Plugins
Built-in plugins
This is a list of built-in plugins that are considered stable.
See the Plugins section of the user guide for details on how built-in plugins are loaded.
reader.enclosure_dedupe
Deduplicate the enclosures of an entry by enclosure URL.
reader.entry_dedupe
Deduplicate the entries of a feed.
Sometimes, the format of the entry id changes for all the entries in a feed,
for example from example.com/123 to example.com/entry-title.
Because id uniquely identifies the entries of a feed,
this results in them being added again with the new ids.
entry_dedupe addresses this
by copying entry user attributes
like read or important from the old entries to the new one,
and deleting the old entries.
Duplicates are entries with the same title and the same summary/content.
By default, this plugin runs only for newly-added entries.
To run it for the existing entries of a feed,
add the .reader.dedupe.once tag to the feed;
the plugin will run on the next feed update, and remove the tag afterwards.
To run it for the existing entries in a feed,
and only use the title for comparisons (ignoring the content),
use .reader.dedupe.once.title instead.
Entry user attributes are set as follows:
If any of the entries is read/important, the new entry will be read/important.
read_modified / important_modified
Set to the oldest modified of the entries with the same status as the new read/important.
entry tags
For each tag key:
collect all the values from the duplicate entries
if the new entry does not have the tag, set it to the first value
copy the remaining values to the new entry, using a key of the form
.reader.duplicate.N.of.TAG, where N is an integer and TAG is the tag keyOnly unique values are considered, such that
TAG,.reader.duplicate.1.of.TAG,.reader.duplicate.2.of.TAG… always have different values.
To reduce false negatives when detecting duplicates:
All comparisons are case-insensitive, with HTML tags, HTML entities, punctuation, and whitespace removed.
For entries with content of different lengths, only a prefix of common (smaller) length is used in comparison. (This is useful when one version of an entry has only the first paragraph of the article, but the other has the whole article.)
For entries with longer content (over ~48 words), approximate matching is used instead of an exact match (currently, Jaccard similarity of 4-grams).
To reduce false positives when detecting duplicates:
Titles must match exactly (after clean-up).
Both entries must have title and content.
Similarity thresholds are set relatively high, and higher for shorter content.
Changelog
Changed in version 2.3: Delete old duplicates instead of marking them as read / unimportant.
Changed in version 2.2: Reduce false negatives by using approximate content matching.
Changed in version 2.2: Make it possible to re-run the plugin for existing entries.
reader.mark_as_read
Mark added entries of specific feeds as read + unimportant if their title matches a regex.
To configure, set the make_reader_reserved_name('mark-as-read')
(by default, .reader.mark-as-read)
tag to something like:
{
"title": ["first-regex", "second-regex"]
}
Changelog
Changed in version 3.5: Don’t set read_modified and
important_modified anymore;
because important is now optional,
important = False is enough to mark an entry as unimportant.
Old unimportant entries will be migrated automatically.
Changed in version 2.7: Use the .reader.mark-as-read metadata for configuration.
Feeds using the old metadata, .reader.mark_as_read,
will be migrated automatically on update until reader 3.0.
Changed in version 2.4: Explicitly mark matching entries as unimportant.
reader.readtime
Calculate the read time for new/updated entries,
and store it as the .reader.readtime entry tag, with the format:
{'seconds': 1234}
The content used is that returned by get_content().
The read time for existing entries is backfilled as follows:
On the first
update_feeds()/update_feeds_iter()call:all feeds with
updates_disabledfalse are scheduled to be backfilledthe feeds selected to be updated are backfilled then
the feeds not selected to be updated will be backfilled the next time they are updated
all feeds with
updates_disabledtrue are backfilled, regardless of which feeds are selected to be updated
To prevent any feeds from being backfilled, set the
.reader.readtimeglobal tag to{'backfill': 'done'}.To schedule a feed to be backfilled on its next update, set the
.reader.readtimefeed tag to{'backfill': 'pending'}.
Changelog
Changed in version 3.1: Do not require additional dependencies.
Deprecate the readtime extra.
New in version 2.12.
reader.ua_fallback
Retry feed requests that get 403 Forbidden
with a different user agent.
Sometimes, servers blocks requests coming from reader based on the user agent. This plugin retries the request with feedparser’s user agent, which seems to be more widely accepted.
