Executor Base

Base class defining the interface for executor implementations

An executor is an engine that is capable of running a set of docker containers together.

i.e. Jenkins, Kubernetes, ECS, Mesos

The intention of an executor is to run the launch script defined in the screwdriver job-tools docker container, which is mounted to a container defined by a screwdriver task

This means:

1. Mounting the job-tools container as a volume to $MOUNT_POINT on another container
2. Running the launch script as the entry point to the task container

SD_TOKEN=${token} $MOUNT_POINT/launch --api-uri ${api_uri} ${build_id}

Usage

npm install screwdriver-executor-base

Interface

Start

Required Parameters

Parameter	Type	Description
config	Object	Configuration Object
config.annotations	Object	Optional key/value object
config.apiUri	String	Screwdriver's API
config.buildId	String	The unique ID for a build
config.container	String	Container for the build to run in
config.token	String	Temporary JWT which Executor must exchange with API to get JWT which can act on behalf of the build

Expected Outcome

The start function is expected to create a task in the execution engine.

Expected Return

A Promise that resolves if the task is created correctly, or rejects if it fails.

Stop

Required Parameters

Parameter	Type	Description
config	Object	Configuration Object
config.buildId	String	The unique ID for a build

Expected Outcome

The stop function is expected to stop/cleanup a task in the execution engine.

Expected Return

A Promise that resolves if the task is cleaned up correctly, or rejects if it fails.

Verify

Required Parameters

Parameter	Type	Description
config	Object	Configuration Object
config.annotations	Object	Optional key/value object
config.apiUri	String	Screwdriver's API
config.buildId	String	The unique ID for a build
config.container	String	Container for the build to run in
config.token	String	Temporary JWT which Executor must exchange with API to get JWT which can act on behalf of the build

Expected Outcome

The verify function is expected to check the pods health and status.

Expected Return

A Promise that resolves and returns the message for pod health error or success.

Status

Required Parameters

Parameter	Type	Description
config	Object	Configuration Object
config.buildId	String	The unique ID for a build

Expected Outcome

The status function is expected to get a human readable status of a task in the execution engine.

Expected Return

A Promise that resolves with the current build status, or rejects if it fails.

Stats

Expected Outcome

The stats function is expected to return an object of statistics

Status

Required Parameters

Parameter	Type	Description
config	Object	Configuration Object
config.token	String	Temporary JWT for a build
buildTimeout	Number	Build timeout in minutes

Expected Outcome

The exchangeTokenForBuild function will call API to exchange temporary build JWT with actual build JWT.

Expected Return

A Promise which resolves to actual build JWT

CleanUp

Expected Outcome

The cleanUp function is expected to handle any housekeeping operations like closing connections, queues during the SIGTERM event. Default is no-op

Expected Return

A Promise that resolves or rejects.

StartTimer

Required Parameters

Parameter	Type	Description
config	Object	Configuration Object
config.annotations	Object	Optional key/value object
config.buildStatus	String	The status of the build
config.buildId	String	The unique ID for a build
config.startTime	String	ISO start time of the build
config.jobId	String	job id of the build

Expected Outcome

The StartTimer function is expected to add buildId as key and timeout config value to timeout queue Default is no-op

Expected Return

A Promise that resolves or rejects.

StopTimer

Required Parameters

Parameter	Type	Description
config	Object	Configuration Object
config.buildId	String	The unique ID for a build

Expected Outcome

The StopTimer function is expected to remove key/value buildId from timeout queue Default is no-op

Expected Return

A Promise that resolves or rejects.

Extending

To make use of the validation function for start and stop, you need to override the _start , _stop and _cleanUp methods.

class MyExecutor extends Executor {
    // Implement the interface
    _start(config) {
        if (config.buildId) {
            return this.exchangeTokenForBuild(config.token, buildTimeout).then(buildToken => {
                // do stuff here...
                return Promise.resolve(null);
            });
        }

        return Promise.reject(new Error('Error starting executor'));
    }
}

const executor = new MyExecutor({});
executor.start({
    buildId: '4b8d9b530d2e5e297b4f470d5b0a6e1310d29c5e',
    container: 'node:4',
    apiUri: 'http://localhost:8080',
    token: 'abcdefg'
}, (err) => {
    // do something...
});

Testing

npm test

License

Code licensed under the BSD 3-Clause license. See LICENSE file for terms.