Add-ons

Add-ons provide ways to customize and automate the translation workflow. Admins can add and manage add-ons from the ManageAdd-ons menu of each respective translation project or component. Add-ons can be also installed site-wide in Management interface.

Hint

You can also configure add-ons using API, DEFAULT_ADDONS, or install_addon.

../_images/addons.webp

Events that trigger add-ons

Add-on installation

Triggered when add-on is being installed.

Component update

Triggered whenever a change happens in a component such as:

  • Strings are changed in the repository.

  • A string is added.

  • A new translation is added.

Daily

Triggered daily, but add-ons usually split the daily load between components depending on BACKGROUND_TASKS.

Repository post-add

Triggered just after the new translation is added and committed.

Repository post-commit

Triggered just after the changes are committed.

Repository post-push

Triggered just after the repository is pushed upstream.

Repository post-update

Triggered whenever new changes are pulled from the upstream repository.

Repository pre-commit

Triggered just before the changes are committed.

Repository pre-push

Triggered just before the repository is pushed upstream.

Repository pre-update

Triggered just before the repository update is attempted.

Storage post-load

Triggered when file is parsed by Weblate.

Unit post-save

Triggered just after the string is saved.

Unit pre-create

Triggered just after the newly created string is saved.

Built-in add-ons

Automatic translation

Add-on ID:

weblate.autotranslate.autotranslate

Configuration:

mode

Automatic translation mode

Available choices:

suggest – Add as suggestion

translate – Add as translation

fuzzy – Add as “Needing edit”

filter_type

Search filter

Please note that translating all strings will discard all existing translations.

Available choices:

all – All strings

nottranslated – Untranslated strings

todo – Unfinished strings

fuzzy – Strings marked for edit

check:inconsistent – Failing check: Inconsistent

check:translated – Failing check: Has been translated

auto_source

Source of automated translations

Available choices:

others – Other translation components

mt – Machine translation

component

Component

Enter slug of a component to use as source, keep blank to use all components in the current project.

engines

Machine translation engines

threshold

Score threshold

Triggers:

Add-on installation, Component update, Daily

Automatically translates strings using machine translation or other components.

JavaScript localization CDN

Added in version 4.2.

Add-on ID:

weblate.cdn.cdnjs

Configuration:

threshold

Translation threshold

Threshold for inclusion of translations.

css_selector

CSS selector

CSS selector to detect localizable elements.

cookie_name

Language cookie name

Name of cookie which stores language preference.

files

Extract strings from HTML files

List of filenames in current repository or remote URLs to parse for translatable strings.

Triggers:

Add-on installation, Daily, Repository post-commit, Repository post-update

Publishes translations into content delivery network for use in JavaScript or HTML localization.

Can be used to localize static HTML pages, or to load localization in the JavaScript code.

Generates a unique URL for your component you can include in HTML pages to localize them. See Translating HTML and JavaScript using Weblate CDN for more details.

Note

This add-on requires additional configuration on the Weblate server. LOCALIZE_CDN_PATH configures where generated files will be written (on a filesystem), and LOCALIZE_CDN_URL defines where they will be served (URL). Serving of the files is not done by Weblate and has to be set up externally (typically using a CDN service).

This add-on is configured on Hosted Weblate and serves the files via https://weblate-cdn.com/.

Remove blank strings

Added in version 4.4.

Add-on ID:

weblate.cleanup.blank

Configuration:

This add-on has no configuration.

Triggers:

Add-on installation, Repository post-commit, Repository post-update

Removes strings without a translation from translation files.

Use this to not have any empty strings in translation files (for example if your localization library displays them as missing instead of falling back to the source string).

Cleanup translation files

Add-on ID:

weblate.cleanup.generic

Configuration:

This add-on has no configuration.

Triggers:

Add-on installation, Repository post-update, Repository pre-commit

Update all translation files to match the monolingual base file. For most file formats, this means removing stale translation keys no longer present in the base file.

For formats containing additional content besides translation strings (such as HTML files, Windows RC files, or OpenDocument Format) this also brings the translation file in sync with the base file.

Add missing languages

Add-on ID:

weblate.consistency.languages

Configuration:

This add-on has no configuration.

Triggers:

Add-on installation, Daily, Repository post-add

Ensures a consistent set of languages is used for all components within a project.

Missing languages are checked once every 24 hours, and when new languages are added in Weblate.

Unlike most others, this add-on affects the whole project.

Hint

Auto-translate the newly added strings with Automatic translation.

