freeloader

Just a super easy load-testing framework.

- no complex GUI to get lost in
- load tests == code, and yes you should check them in :)
- easy to plug-in to your CI server
- get started in seconds


Getting started

Freeloader uses 4 basic keywords:

- request to create an HTTP request using unirest
- emit to push the request down the pipeline
- send to make the actual HTTP call
- join to join 2 streams together

The simplest test looks like:

``js
require('freeloader').global();

// See unirest documentation for all the options (headers, file uploads...)
var r = request.get('http://localhost:3000/people')
.header('Accept', 'application/json');

emit(r).pipe(send());
`

That's it! This test sends a single HTTP request, and finishes as soon as the response is received.

Building a pipeline

It becomes a lot more interesting when we start building a pipeline. Each step in the pipeline has access to all requests & responses. They can modify payloads, generate more requests, or collect data for reporting.

freeloader-bundle contains a lot of useful modules to get started. Each module is an instance of a Node.js stream, and you can also easily create your own.

`js
require('freeloader-bundle').global();

emit(r)
.pipe(stopTimer('30s'))
.pipe(concurrent(50))
.pipe(transform(randomData))
.pipe(progressDots())
.pipe(consoleSummary())
.pipe(responseTimeGraph('./graph.jpg'))
.pipe(send())
`

Which outputs something like:

`bash
............................................................
....................................................

Waiting for pending requests to finish...

Response count = 112

Response times
Min = 16ms
Max = 182ms
Mean = 66ms
Median = 58ms
75th percentile = 82ms
95th percentile = 150ms
`

The test suite will end:

- when every request has been sent
- or when you press Ctrl-C
- or when a module adds its own stopping condition

Test pipelines can easily be included in a CI test suite:

`js
it('generates load test reports', function(done) {
emit(r1)
.pipe(times(50))
.pipe(jsonSummary('./report.json'))
.pipe(callback(done))
.pipe(send());
});
`

Joining streams

Streams can also be joined for more complex scenarios. Here are a few examples:

- Emit 2 different requests with a total concurrency of 50

`js
join(emit(r1), emit(r2))
.pipe(concurrent(50))
.pipe(summary())
.pipe(send());
`

- Emit 2 different requests with a concurrency of 50 each

`js
var s1 = emit(r1).pipe(concurrent(50));
var s2 = emit(r2).pipe(concurrent(50));
join(s1, s2)
.pipe(summary())
.pipe(send());
``

It's up to each reporter to either give global stats, or group the report by request URL.