README
workload
Sends HTTP requests to a server to mimic a natual load.
The requests are randomized using weights, so certain requests appear more often than others.
It's also possible to mimic regular working hours so that the average number of requests are lower at night and in the weekends.
This module is not intended to benchmark an HTTP server. If that's your use-case I suggest you take a look at autocannon instead. This module is meant to help you simulate a real-world workload over a longer period of time.
Installation
For use from the command line, install globally:
npm install workload --global
For use programmatically:
npm install workload --save
CLI Usage
Example making max 60 requests per minute to 5 different URL's with different weights:
workload --max 60 \
POST,http://example.com/signup,"Hello World" \
10,http://example.com/ \
2,http://example.com/foo \
4,http://example.com/bar \
8,http://example.com/baz
Run workload --help
for all options.
Programmatic Usage
var Workload = require('workload')
var workload = new Workload({
max: 30, // make a request once every 2 seconds maximum
filter: Workload.stdFilters.workingHours,
requests: [
{weight: 1, url: 'http://example.com/signup', method: 'POST', body: '...'},
{weight: 10, url: 'http://example.com/'},
{weight: 2, url: 'http://example.com/foo'},
{weight: 4, url: 'http://example.com/bar'},
{weight: 8, url: 'http://example.com/baz'}
]
})
// stop after 1 minute
setTimeout(function () {
workload.stop()
}, 60000)
API
var workload = new Workload(options)
Create a new workloader. The workload
object is an EventEmitter.
The constructor takes the following options:
requests
- An array ofrequest
objects (see below)max
- The maximum number of requests to make per minute (defaults to12
)headers
- An object containing the default HTTP headers to use for each requestfilter
- An optional filter single function (shorthand forfilters: [filter]
) - see Filters for detailsfilters
- An optional array of filter functions which will be called sequentially - see Filters for details
Each request
object can contain the following properties:
url
- The URL to requestmethod
- The HTTP method to use (defaults toGET
)weight
- The chance that this request will be performed compared to the other requests (defaults to1
)headers
- A object containing HTTP headers to use for the request (overrulesoptions.headers
)body
- Entity body forPATCH
,POST
andPUT
requests. Must be aBuffer
,String
orReadStream
. Ifjson
is true, then body must be a JSON-serializable objectjson
- Sets body to JSON representation of value and addsContent-type: application/json
header. Additionally, parses the response body as JSON- For additional options, see the options accepted by the request module.
error
Event: Emitted if an error occurs during one of the requests.
visit
Event: Emitted every time a request have been successfully performed. An object with the following properties is emitted:
request
- The request options used when making the requestresponse
- The response object (anhttp.IncomingMessage
instance)body
- The body of the response
workload.stop()
Stop making requests.
Workload.stdFilters.workdays
This filter lowers the chances of a request being made during weekends.
Workload.stdFilters.workingHours
This filter lowers the chances of a request being made during weekends and at night.
Workload.stdFilters.expand
This filter expands braces in URL's and picks a random matching URL.
For instance, given a request with a URL of
http://example.com/foo/{1..10}
this filter will replace the {1..10}
part of the URL with a random number between 1 and 10. So the actual
requested URL might be /foo/4
.
Filters
A filter is a function that will either lower the chance of a request being made or modify the request in some way.
The function is called every time a request is ready to be made. It's passed the request object and a callback. Whether or not it calls the callback determins if the request is performed or not.
It's also possible to modify the request inside a filter function by manipulating the request object and passing it as an argument to the callback.
Example filter function that only makes requests between 6am and 7am:
function (request, next) {
var hour = (new Date()).getHours()
if (hour === 6) next()
}
Example filter function that modifies the request URL:
function (request, next) {
request.url += '/' + Math.random()
next(request)
}
Acknowledgements
This project was kindly sponsored by Opbeat.
License
MIT