This repository contains a library for working with Adblock Plus filter lists, a script for rendering diffs between filter lists, and the script that is used for building Adblock Plus filter lists from the form in which they are authored into the format suitable for consumption by the adblocking software (aka rendering).
Contents
Prerequisites:
- Linux, Mac OS X or Windows (any modern Unix should work too),
- Python (2.7 or 3.5+),
- pip.
To install:
$ pip install --upgrade python-abp
The filter lists are originally authored in relatively smaller parts focused on particular types of filters, related to a specific topic or relevant for a particular geographical area. We call these parts filter list fragments (or just fragments) to distinguish them from full filter lists that are consumed by the adblocking software such as Adblock Plus.
Rendering is a process that combines filter list fragments into a filter list. It starts with one fragment that can include other ones and so forth. The produced filter list is marked with a version and a timestamp.
Python-abp contains a script that can do this called flrender:
$ flrender fragment.txt filterlist.txt
This will take the top level fragment in fragment.txt, render it and save it
into filterlist.txt.
The flrender script can also be used by only specifying fragment.txt:
$ flrender fragment.txt
in which case the rendering result will be sent to stdout. Moreover, when
it's run with no positional arguments:
$ flrender
it will read from stdin and send the results to stdout.
Fragments might reference other fragments that should be included into them. The references come in two forms: http(s) includes and local includes:
%include http://www.server.org/dir/list.txt% %include easylist:easylist/easylist_general_block.txt%
The http include contains a URL that will be fetched and inserted at the point
of reference.
The local include contains a path inside the easylist repository.
flrender needs to be able to find a copy of the repository on the local
filesystem. We use -i option to point it to to the right directory:
$ flrender -i easylist=/home/abc/easylist input.txt output.txt
Now the local include referenced above will be resolved to:
/home/abc/easylist/easylist/easylist_general_block.txt
and the fragment will be loaded from this file.
Directories that contain filter list fragments that are used during rendering
are called sources.
They are normally working copies of the repositories that contain filter list
fragments.
Each source is identified by a name: that's the part that comes before ":" in
the include instruction and it should be the same as what comes before "=" in
the -i option.
Commonly used sources have generally accepted names. For example the main
EasyList repository is referred to as easylist.
If you don't know all the source names that are needed to render some list,
just run flrender and it will report what it's missing:
$ flrender easylist.txt output/easylist.txt Unknown source: 'easylist' when including 'easylist:easylist/easylist_gener al_block.txt' from 'easylist.txt'
You can clone the necessary repositories to a local directory and add -i
options accordingly.
A diff allows a client running ad blocking software such as Adblock Plus to update the filter lists incrementally, instead of downloading a new copy of a full list during each update. This is meant to lessen the amount of resources used when updating filter lists (e.g. network data, memory usage, battery consumption, etc.), allowing clients to update their lists more frequently using less resources.
python-abp contains a script called fldiff that will find the diff between
the latest filter list, and any number of previous filter lists:
$ fldiff -o diffs/easylist/ easylist.txt archive/*
where -o diffs/easylist/ is the (optional) output directory where the diffs
should be written, easylist.txt is the most recent version of the filter
list, and archive/* is the directory where all the archived filter lists are.
When called like this, the shell should automatically expand the archive/*
directory, giving the script each of the filenames separately.
In the above example, the output of each archived list[version].txt will be
written to diffs/diff[version].txt. If the output argument is omitted, the
diffs will be written to the current directory.
The script produces three types of lines, as specified in the technical specification:
- Special comments of the form
! <name>:[ <value>] - Added filters of the form
+ <filter-text> - Removed filters of the form
- <filter-text>
python-abp can also be used as a library for parsing filter lists. For example to read a filter list (we use Python 3 syntax here but the API is the same):
from abp.filters import parse_filterlist
with open('filterlist.txt') as filterlist:
for line in parse_filterlist(filterlist):
print(line)If filterlist.txt contains this filter list:
[Adblock Plus 2.0] ! Title: Example list abc.com,cdf.com##div#ad1 abc.com/ad$image @@/abc\.com/
the output will look something like:
Header(version='Adblock Plus 2.0')
Metadata(key='Title', value='Example list')
EmptyLine()
Filter(text='abc.com,cdf.com##div#ad1', selector={'type': 'css', 'value': 'div#ad1'}, action='hide', options=[('domain', [('abc .com', True), ('cdf.com', True)])])
Filter(text='abc.com/ad$image', selector={'type': 'url-pattern', 'value': 'abc.com/ad'}, action='block', options=[('image', True)])
Filter(text='@@/abc\\.com/', selector={'type': 'url-regexp', 'value': 'abc\\.com'}, action='allow', options=[])The abp.filters module also exports a lower-level function for parsing
individual lines of a filter list: parse_line. It returns a parsed line
object just like the items in the iterator returned by parse_filterlist.
For further information on the library API use help() on abp.filters and
its contents in an interactive Python session, read the docstrings, or look at
the tests for some usage examples.
Further processing of blocks of filters separated by comments can be performed
using to_blocks function from abp.filters.blocks:
from abp.filters import parse_filterlist
from abp.filters.blocks import to_blocks
with open(fl_path) as f:
for block in to_blocks(parse_filterlist(f)):
print(json.dumps(block.to_dict(), indent=2))Use help() on abp.filters.blocks for more information.
Unit tests for python-abp are located in the /tests directory. Pytest
is used for quickly running the tests during development. Tox is used for
testing in different environments (Python 2.7, Python 3.5+ and PyPy) and code
quality reporting.
Use tox for a comprehensive report of unit tests and test coverage:
$ tox
When adding new functionality, add tests for it (preferably first). If some
code will never be reached on a certain version of Python, it may be exempted
from coverage tests by adding a comment, e.g. # pragma: no py2 cover.
All public functions, classes and methods should have docstrings compliant with NumPy/SciPy documentation guide. One exception is the constructors of classes that the user is not expected to instantiate (such as exceptions).
python-abp can be installed from PyPI or from the source code, either
directly onto a system or in a virtual environment.
To install from PyPI:
$ pip install -U python-abp
To install from a local source, clone the repo and then:
$ pip install -U /path/to/python-abp
To use the virtual environment, it must first be created. Python 2 and 3 use different scripts to create a virtualenv.
In Python 2:
$ virtualenv env
In Python 3:
$ python3 -m venv env
Then, use the virtualenv's version of pip to install python-abp, either from PyPI or from source (as shown above):
$ env/bin/pip install -U python-abp
For more information about virtualenv, please see the User Guide and the docs.
In R, python-abp can be imported with reticulate:
> library(reticulate)
> use_virtualenv("~/path/to/env", required=TRUE) # If using virtualenv
> abp <- import("abp.filters.rpy")Now you can use the functions with abp$functionname, e.g.
abp$line2dict("@@||g.doubleclick.net/pagead/$subdocument,domain=hon30.org")
For more information about the reticulate package, see their guide.