Component discovery

Add-on ID:

weblate.discovery.discovery

Configuration:

match

Regular expression to match translation files against

file_format

File format

name_template

Customize the component name

base_file_template

Define the monolingual base filename

Leave empty for bilingual translation files.

new_base_template

Define the base file for new translations

Filename of file used for creating new translations. For gettext choose .pot file.

intermediate_template

Intermediate language file

Filename of intermediate translation file. In most cases this is a translation file provided by developers and is used when creating actual source strings.

language_regex

Language filter

Regular expression to filter translation files against when scanning for file mask.

copy_addons

Clone add-ons from the main component to the newly created ones

remove

Remove components for inexistent files

confirm

I confirm the above matches look correct

Triggers:

Add-on installation, Repository post-update

Automatically adds or removes project components based on file changes in the version control system.

The matching is done using regular expressions enabling complex configuration, but some knowledge is required to do so. Some examples for common use cases can be found in the add-on help section.

The regular expression to match translation files has to contain two named groups to match component and language. All named groups in the regular expression can be used as variables in the template fields.

You can use Django template markup in all filename fields, for example:

{{ component }}

Component filename match

{{ component|title }}

Component filename with upper case first letter

{{ path }}: {{ component }}

Custom match group from the regular expression

Once you hit Save, a preview of matching components will be presented, from where you can check whether the configuration actually matches your needs:

../_images/addon-discovery.webp

Component discovery examples

One folder per language

One folder per language containing translation files for components.

Regular expression:

(?P<language>[^/.]*)/(?P<component>[^/]*)\.po

Matching files:
  • cs/application.po

  • cs/website.po

  • de/application.po

  • de/website.po

Gettext locales layout

Usual structure for storing gettext PO files.

Regular expression:

locale/(?P<language>[^/.]*)/LC_MESSAGES/(?P<component>[^/]*)\.po

Matching files:
  • locale/cs/LC_MESSAGES/application.po

  • locale/cs/LC_MESSAGES/website.po

  • locale/de/LC_MESSAGES/application.po

  • locale/de/LC_MESSAGES/website.po

Complex filenames

Using both component and language name within filename.

Regular expression:

src/locale/(?P<component>[^/]*)\.(?P<language>[^/.]*)\.po

Matching files:
  • src/locale/application.cs.po

  • src/locale/website.cs.po

  • src/locale/application.de.po

  • src/locale/website.de.po

Repeated language code

Using language in both path and filename.

Regular expression:

locale/(?P<language>[^/.]*)/(?P<component>[^/]*)/(?P=language)\.po

Matching files:
  • locale/cs/application/cs.po

  • locale/cs/website/cs.po

  • locale/de/application/de.po

  • locale/de/website/de.po

Split Android strings

Android resource strings, split into several files.

Regular expression:

res/values-(?P<language>[^/.]*)/strings-(?P<component>[^/]*)\.xml

Matching files:
  • res/values-cs/strings-about.xml

  • res/values-cs/strings-help.xml

  • res/values-de/strings-about.xml

  • res/values-de/strings-help.xml

Matching multiple paths

Multi-module Maven project with Java properties translations.

Regular expression:

(?P<originalHierarchy>.+/)(?P<component>[^/]*)/src/main/resources/ApplicationResources_(?P<language>[^/.]*)\.properties

Component name:

{{ originalHierarchy }}: {{ component }}

Matching files:
  • parent/module1/submodule/src/main/resources/ApplicationResources_fr.properties

  • parent/module1/submodule/src/main/resources/ApplicationResource_es.properties

  • parent/module2/src/main/resources/ApplicationResource_de.properties

  • parent/module2/src/main/resources/ApplicationResource_ro.properties

Hint

Component discovery add-on uses Weblate internal URLs. It’s a convenient way to share VCS setup between multiple components. Linked components use the local repository of the main component set up by filling weblate://project/main-component into the Source code repository field (in ManageSettingsVersion control system) of each respective component. This saves time with configuration and system resources too.

Bulk edit

Add-on ID:

weblate.flags.bulk

Configuration:

q

Query

state

State to set

Available choices:

-1 – Do not change

10 – Needs editing

20 – Translated

30 – Approved

add_flags

Translation flags to add

remove_flags

Translation flags to remove

add_labels

Labels to add

remove_labels

Labels to remove

Triggers:

Add-on installation, Component update

Bulk edit flags, labels, or states of strings.

Examples:

Label new strings automatically

Search query

NOT has:label

Labels to add

recent

Marking all App store metadata files changelog strings read-only

Search query

language:en AND key:changelogs/

Translation flags to add

read-only

Marking certain strings read-only

Search query

source:r"^\`\`[.a-zA-Z0-9_-]*\`\`$" AND language:en

Translation flags to add

read-only

Flag unchanged translations as “Needs editing”

Add-on ID:

weblate.flags.same_edit

Configuration:

This add-on has no configuration.

