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0.7.1 • Public • Published


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NPM install

UMDLib is a template for writing micro UMD Javascript libraries that run both on Node.js and inside the browser.

UMDLib relies on Mocha and Chai for unitary testing. It relies on Istanbul for code coverage.

UMDLib uses Travis CI for continuous integration and Coveralls.io to display test coverage.

Quick Startup

You can easily get your first UMD library running in a couple of minutes by just typing a few command lines. But first, you need to create an empty folder. It will contain your library.

Then, you have to install the umdlib package globally. Open a terminal session and type the command line:

npm install umdlib -g

Or, if you don't have the rights to install umdlib globally, you can install it locally in your project. Open a terminal session, move to your working directory - the empty folder you created - and type the following command line:

npm install umdlib

Now populate your empty folder and create your first UMD library:

// populate
umdlib populate -n myapp
// Or, if you installed the package locally:
./node_modules/umdlib/bin/umdlib.js populate -n myapp
// Install Node.js packages
npm install

Now your folder contains the following files:

Your project Folder
      |_ docs                 // The Gitbook documentation of your project,
      |_ lib
      |   |_ lib.js           // Your built ES5 module,
      |_ src
      |   |_ _footer           // The UMD footer,
      |   |_ _header           // The UMD header,
      |   |_ ...               // The UMD Module core,
      |_ tasks
      |   |_ ...              // The Gulp tasks to build your project,
      |_  test
      |     |_ main.js        // Your Mocha, Chai test file,
      |_ .eslintrc            // A Configuration file for the ESLint linter tool (if you use it),
      |_ .gitignore           // Files that Git must ignore (if you use git),
      |_ .travis.yml          // A configuration file for Travis CI (if you use it),
      |_ .CHANGELOG.md        // The changes between your different versions,
      |_ .gulpfile.js         // The main Gulp task,
      |_ index.js             // The link to your ES5 library,
      |_ LICENSE.md           // The license that applies to your library (here MIT),
      |_ package-lock.json    // The NPM dependency tree,
      |_ package.json         // The NPM package file,
      |_ README.md            // Your README file,

This folder is now a NPM package.

How to build it

The file gulpfile.js contains the build instructions. These instructions populate the folder lib from the sources files included in the folder src.

gulpfile.js implements two operations for the build:

  • the command npm run build creates the library at the execution,
  • and the command npm run watch updates the library when one of the source files is modified.

How to test it

Your package.json file contains three scripts to test your UMD library:

  • npm run test,
  • npm run check-coverage,
  • npm run display-coverage.

npm run test executes the tests and computes the test coverage.

npm run check-coverage checks if the test coverage matches the requirements. Here 100%.

npm run display-coverage opens your browser and reports the test coverage.

How to create a distribution version

Your package.json file contains a script to build a distribution library:

  • npm run makedist

The script makedist adds a license header to the library and creates a minified version.

How to use it

On Node.js, your project folder is viewed as a NPM package. Choose a working directory outside your project folder, create a folder node_modules and copy your project folder into node_modules. Then, on your terminal, type (at your working directory level):

> var mylib = require('toto');
> mylib.getString();
'I am a string!'
> mylib.getArray();
[ '1', '2', '3' ]

On the browser, pick-up the JS file lib/umdlib.js and add it as a script in your HTML file. umdlib is an immediately-invoked function expression. It attaches the UMDLib variable to the current context.

<!DOCTYPE html>
    <script src="umdlib.js"></script>





npm i umdlib

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