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0.2.3 • Public • Published

KATT player Build Status

KATT player is a mock HTTP server that replies with HTTP responses based on KATT blueprints.

KATT blueprints describe a scenario as a sequence of HTTP requests and responses (the pair is called an HTTP transaction).

KATT player instantiates an HTTP server that loads these scenarios and, given a reference to one of them, it can respond to a HTTP request with the HTTP response prescribed by the referenced scenario.

The HTTP response is decided by a KATT player engine. Two engines are built-in: one that validates the incoming requests against the blueprint (linear-check), and one that doesn't and just blindly replies with the consecutive response (linear). The former is the default.

Built-in engines

These two engines will look at

  • the request's cookie katt_scenario to decide which scenario to focus on (e.g. basename of the scenario)
  • the request's cookie katt_transaction to decide the request to match against and which response is suitable (defaults to 0)

Both engines will automatically set a response header Set-Cookie in order to advance the transaction count.

The linear-check engine can have the validation turned off temporarily via a request header X-KATT-Dont-Validate.

You can see an example here.

Custom engines

Custom engines may be implemented in order to add support for dealing with KATT recall structures, for example.

There are no restrictions or requirements at all.


# NPM distribution 
npm install katt-player
# GIT source 
git clone --recurse-submodules [THIS_REPO_URL]
npm install


katt-player [--engine=linear] [--port=1337] FOLDER      # default engine is linear, port is 1337 
katt-player [--engine=linear] [--port=1337] FILE1 FILE2 # accepts blueprints as well 
katt-player --engine=path/to/engine.js FOLDER           # use a custom engine 
NODE_ENV=development katt-player FOLDER                 # enable logging to console, instead of console.log 
kattPlayer = require 'katt-player'
app = kattPlayer kattPlayer.engines.linear
app.load 'FOLDER''FILE1''FILE2'
app.listen 1337


Apache 2.0




npm i katt-player

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