A free and open source library for publishers to quickly implement header bidding.

This README is for developers who want to contribute to Prebid.js. Additional documentation can be found at the Prebid homepage. Working examples can be found in the developer docs.

Table of Contents

• Install
• Build
• Run
• Contribute

$ git clone https://github.com/prebid/Prebid.js.git
$ cd Prebid.js
$ yarn install

Prebid supports the yarn npm client. This is an alternative to using npm for package management, though npm install will continue to work as before.

For more info, see the Yarn documentation.

Note: You need to have NodeJS 4.x or greater installed.

To build the project on your local machine, run:

$ gulp serve

This runs some code quality checks, starts a web server at http://localhost:9999 serving from the project root and generates the following files:

• ./build/dev/prebid.js - Full source code for dev and debug
• ./build/dev/prebid.js.map - Source map for dev and debug
• ./build/dist/prebid.js - Minified production code
• ./prebid.js_<version>.zip - Distributable zip archive

The standard build output contains all the available modules from within the modules folder.

You might want to exclude some/most of them from the final bundle. To make sure the build only includes the modules you want, you can specify the modules to be included with the --modules CLI argument.

For example, when running the serve command: gulp serve --modules=openxBidAdapter,rubiconBidAdapter,sovrnBidAdapter

Building with just these adapters will result in a smaller bundle which should allow your pages to load faster.

Build standalone prebid.js Prebid now supports the yarn npm client. This is an alternative to using npm for package management, though npm will continue to work as before.

For more info about yarn see https://yarnpkg.com

• Clone the repo, run yarn install

• Then run the build:

    $ gulp build --modules=openxBidAdapter,rubiconBidAdapter,sovrnBidAdapter
  

Alternatively, a .json file can be specified that contains a list of modules you would like to include.

$ gulp build --modules=modules.json

With modules.json containing the following

[
  "openxBidAdapter",
  "rubiconBidAdapter",
  "sovrnBidAdapter"
]

Build prebid.js using Yarn for bundling

In case you'd like to explicitly show that your project uses prebid.js and want a reproducible build, consider adding it as an yarn dependency.

• Add prebid.js as a yarn dependency of your project: yarn add prebid.js

• Run the prebid.js build under the node_modules/prebid.js/ folder

    $ gulp build --modules=path/to/your/list-of-modules.json
  

Most likely your custom prebid.js will only change when there's:

• A change in your list of modules
• A new release of prebid.js

Having said that, you are probably safe to check your custom bundle into your project. You can also generate it in your build process.

To lint the code:

gulp lint

To run the unit tests:

gulp test

To run tests for a single file:

gulp test --file "path/to/spec/file.js"

To generate and view the code coverage reports:

gulp test-coverage
gulp view-coverage

For end-to-end testing, edit the example file ./integrationExamples/gpt/pbjs_example_gpt.html:

1. Change {id} values appropriately to set up ad units and bidders
2. Set the path to Prebid.js in your example file as shown below (see pbs.src).

For development:

(function() {
    var d = document, pbs = d.createElement('script'), pro = d.location.protocol;
    pbs.type = 'text/javascript';
    pbs.src = ((pro === 'https:') ? 'https' : 'http') + './build/dev/prebid.js';
    var target = document.getElementsByTagName('head')[0];
    target.insertBefore(pbs, target.firstChild);
})();

For deployment:

(function() {
    var d = document, pbs = d.createElement('script'), pro = d.location.protocol;
    pbs.type = 'text/javascript';
    pbs.src = ((pro === 'https:') ? 'https' : 'http') + './build/dist/prebid.js';
    var target = document.getElementsByTagName('head')[0];
    target.insertBefore(pbs, target.firstChild);
})();

Build and run the project locally with:

gulp serve

This runs lint and test, then starts a web server at http://localhost:9999 serving from the project root. Navigate to your example implementation to test, and if your prebid.js file is sourced from the ./build/dev directory you will have sourcemaps available in your browser's developer tools.

To run the example file, go to:

• http://localhost:9999/integrationExamples/gpt/pbjs_example_gpt.html

As you make code changes, the bundles will be rebuilt and the page reloaded automatically.

Many SSPs, bidders, and publishers have contributed to this project. 60+ Bidders are supported by Prebid.js.

For guidelines, see Contributing.

Our PR review process can be found here.

To add a bidder adapter module, see the instructions in How to add a bidder adaptor.

Please do NOT load Prebid.js inside your adapter. If you do this, we will reject or remove your adapter as appropriate.

Code quality is defined by .eslintrc and errors are reported in the terminal.

If you are contributing code, you should configure your editor with the provided .eslintrc settings.

    $ gulp test --watch --browsers=chrome

This will run tests and keep the Karma test browser open. If your prebid.js file is sourced from the ./build/dev directory you will also have sourcemaps available when using your browser's developer tools.

• To access the Karma debug page, go to http://localhost:9876/debug.html

• For test results, see the console

• To set breakpoints in source code, see the developer tools

Detailed code coverage reporting can be generated explicitly with

    $ gulp test --coverage

The results will be in

    ./build/coverage

Note: Starting in June 2016, all pull requests to Prebid.js need to include tests with greater than 80% code coverage before they can be merged. For more information, see #421.

For instructions on writing tests for Prebid.js, see Testing Prebid.js.

Prebid.js is supported on IE10+ and modern browsers.

Review our governance model here.