lein-npm

Leiningen plugin for enabling Node based ClojureScript projects.

Installation

To enable lein-npm for your project, put the following in the :plugins vector of your project.clj file:

Managing npm dependencies

You can specify a project's npm dependencies by adding an :npm map to your project.clj with a :dependencies or :devDependencies key. These correspond to the "dependencies" and "devDependencies" keys in a package.json file.

:npm {:dependencies [[underscore "1.4.3"]
                     [nyancat "0.0.3"]
                     [mongodb "1.2.7"]
                     ;; Other types of dependencies (github, private npm, etc.) can be passed as a string
                     ;; See npm docs though as this may change between versions.
                     ;; https://docs.npmjs.com/files/package.json#dependencies
                     [your-module "github-username/repo-name#commitish"]]}

These dependencies, and any npm dependencies of packages pulled in through the regular :dependencies, will be installed through npm when you run either lein npm install or lein deps.

Transitive dependencies

lein-npm looks at your project's dependencies (and their dependencies, e.t.c.) to check if there are any NPM libraries in :dependencies in the project.clj to install. Your testing and development libraries should go into :devDependencies. The only things that should go into :dependencies are NPM dependencies that are required for people to use your library.

Presisting package.json

The generated package.json file will not be persisted by default. In cases where you wish to persist it, set the :write-package-json to true:

:npm {:dependencies [[source-map-support "0.4.6"]]
      :write-package-json true}

Invoking npm

You can execute npm commands that require the presence of a package.json file using the lein npm command. This command creates a temporary package.json based on your project.clj before invoking the npm command you specify. The keys name, description, version and dependencies are automatically added to package.json. Other keys can be specified in your project.clj at :package under :npm.:

  :npm {:package {:scripts {:test "testem"}}}

$ lein npm install        # installs project dependencies
$ lein npm ls             # lists installed dependencies
$ lein npm search nyancat # searches for packages containing "nyancat"

Bower dependencies

lein-bower is a related Leiningen plugin that performs the same service for Bower dependencies. lein-bower itself depends on lein-npm.

Running ClojureScript apps

The plugin installs a lein run hook which enables you to specify a JavaScript file instead of a Clojure namespace for the :main key in your project.clj, like this:

:main "js/main.js"

If :main is a string that refers to a file that exists and ends with .js, it will launch this file using npm start, after first running npm install if necessary. Any command line arguments following lein run will be passed through to the Node process. Note that a scripts.start record will be automatically added to the generated package.json file, simply containing node <value of :main>, but you can override this using the :package key under :npm as described above. The :main key will still have to exist and point to a file ending in .js, though, or lein run will stay with its default behaviour.

Changing the directory used

npm does not allow you to put stuff anywhere besides node_modules, even if that name is against your religion, however, you can change the root used by lein-npm to be something other than your project root like this:

:npm {:root "resources/public/js"}

Or you can use a keyword to look the path up in your project map:

:npm {:root :target-path}

License

Copyright 2012 Bodil Stokke

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0.

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.