Triggers:

Unit pre-create

Whenever a new translatable string is imported from the VCS and it matches a source string, it is flagged as needing editing in Weblate. Especially useful for file formats that include source strings for untranslated strings.

Hint

You might also want to tighthen the Unchanged translation check by adding strict-same flag to Translation flags.

Flag new source strings as “Needs editing”

Add-on ID:

weblate.flags.source_edit

Configuration:

This add-on has no configuration.

Triggers:

Unit pre-create

Whenever a new source string is imported from the VCS, it is flagged as needing editing in Weblate. This way you can easily filter and edit source strings written by the developers.

Flag new translations as “Needs editing”

Add-on ID:

weblate.flags.target_edit

Configuration:

This add-on has no configuration.

Triggers:

Unit pre-create

Whenever a new translatable string is imported from the VCS, it is flagged as needing editing in Weblate. This way you can easily filter and edit translations created by the developers.

Fill read-only strings with source

Added in version 4.18.

Add-on ID:

weblate.generate.fill_read_only

Configuration:

This add-on has no configuration.

Triggers:

Add-on installation, Component update, Daily

Fills in translation of read-only strings with source string.

Statistics generator

Add-on ID:

weblate.generate.generate

Configuration:

filename

Name of generated file

template

Content of generated file

Triggers:

Repository pre-commit

Generates a file containing detailed info about the translation status.

You can use a Django template in both filename and content, see Template markup for a detailed markup description.

For example generating a summary file for each translation:

Name of generated file

locale/{{ language_code }}.json

Content
{
   "language": "{{ language_code }}",
   "strings": "{{ stats.all }}",
   "translated": "{{ stats.translated }}",
   "last_changed": "{{ stats.last_changed }}",
   "last_author": "{{ stats.last_author }}",
}

See also

Template markup

Prefill translation with source

Added in version 4.11.

Add-on ID:

weblate.generate.prefill

Configuration:

This add-on has no configuration.

Triggers:

Add-on installation, Component update, Daily

Fills in translation strings with source string.

All untranslated strings in the component will be filled with the source string, and marked as needing edit. Use this when you can not have empty strings in the translation files.

Pseudolocale generation

Added in version 4.5.

Add-on ID:

weblate.generate.pseudolocale

Configuration:

source

Source strings

target

Target translation

All strings in this translation will be overwritten

prefix

Fixed string prefix

var_prefix

Variable string prefix

suffix

Fixed string suffix

var_suffix

Variable string suffix

var_multiplier

Variable part multiplier

How many times to repeat the variable part depending on the length of the source string.

include_readonly

Include read-only strings

Triggers:

Add-on installation, Component update, Daily

Generates a translation by adding prefix and suffix to source strings automatically.

Pseudolocales are useful to find strings that are not prepared for localization. This is done by altering all translatable source strings to make it easy to spot unaltered strings when running the application in the pseudolocale language.

Finding strings whose localized counterparts might not fit the layout is also possible.

Using the variable parts makes it possible to look for strings which might not fit into the user interface after the localization - it extends the text based on the source string length. The variable parts are repeated by length of the text multiplied by the multiplier. For example Hello world with variable suffix _ and variable multiplier of 1 becomes Hello world___________ - the suffix is repeated once for each character in the source string.

The strings will be generated using following pattern:

Fixed string prefix Variable string prefix Source string Variable string suffix Fixed string suffix

Hint

You can use real languages for testing, but there are dedicated pseudolocales available in Weblate - en_XA and ar_XB.

Hint

You can use this add-on to start translation to a new locale of an existing language or similar language. Once you add the translation to the component, follow to the add-on. Example: If you have fr and want to start fr_CA translation, simply set fr as the source, fr_CA as the target, and leave the prefix and suffix blank.

Uninstall the add-on once you have the new translation filled to prevent Weblate from changing the translations made after the copying.

Contributors in comment

Add-on ID:

weblate.gettext.authors

Configuration:

This add-on has no configuration.

Triggers:

Repository pre-commit

Updates the comment part of the PO file header to include contributor names and years of contributions.

The PO file header will look like this:

# Michal Čihař <michal@weblate.org>, 2012, 2018, 2019, 2020.
# Pavel Borecki <pavel@example.com>, 2018, 2019.
# Filip Hron <filip@example.com>, 2018, 2019.
# anonymous <noreply@weblate.org>, 2019.