Servers/CDNs known to not accept the reader UA: Cloudflare, WP Engine.
Experimental plugins
reader also ships with a number of experimental plugins.
For these, the full entry point must be specified.
To use them from within Python code, use the entry point as a custom plugin:
>>> from reader._plugins import sqlite_releases
>>> reader = make_reader("db.sqlite", plugins=[sqlite_releases.init])
cli_status
Capture the stdout of a CLI command and add it as an entry to a special feed.
The feed URL is reader:status; if it does not exist, it is created.
The entry id is the command, without options or arguments:
('reader:status', 'command: update')
('reader:status', 'command: search update')
Entries are marked as read.
To load:
READER_CLI_PLUGIN='reader._plugins.cli_status.init_cli' \
python -m reader ...
preview_feed_list
If the feed to be previewed is not actually a feed, show a list of feeds linked from that URL (if any).
This plugin needs additional dependencies, use the unstable-plugins extra
to install them:
pip install reader[unstable-plugins]
To load:
READER_APP_PLUGIN='reader._plugins.preview_feed_list:init' \
python -m reader serve
Implemented for https://github.com/lemon24/reader/issues/150.
sqlite_releases
Create a feed out of the SQLite release history pages at:
Also serves as an example of how to write custom parsers.
This plugin needs additional dependencies, use the unstable-plugins extra
to install them:
pip install reader[unstable-plugins]
To load:
READER_PLUGIN='reader._plugins.sqlite_releases:init' \
python -m reader ...
timer
Measure Reader, Storage, and search
method calls, including time spent in iterables.
If loaded, the Web application will show per-request method statistics in the footer.
Once reader.timer.enable() is called,
the timing of each method call is collected in reader.timer.calls;
disable() clears the list of calls and stops collection:
>>> reader = make_reader('db.sqlite', plugins=[
... 'reader._plugins.timer:init_reader'
... ])
>>> reader.timer.enable()
>>> for _ in reader.get_entries(limit=500): pass
>>> for call in reader.timer.calls:
... print(f"{call.name:30} {call.time:9.6f}")
...
Reader.get_entries 0.304127
Storage.get_entries 0.290139
Storage.get_entries_page 0.159803
Storage.get_db 0.000008
Storage.get_entries_page 0.128641
Storage.get_db 0.000826
>>> print(reader.timer.format_stats())
len sum min avg max
Reader.get_entries 1 0.304 0.304 0.304 0.304
Storage.get_db 2 0.001 0.000 0.000 0.001
Storage.get_entries 1 0.290 0.290 0.290 0.290
Storage.get_entries_page 2 0.288 0.129 0.144 0.160
This plugin needs additional dependencies, use the unstable-plugins extra
to install them:
pip install reader[unstable-plugins]
Discontinued plugins
Following are experimental plugins that are not very useful anymore.
twitter
Prior to version 3.7, reader had a Twitter plugin; it was removed because it’s not possible to get tweets using the free API tier anymore.
However, the plugin used the internal Parser API in new and interesting ways – it mapped the multiple tweets in a thread to a single entry, and stored old tweets alongside the rendered HTML content to avoid retrieving them again when updating the thread/entry.
You can still find the code on GitHub: twitter.py.
tumblr_gdpr
Prior to version 3.7, reader had a plugin to accept Tumblr GDPR terms (between 2018 and 2020, Tumblr would redirect all new sessions to an “accept the terms of service” page, including machine-readable RSS feeds).
This plugin is a good example of how to set cookies on the Requests session used to retrieve feeds.
You can still find the code on GitHub: tumblr_gdpr.py.
Loading plugins from the CLI and the web application
There is experimental support of plugins in the CLI and the web application.
Warning
The plugin system/hooks are not stable yet and may change without any notice.
To load plugins, set the READER_PLUGIN environment variable to the plugin
entry point (e.g. package.module:entry_point); multiple entry points should
be separated by one space:
READER_PLUGIN='first.plugin:entry_point second_plugin:main' \
python -m reader some-command
For built-in plugins, it is enough to use the plugin name (reader.XYZ).
Note
make_reader() ignores the plugin environment variables.
To load web application plugins, set the READER_APP_PLUGIN environment variable.
To load CLI plugins (that customize the CLI),
set the READER_CLI_PLUGIN environment variable.