Cider

Cider is a framework for implementing continuous integration servers.

Overview

Cider is a set of Meeko agents that can be used to implement a simple continuous integration (CI) server.

Cider itself contains:

• the build slave agent, and
• the build trigger agent.

Meeko itself acts as the build master component.

Right now there is no component that handles the build output, this must be implemented in some other agent. This is actually not that critical as it may seem, check the Tips and Tricks section.

The Build Slave Agent

The first and the most important component that is included is the build slave agent. It exports certain methods over the Meeko RPC service. These methods can be then called by other agents to trigger builds on the relevant build slaves.

Every build slave is associated with a set of labels and a set of runners. The labels are just some user-defined strings that represent the environment of the build slave. It can be e.g. linux-ubuntu-14.04 or macosx-10.9. The set of runners is generated when the slave is started and it describes what script executors are available on the target system. The available runners are:

• bash - bash
• node - node
• powershell - PowerShell.exe
• cmd - cmd.exe

The slave automatically activates the runners that can be found in PATH.

Once the labels and runners are known, the build slave connects to the Meeko RPC service and it exports methods schematically looking like cider.LABEL.RUNNER. The slave just does a Cartesian product, so the number of methods exported is |labels| * |runners|.

Certain information must be supplied as the method arguments:

Name	Type	Description
repository	string	Meeko-compatible repository URL
script	string	the relative path of the script to be executed
env	[]string	the list of environment variables to be defined for the script

The build slave then clones/pulls the specified repository and uses the relevant runner to run the specified script. The variables defined in env are exported for the build script. The build output is being streamed back to the requested using the RPC service. Once the build is finished, the following value is returned

Name	Type	Description
pullDuration	time.Duration	time spent pulling the repository
buildDuration	time.Duration	time spent running the script
error	string	error message, if any

The return code is 0 on success, 1 on failure.

The Build Trigger Agent

The second agent, available as cider build subcommand, can be used to trigger builds remotely. The usage is explained in the example repository.

Installation

You will need Go 1.1 or higher.

Usage

The help output of the cider command is rather verbose, so the best thing to do is to run cider -h.

Example

See the example repository.

Benchmarks

See the benchmark subdirectory for more details.

Discussion

You can join the mailing list.

Status

This is very very much still in development, use at your own risk.

Tips and Tricks

Cider can be used to simply add build slaves to other CI servers. All that is necessary is to run cider build from within the other CI server. That will stream the build output to the console and the other CI server will take care of saving of the build output. This is very handy in case you fancy certain CI server solution, but you need a build slave environment that is not supported. This happens quite often with the hosted CI solutions. Usually only Linux build slaves are supported.

Contributing

See CONTRIBUTING.md.

License

MIT, see the LICENSE file.

About the Original Authors

tchap started with this project because he was too fed up with other continuous integration servers.

Cider is going to be used at Salsita.