Update ALL_LINGUAS variable in the “configure” file

Add-on ID:

weblate.gettext.configure

Configuration:

This add-on has no configuration.

Triggers:

Add-on installation, Daily, Repository post-add

Updates the ALL_LINGUAS variable in configure, configure.in or any configure.ac files, when a new translation is added.

Customize gettext output

Add-on ID:

weblate.gettext.customize

Configuration:

width

Long lines wrapping

By default gettext wraps lines at 77 characters and at newlines. With the –no-wrap parameter, wrapping is only done at newlines.

Available choices:

77 – Wrap lines at 77 characters and at newlines (xgettext default)

65535 – Only wrap lines at newlines (like ‘xgettext –no-wrap’)

-1 – No line wrapping

Triggers:

Storage post-load

Allows customization of gettext output behavior, for example line wrapping.

It offers the following options:

  • Wrap lines at 77 characters and at newlines

  • Only wrap lines at newlines

  • No line wrapping

Note

By default gettext wraps lines at 77 characters and at newlines. With the --no-wrap parameter, wrapping is only done at newlines.

Update LINGUAS file

Add-on ID:

weblate.gettext.linguas

Configuration:

This add-on has no configuration.

Triggers:

Add-on installation, Daily, Repository post-add

Updates the LINGUAS file when a new translation is added.

Generate MO files

Add-on ID:

weblate.gettext.mo

Configuration:

path

Path of generated MO file

If not specified, the location of the PO file will be used.

fuzzy

Include strings needing editing

Strings needing editing (fuzzy) are typically not ready for use as translations.

Triggers:

Repository pre-commit

Automatically generates a MO file for every changed PO file.

The location of the generated MO file can be customized and the field for it uses Template markup.

Note

If a translation is removed, its PO file will be deleted from the repository, but the MO file generated by this add-on will not. The MO file must be removed from the upstream manually.

Update PO files to match POT (msgmerge)

Add-on ID:

weblate.gettext.msgmerge

Configuration:

previous

Keep previous msgids of translated strings

no_location

Remove locations of translated strings

fuzzy

Use fuzzy matching

Triggers:

Add-on installation, Repository post-update

Updates all PO files (as configured by File mask) to match the POT file (as configured by Template for new translations) using msgmerge.

Most msgmerge command-line options can be set up through the add-on configuration.

Squash Git commits

Add-on ID:

weblate.git.squash

Configuration:

squash

Commit squashing

Available choices:

all – All commits into one

language – Per language

file – Per file

author – Per author

append_trailers

Append trailers to squashed commit message

Trailer lines are lines that look similar to RFC 822 e-mail headers, at the end of the otherwise free-form part of a commit message, such as ‘Co-authored-by: …’.

commit_message

Commit message

This commit message will be used instead of the combined commit messages from the squashed commits.

Triggers:

Add-on installation, Repository post-commit

Squash Git commits prior to pushing changes.

Git commits can be squashed prior to pushing changes in one of the following modes:

  • All commits into one

  • Per language

  • Per file

  • Per author

Original commit messages are kept, but authorship is lost unless Per author is selected, or the commit message is customized to include it.

The original commit messages can optionally be overridden with a custom commit message.

Trailers (commit lines like Co-authored-by: ) can optionally be removed from the original commit messages and appended to the end of the squashed commit message. This also generates proper Co-authored-by: credit for every translator.

Customize JSON output

Add-on ID:

weblate.json.customize

Configuration:

sort_keys

Sort JSON keys

indent

JSON indentation

style

JSON indentation style

Available choices:

spaces – Spaces

tabs – Tabs

Triggers:

Storage post-load

Allows adjusting JSON output behavior, for example indentation or sorting.

Format the Java properties file

Add-on ID:

weblate.properties.sort

Configuration:

case_sensitive

Enable case-sensitive key sorting

Triggers:

Repository pre-commit

Formats and sorts the Java properties file.

  • Consolidates newlines to Unix ones.

  • Uppercase formatting of Unicode escape sequences (in case they are present).

  • Strips blank lines and comments.

  • Sorts the strings by the keys.

  • Drops duplicate strings.

Stale comment removal

Add-on ID:

weblate.removal.comments

Configuration:

age

Days to keep

Triggers:

Add-on installation, Daily

Set a timeframe for removal of comments.

This can be useful to remove old comments which might have become outdated. Use with care as comments getting old does not mean they have lost their importance.

Stale suggestion removal

Add-on ID:

weblate.removal.suggestions

Configuration:

age

Days to keep

votes

Voting threshold

Threshold for removal. This field has no effect with voting turned off.

