Dependency cruiser

Validate and visualize dependencies. With your rules. JavaScript. TypeScript. CoffeeScript. ES6, CommonJS, AMD.

What's this do?

This runs through the dependencies in any JavaScript, TypeScript, LiveScript or CoffeeScript project and ...

... validates them against (your own) rules
... reports violated rules
- in text (for your builds)
- in graphics (for your eyeballs)

As a side effect it can generate cool dependency graphs you can stick on the wall to impress your grandma.

How do I use it?

Install it

npm install --save-dev dependency-cruiser to use it as a validator in your project or...
npm install --global dependency-cruiser if you just want to to inspect multiple projects.

Show stuff to your grandma

To create a graph of the dependencies in your src folder, you'd run dependency cruiser with output type dot and run GraphViz dot on the result. In a one liner:

depcruise --exclude "^node_modules" --output-type dot src | dot -T svg > dependencygraph.svg

You can read more about what you can do with --exclude and other command line options in the command line interface documentation.
Real world samples contains dependency cruises of some of the most used projects on npm.

Validate things

Declare some rules

The easy way to get you started:

depcruise --init

This will create a .dependency-cruiser.json with some rules that make sense in most projects (detecting circular dependencies, dependencies missing in package.json, production code relying on dev- or optionalDependencies, ...).

Start adding your rules by tweaking that file.

Sample rule:

{
    "forbidden": [{
        "name": "not-to-test",
        "comment": "don't allow dependencies from outside the test folder to test",
        "severity": "error",
        "from": { "pathNot": "^test" },
        "to": { "path": "^test" }
    }]
}

To read more about writing rules check the writing rules tutorial or the rules reference
You can find the --init-rules set here

Report them

depcruise --validate .dependency-cruiser.json src

This will validate against your rules and shows any violations in an eslint-like format:

There's more ways to report validations; in a graph (like the one on top of this readme) or in a table.

Read more about the err, dot, csv and html reporters in the command line interface documentation.
dependency-cruiser uses itself to check on itself in its own build process; see the dependency-cruise target in the Makefile