Create a filter list
Creating a filter list
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Creating a filter list
Last updated
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A filter list is a text file that contains, in this order:
An [Adblock Plus] header line, to identify itself as following the
A collection of optional special comments, one per line
A collection of filters or normal comments, one per line
The header line must be the first line of the file.
It should say [Adblock Plus]. It might also contain a version number, for example [Adblock Plus 2.0], but the version is ignored by the eyeo Browser Ad-Filtering Solution.
Special comments are a single block of consecutive comments that start from an exclamation mark (!) and follow a key:value semantic.
The Browser Ad-Filtering Solution interprets the following special comments:
Redirect
URL
Instead of parsing this filter list, download a filter list from the provided URL. Useful when the list location has changed and an http redirect cannot be implemented.
! Redirect: https://new-location.com/list.txt
Title
String
Human-readable title of the filter list. Returned by:
C++: Subscription::GetTitle()
Java: Subscription::title()
JavaScript: Subscription.title
! Title: My filters
Version
String
An arbitrary string that describes the current version of the list. Returned by:
C++: Subscription::GetCurrentVersion()
Java: Subscription::version()
JavaScript: Subscription.current_version
! Version: 202305310750
! Version: 5.0.4
Expires
Number, optionally followed by text
How frequently should the Solution download updates. In number of days, unless followed by a text starting from h, then in number of hours. Following text is ignored.
! Expires: 1 days (update frequency)
! Expires: 1 hours
! Expires: 7 (weekly)
There are other special comments that may be interpreted by other eyeo Ad-Filtering Solution, for example:
Homepage
License
Checksum
Parsing of the special comments block stops after encountering a line that isn't a ! key : value. All further comments are treated as not special and ignored.
This is probably the most important block of a filter list - the actual filters.
Comment lines start from an exclamation mark (!) and are skipped during parsing.
The filters are parsed until the end of file.
For a big working example, consider https://easylist-downloads.adblockplus.org/easylist.txt
For a more minimal example, compare the filter list used for test pages: https://abptestpages.org/en/abp-testcase-subscription.txt
For safety, the Browser Ad-Filtering Solution will only download filter lists from HTTPS servers, HTTP is not allowed.
An exception is localhost - the Solution will download a filter list from http://localhost/any/path.txt to facilitate local development and testing.
The eyeo Browser Ad-Filtering Solution will periodically download filter list updates. It will respect the interval specified in ! Expires or revert to the default period of 5 days.
The update check interval is clamped between 1 hour and 14 days.
If a new version of the filter list fails to download or parse correctly, the SDK will retain the old version and retry the update in an hour.
You can write one filter rule per line, as described in .
and header filters will be ignored. They are only allowed on .
You can still add snippet and header filters as individual custom filters, as explained .