README.md

fuzzer

A fuzzer for testing. This implements mutation fuzzing, in which an expect input is mutated (changed) many times in order to trigger unexpected behavior or crashes.

install

npm install fuzzer

api

fuzzer.mutate.object(obj)

Generate a mutated version of an object. This does not modify the object directly, but returns a modified copy. This mutation will increment and decrement numbers, randomize arrays, remove properties, and more.

fuzzer.mutate.string(str)

Generate a mutated version of a string, with reversed, removed, and added characters.

fuzzer.seed(number)

Seed the random number generator random-js that determines mutations. By calling this function with the same number, you can generate the same mutations consistently.

fuzz-get

If you install this globally it provides a single cli utility called fuzz-get.

npm install -g fuzzer
fuzz-get "./bin/fuzz-get "http://localhost:8889/foo/bar/your/rest/api"

This will run mutated requests against your server continously - it will mutate the path requested into other incorrect requests, and log in the form:

HTTP200:/foo/bar/your/rest/api
HTTP404:/foo/baryour/rest/api

So you can pipe into | grep "HTTP500" if you wish.

example

var test = require('tap').test,
    fuzzer = require('fuzzer');

fuzzer.seed(0);

test('something', function(t) {
    var generator = fuzzer.mutate.object(yourTestingInput);
    for (var i = 0; i < 1000; i++) {
        t.doesNotThrow(function() {
            yourLibrary(generator());
        });
    }
});