Adblock Plus core

This repository contains the generic Adblock Plus code that's shared between platforms. This repository is not designed to be used directly, but instead to serve as a dependency for adblockpluschrome and libadblockplus.

Resources

One of the feature of Adblock Plus is to allow redirecting requests to inactive versions of a resource (script, image, or media).

To that effect we have some resources generated as data built into Adblock Plus.

As there is no "build" for adblockplsucore, if you want to modify these resources, you'll need to regenerate the file data/resources.json.

Adding the new resource for $redirect:

• Edit build/assets/index.json. The fields are defined as follow:
  • name: The name of the resource as used for the $rewrite filter option.
  • type: The MIME type of the content.
  • text: If the resource is pure text, you can use this for the text content. If the resource is binary data, use file instead.
  • file: The name of the file in build/assets/ that will be included in the output as base64. If there is a text value, don't include this.
  • comment: an optional comment. This won't be part of the output.
• Add the binary files referenced in the file entry for the new resource in build/assets/. They should be checked into the repository.
• Run the resources package script using npm with the command npm run uppdate-resources. This will generate the file data/resources.json. This file is also managed by the version control system and should be part of the checkin.

Running the unit tests

Requirements

In order to run the unit test suite you need Node.js 12.17.0 or higher. Once Node.js is installed please run npm install in the repository directory in order to install the required dependencies.

Running all tests

npm test will run all tests in the test directory of the repository.

Running specific tests

You can specify specific test files or directories on the command line, e.g.: npm test test/synchronizer.js test/browser/elemHideEmulation.js.

Running the browser tests in a real browser

The tests under test/browser require a browser environment. npm test will run these in a headless browser, with each module being loaded in a new frame.

The default is to run in both Chromium (using the remote interface) and Firefox. You can select which runners to use by setting the BROWSER_TEST_RUNNERS environment, the default is "chromium_remote,firefox". Possible values (separated by a ',') are:

• "chromium_remote": Chromium 60 (using the remote interface)
• "chromium": Chrome 63 (using WebDriver)
• "firefox": Firefox 57 (using WebDriver)

You can not set a specific version of the browser at runtime.

Browser tests run headless by default (except on Windows). If you want to disable headless mode on the WebDriver controlled tests, set the BROWSER_TEST_HEADLESS environment to 0.

Linting

You can lint the code using ESLint by running npm run lint.

Benchmarking

We do care about performance, and we want to keep an eye on changes that might degrade the previous state.

Our package has a few helpers, npm run ... commands, to do so, based on most popular filters lists used out there, focused on both bootstrap and heap consumption.

Bootstrapping benchmarks

Each machine is different, so we decided to not pollute the repository with files that could be meaningless across different hardware.

This means that the very first time benchmarking is needed, we should save the current results, so that we can incrementally monitor changes in the branch.

To store, at any time, benchmarks references, we need to run the following:

npm run benchmark:save

This snapshot will contain the latest performance improvements we'd like to match against, while changing code in our own branch.

Benchmark cleanup

If benchmark results are polluted with too many data, you can run

npm run benchmark:cleanup

This command performs benchmark (without saving it) and cleans benchmark results file - saving only efficient runs (for each filters set and for each parameter).

Benchmark reset

If the best results are not satisfying, or impossible to reach, due new requirements - remove benchmarkresults.json manually. Next run with ":save" flag will create new files.

Benchmark - filter lists

Both Matching & Filtering measurements requires filters to measure against. You can manipulate which set of filter lists to use by setting proper flags: --filter-list=All for filter lists supported flags:

• All for all filter lists (Easylist, Easylist+AA, Testpages, Easyprivacy)
• EasyList+AA for Easylist +AA
• EasyList for Easylist only

--match-list=slowlist for matching filter lists supported flags:

• slowlist (for list of slow filters)
• unitlist (for list used in unit tests)
• all (for combination of slowfilters & unittests)

Benchmark cache

By default, if filters files are not found, these are downloaded in the ./benchmark folder to avoid downloading different files to compare per each consecutive run.

However, from time to time, or after a cleanup, it is recommended to remove these files manually, and download latest.

Please note: downloading doesn't work for Matching filter lists.

Benchmarking

The npm run benchmark command will visually show, in console, what is the current heap memory state, and bootstrap time for both filter engine & matching.

This operations does not store results in the benchmark history, so it can be executed incrementally, while we code.

Benchmark - matching

Part of benchmark measurement is Matching against various filters. When benchmark is run with flag: --match then by default it will run 3 rounds of same matching per filters. Number of rounds can be adjusted by changing --rounds argument in benchmark run: node --expose-gc benchmark.js --matchList=slowlist --match --rounds=23 --dt

Benchmark results

If we'd like to compare current changes with heap and bootstrap we had before, npm run benchmark:compare would take care of that, producing a table with differences between the previous, stored, state, and the current one.

Please note that the comparison is always against most efficient results generated via all previous saved benchmarks.

Please note, as benchmarks results might be compromised by various factors, such as your computer dedicating CPU for other tasks while running, there is a threshold margin to consider, where only multiple, repeated, better scores can be considered an effective improvement, as running the same benchmark twice, might produce diversions between scores itself, without changing code at all.

Documentation

The module documentation is generated with jsdoc. To generate the documentation use:

npm run docs

CI will generate the documentation for master and next branches. It is available at:

• For next (the development branch): [https://eyeo.gitlab.io/adblockplus/abc/adblockpluscore/next/docs/]
• For master (the release branch): [https://eyeo.gitlab.io/adblockplus/abc/adblockpluscore/master/docs/]

Node.js module

adblockpluscore is available as an npm module for Node.js. See: https://www.npmjs.com/package/adblockpluscore

You can install it with:

npm install adblockpluscore

Or you can simply add it to your package.json.

let {contentTypes, filterEngine} = require("adblockpluscore");

async function main()
{
  await filterEngine.initialize(
    [
      "/annoying-ad.$image",
      "||example.com/social-widget.html^"
    ]
  );

  let resource = {
    url: "https://ad-server.example.net/annoying-ad.png",
    documentURL: "https://news.example.com/world.html"
  };

  let filter = filterEngine.match(resource.url, contentTypes.IMAGE,
                                  new URL(resource.documentURL).hostname);
  console.log(filter); // prints "/annoying-ad.$image"
}

if (require.main == module)
  main();