Triggers:

Add-on installation, Daily

Set a timeframe for removal of suggestions.

Can be very useful in connection with suggestion voting (see Peer review) to remove suggestions which don’t receive enough positive votes in a given timeframe.

Update RESX files

Add-on ID:

weblate.resx.update

Configuration:

This add-on has no configuration.

Triggers:

Add-on installation, Repository post-update

Update all translation files to match the monolingual upstream base file. Unused strings are removed, and new ones added as copies of the source string.

Hint

Use Cleanup translation files if you only want to remove stale translation keys.

Customize XML output

Added in version 4.15.

Add-on ID:

weblate.xml.customize

Configuration:

closing_tags

Include closing tag for blank XML tags

Triggers:

Storage post-load

Allows adjusting XML output behavior, for example closing tags.

Customize YAML output

Add-on ID:

weblate.yaml.customize

Configuration:

indent

YAML indentation

width

Long lines wrapping

Available choices:

80 – Wrap lines at 80 chars

100 – Wrap lines at 100 chars

120 – Wrap lines at 120 chars

180 – Wrap lines at 180 chars

65535 – No line wrapping

line_break

Line breaks

Available choices:

dos – DOS (\r\n)

unix – UNIX (\n)

mac – MAC (\r)

Triggers:

Storage post-load

Allows adjusting YAML output behavior, for example line-length or newlines.

Customizing list of add-ons

The list of add-ons is configured by WEBLATE_ADDONS. To add another add-on, simply include the absolute class name in this setting.

Writing add-on

You can write your own add-ons too, create a subclass of weblate.addons.base.BaseAddon to define the add-on metadata, and then implement a callback to do the processing.

Executing scripts from add-on

Add-ons can also be used to execute external scripts. This used to be integrated in Weblate, but now you have to write some code to wrap your script with an add-on.

# Copyright © Michal Čihař <michal@weblate.org>
#
# SPDX-License-Identifier: GPL-3.0-or-later

"""Example pre commit script."""

from django.utils.translation import gettext_lazy

from weblate.addons.events import AddonEvent
from weblate.addons.scripts import BaseScriptAddon


class ExamplePreAddon(BaseScriptAddon):
    # Event used to trigger the script
    events: set[AddonEvent] = {
        AddonEvent.EVENT_PRE_COMMIT,
    }
    # Name of the addon, has to be unique
    name = "weblate.example.pre"
    # Verbose name and long description
    verbose = gettext_lazy("Execute script before commit")
    description = gettext_lazy("This add-on executes a script.")

    # Script to execute
    script = "/bin/true"
    # File to add in commit (for pre commit event)
    # does not have to be set
    add_file = "po/{{ language_code }}.po"

For installation instructions see Custom quality checks, add-ons and auto-fixes.

The script is executed with the current directory set to the root of the VCS repository for any given component.

Additionally, the following environment variables are available:

WL_VCS

Version control system used.

WL_REPO

Upstream repository URL.

WL_PATH

Absolute path to VCS repository.

WL_BRANCH

Repository branch configured in the current component.

WL_FILEMASK

File mask for current component.

WL_TEMPLATE

Filename of template for monolingual translations (can be empty).

WL_NEW_BASE

Filename of the file used for creating new translations (can be empty).

WL_FILE_FORMAT

File format used in current component.

WL_LANGUAGE

Language of currently processed translation (not available for component-level hooks).

WL_PREVIOUS_HEAD

Previous HEAD after update (only available after running the post-update hook).

WL_COMPONENT_SLUG

Component slug used to construct URL.

WL_PROJECT_SLUG

Project slug used to construct URL.

WL_COMPONENT_NAME

Component name.

WL_PROJECT_NAME

Project name.

WL_COMPONENT_URL

Component URL.

WL_ENGAGE_URL

Project engage URL.

Post-update repository processing

Can be used to update translation files when the VCS upstream source changes. To achieve this, please remember Weblate only sees files committed to the VCS, so you need to commit changes as a part of the script.

For example with Gulp you can do it using following code:

#! /bin/sh
gulp --gulpfile gulp-i18n-extract.js
git commit -m 'Update source strings' src/languages/en.lang.json

Pre-commit processing of translations

Use the commit script to automatically change a translation before it is committed to the repository.

It is passed as a single parameter consisting of the filename of a current translation.

Add-on activity logging

Add-on activity log keeps track of the add-on execution and can be used to keep track of add-on activity.

The logs can be pruned after a certain time interval by configuring the ADDON_ACTIVITY_LOG_EXPIRY.