krabbel

Krabbel

• Krabbel
  • Purpose
  • Installation
  • Usage
  • Licence

Purpose

When writing web applications (server and/or client) debugging, refactoring and testing brings you only so far. One of the things that are not easy to mock or fake is a certain workload that shows you how your application is behaving under load. This is were krabbel comes in: it's basically just a web-crawler that tries to get all local links within an URL as soon as possible. Its sole purpose is to produce some kind of stress test that shows how well your web-server reacts under load.

Installation

You can use Go to install this package for you:

go get -u github.com/mwat56/krabbel

Usage

First you've to compile the main file

go build app/krabbel.go

When running krabbel without commandline argments you'll get a short help-text:

$ ./krabbel

Usage: ./krabbel [OPTIONS]

-cgi
	<bool> use CGI arguments (default true)
-quiet
	<bool> suppress 'Reading…' output
-url string
	<string> the URL to start crawling

$_

So you run it by calling it with the start URL to use, e.g.

./krabbel -url http://127.0.0.1:8080/

Depending on the number of linked pages it might run a few seconds while printing out the respective page processed and finally showing a line like

2019/12/18 23:37:41 checked 3422 pages in 5.9901556s

The actual number of pages shown and the time used will, of course, change depending on the load of the computer you use to run the tool and the load of the server tested. Things like routing details and network latency will take their time as well. In other words: This is not a benchmarking tool.

Sometimes the URLs in page links contain socalled CGI arguments carrying session and/or page specific data. In this cases the respective server's execution path may (or may not) depend on the value of that CGI argument(s). krabbel offers a second commandline option -cgi; this is a boolean value (default value is true) determining whether to use CGI argument(s) when crawling through the web pages or not:

./krabbel -url=http://127.0.0.1:8080/ -cgi=false

Here all possible CGI argument(s) of linked URLs will be ignored while crawling through the given URL's links.

By default krabbel prints out every URL it processes. If you don't want/need that you can use the -quiet option to suppress those messages:

./krabbel -url=http://127.0.0.1:8080/ -cgi=false -quiet=true

Here only the final statistics line will be printed to screen.

Please note that you should use this tool only with web-servers/-pages that you're personally responsible for. Do not use this tool with servers you don't own – that's not only impolite but also illegal in certain countries.

Licence

    Copyright © 2019, 2020 M.Watermann, 10247 Berlin, Germany
                    All rights reserved
                EMail : <support@mwat.de>

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version.

This software is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

You should have received a copy of the GNU General Public License along with this program. If not, see the GNU General Public License for details.