sns-simulator

A library for testing AWS Lambda flows through SNS topics. A very quick project, so there is more that it doesn't do than it does - right now it only supports Lambdas, SNS.createTopic(), SNS.publish() and SNS.subscribe().

There's no reason why this couldn't also hit HTTP/HTTPS endpoints and the like, but that functionality is not built in yet.

How to use it

var SNSSimulator = require('sns-simulator');

Methods

setup()

Stub out methods on aws-sdk to allow you to simulate an SNS flow. After this you can use SNS.createTopic(), SNS.publish() and SNS.subscribe() and it'll use the mocked flow.

Note, though, that no other methods, like SNS.listTopics() are stubbed yet.

In addition to these overrides, there are some extra methods:

registerLambda(arn, func)

Register a lambda function at the fake ARN you specify. func needs to be the function itself, not the module.

reset()

Remove all the topics and lambdas you've created so far.

restore()

Remove the stub from aws-sdk and restore it to regular functionality.

Events

Even though there is no built in functionality for different protocols, SNSSimulator will emit a publish:${arn} event when publishing, as well as a subscribe event when receiving a new subscriber.

Status

So far I've used this in a limited capacity in one project. Which is to say, it is not very widely used or tested. You may run into problems using it - open an issue if you do.