on all affected nodes
- Run plugin commands, which abstract setting environment attributes and running Chef on the nodes
Notice that there's one task in the help output called app
which doesn't map
to any of those bulletpoints. Let's take a look at the plugin our init
command created:
stack_order do
bootstrap 'app::default'
end
component 'app' do
description "Myface application"
versioned
group 'default' do
recipe 'myface::default'
end
end
A plugin consists of a few things:
stack_order
declares the order to bootstrap component groupscomponent
creates a namespace for different parts of your applicationdescription
provides a friendly summary of the componentversioned
denotes that this component is versioned with an environment attributegroup
declares a group of nodesrecipe
defines how we identify nodes in this group
This plugin is enough to get our app running on a single node. Let's try it out.
Edit bootstrap.json
and fill in a hostname to bootstrap:
{
"nodes": [
{
"groups": ["app::default"],
"hosts": ["box1"]
}
]
}
And then we'll bootstrap our plugin to that node:
myface-cookbook$ knife environment create motherbrain_tutorial
myface-cookbook$ mb myface bootstrap bootstrap.json -e motherbrain_tutorial
using myface (0.4.1)
[bootstrap] searching for environment
[bootstrap] Locking chef_environment:motherbrain_tutorial
[bootstrap] performing bootstrap on group(s): ["app::default"]
[bootstrap] Unlocking chef_environment:motherbrain_tutorial
[bootstrap] Success
That's it! But that's not much different from using knife bootstrap
, and it
took a lot more work.
myface-cookbook$ ls recipes/
database.rb default.rb webserver.rb
myface-cookbook$ cat recipes/default.rb
include_recipe "myface::webserver"
include_recipe "myface::database"
We're currently using the default
recipe in our plugin, which ends up adding
both the webserver
and database
recipes to our node's runlist. Let's change
the automatically-generated plugin to better fit the architecture for our
application:
stack_order do
bootstrap 'app::db'
bootstrap 'app::web'
end
component 'app' do
description "Myface application"
versioned
group 'web' do
recipe 'myface::webserver'
end
group 'db' do
recipe 'myface::database'
end
end
Note that we're bootstrapping the nodes in order, and since our web server depends on a database, we'll want to bootstrap the database first.
And then change our bootstrap manifest to bootstrap 2 nodes instead of 1:
{
"nodes": [
{
"groups": ["app::web"],
"hosts": ["box1"]
},
{
"groups": ["app::db"],
"hosts": ["box2"]
}
]
}
And then run the bootstrap again:
myface-cookbook$ mb myface bootstrap bootstrap.json -e motherbrain_tutorial
using myface (0.4.1)
[bootstrap] searching for environment
[bootstrap] Locking chef_environment:motherbrain_tutorial
[bootstrap] performing bootstrap on group(s): ["app::db"]
[bootstrap] performing bootstrap on group(s): ["app::web"]
[bootstrap] Unlocking chef_environment:motherbrain_tutorial
[bootstrap] Success
That's it! We now have our application deployed to 2 nodes.
If your cookbook is written using the "service orchestration" pattern, motherbrain can make your plugin even simpler.
component "app" do
description "Myface Application"
versioned
service "app" do
service_group "app"
service_recipe "myface::service"
service_attribute "myface.app.state"
end
group "app" do
recipe "myface::app"
end
end
To start the service, you would run mb myface service app.app start
.
This would set the myface.app.state
attribute to 'start' and then do
a partial chef run on all nodes that have myface::app
in their
default runlist, using an override runlist of myface::app_service
.
The same command could be used to stop, restart, or change to any
other state that your service recipe supports.
For each service resource in your cookbook, you should use a single
attribute to define the desired state (stopped, started, restarted).
The default that motherbrain will look for is
component_name.service_name.state
(although you can use anything you
like).
This resource should also be in a dedicated recipe that only works with your services.
When running as a server, MB mounts various enpoinds using the Grape library. For convenience, the tool Swagger has also been integrated into MB's REST API.
First, clone the Swagger UI project.
Next, start your MB server. The only requirement here is a properly defined configuration file:
bundle exec bin/mbsrv
Next, open up dist/index.html
in your clone of swagger-ui. In the top menu bar, paste
in your MB server's address (and port) plus swagger_doc.json
and click Explore.
For a local server, running on the default port, the URL would look like "http:https://localhost:26100/swagger_doc.json".
That's all! You should now be able to explore the REST API of MB using Swagger.
- Jamie Winsor ([email protected])
- Jesse Howarth ([email protected])
- Justin Campbell ([email protected])
- Michael Ivey ([email protected])
- Cliff Dickerson ([email protected])
- Andrew Garson ([email protected])
- Kyle Allan ([email protected])
- Josiah Kiehl ([email protected])
- Steve Rude ([email protected])
If you'd like to contribute, please see our contribution guidelines first.