substor

Node.js promise based utility to subscribe to one or more Redis channels at a time and store all messages received on subscribed channels. Messages can then be inspected.

I use my other npm module messageCheckr with substor to verify JMS / SOAP are correct. substor is used on my work projects to verify integration messages from both UI tests using Cucumber/Protractor and API tests using mocha/supertest.

Compatibility

Works with Node.js v0.12.* and higher

Getting Started

npm install substor to install from the NPM registry.

Install

var substor = require('substor');

Usage

The following example is how I have used substor in an API test using mocha.

In hook.js

before(function () {
  return substor.connect({host: 'redisHost', port: 'redisPort'});
});

In testFile.js

it('should do something', function () {
 
  return substore.subscribeToChannels(['redisChannelName'])
    .then(function(){
      // Do something that results in a message or messages to be placed on Redis channel 'redisChannelName'
    })
    .then(function(){
      return substore.getLatestMessageOnChannel('redisChannelName')
    })
    .then(function(latestMessageOnRedisChannelName){
      // latestMessageOnRedisChannelName is a String
      // Do whatever you want to the message.
      // Once done ensure to unsubscribe from the Redis channel(s)
      return substore.unsubscribeFromAllChannels()
    })
});

Methods

All promises returned from methods are Promises/A+ compliant. Underneath the hood q is used.

connect(options)

Param	Type	Description
options	object	Attributes host - (mandatory) Redis host (e.g. host: '127.0.0.1') port - (mandatory) Redis port (e.g. port: '6379') defaultTimeOutMilliseconds - (optional) an integer to override the default of 700 milliseconds. This value is the wait time before getting a message (or message count) from a subscribed channel. debug - (optional) set to true if you need to see more logs.

Returns Promise.

subscribeToChannels(channels)

Param	Type	Description
channels	Array	An array of Redis channels. Each element is a String, e.g. ['channel1', 'channel2']

Returns Promise.

unsubscribeFromAllChannels()

Returns Promise.

getQueue()

Returns object consisting of all messages received on all channels subscribed to.

getMessageCount(channel)

Param	Type	Description
channel	String	Name of channel

Returns Promise that resolves to the number of messages received on the specified channel since it was subscribed to.

getLatestMessageOnChannel(channel)

Param	Type	Description
channel	String	Name of channel

Returns Promise that resolves to the message (String) last received on the specified channel.

getMessageOnChannel(position, channel)

Param	Type	Description
position	Integer	Position of message received, 1 being the latest
channel	String	Name of channel

Returns Promise that resolves to the the message (String) in position on the specified channel.