aws-swf provides high-level classes to build Amazon Simple Workflows using Node.js.
It is built on top of the official Node.js aws-sdk for low-level API calls. You can find the full API reference here.
- node.js >= 0.8
- An active AWS account with Access Keys
- Basic understanding of AWS SimpleWorkflow concepts
npm install aws-swf
Cf. http://docs.aws.amazon.com/AWSJavaScriptSDK/guide/node-configuring.html#Setting_AWS_Credentials
The AWS SDK is sufficient to register SWF objects, since those are just direct API calls. (You can also register them through the AWS console.)
You can run the following example to register the objects used in the following examples :
Example to register "test-domain", "simple-activity" and "simple-workflow"
An ActivityPoller will wait for new tasks from SWF, and emit an activityTask event. The event receives an instance of ActivityTask, which makes it easier to send the response to SWF.
This example starts an Activity Worker which completes immediatly.
The Decider class will wait for new decision tasks from SWF, and emit a decisionTask event. The event receives an instance of DecisionTask, composed of :
- an EventList instance, to query the state of the workflow
- a DecisionResponse instance, to prepare the decider response with decisions
Simple decider worker example : decision worker, which schedules an activity task, then stop the workflow.
To start a workflow, call the start method on a Workflow instance. This call will return a WorkflowExecution instance, which you can use to signal or terminate a workflow.
- Starting a workflow : start an instance of the simple workflow example.
Sometimes you may want to configure the AWS SDK instance. A possible reason is
to set a specific region for aws-swf. Because Node.js allows multiple
instances of the same package for maximal compatibility among libraries, you
would need to do something similar to:
var AWS = require('./node_modules/aws-swf/node_modules/aws-sdk/lib/aws');Instead, you simlpy need to do:
var AWS = require('aws-swf').AWS;An example use case would be:
var AWS = require('aws-swf').AWS;
AWS.config = new AWS.Config({
region: process.env.AWS_REGION || 'us-west-2',
apiVersions: {
swf: '2012-01-25'
}
});The API documentation is available online at http://neyric.github.io/aws-swf/apidoc/
To rebuild the documentation, install jsdoc, then :
jsdoc lib/*.js README.md -d apidoc
Tests can be executed with Mocha :
$ mocha
To get the coverage, run :
$ ./node_modules/.bin/istanbul cover ./node_modules/mocha/bin/_mocha
Then open coverage/lcov-report/index.html
To send the coverage to coveralls, I run locally (I don't know why travis-ci after-script doesn't work...):
$ NODE_ENV=test ./node_modules/.bin/istanbul cover ./node_modules/mocha/bin/_mocha --report lcovonly -- -R spec && cat ./coverage/lcov.info | COVERALLS_REPO_TOKEN=xxxx ./node_modules/coveralls/bin/coveralls.js && rm -rf ./coverage
- aws-swf-toolkit: Node.js Framework for workflows on Amazon SWF
- aws-swf-activities: A collection of Node.js activity workers for Amazon SWF