Developing new Plugins

If you want to write a plugin, it’s a very good idea to checkout existing plugins. A good starting point for example is the Portal Plugin.

Also make sure to check out the cookiecutter-flaskbb-plugin project, which is a cookiecutter template which helps you to create new plugins.

For example, the structure of a plugin could look like this:

|-- my_plugin
    |-- static
    |   |-- style.css
    |-- templates
        |-- myplugin.html
    |-- migrations


FlaskBB Plugins are usually following the naming scheme of flaskbb-plugin-YOUR_PLUGIN_NAME which should make them better distinguishable from other PyPI distributions.

A proper plugin should have at least put the following metadata into the file.

    name="flaskbb-plugin-YOUR_PLUGIN_NAME",  # name on PyPI
    packages=["your_package_name"],  # name of the folder your plugin is located in
    url=<url to your project>,
    license=<your license>,
    author_email=<your email>,
    description=<your short description>,

        'flaskbb_plugin': [
            'unique_name_of_plugin = your_package_name.pluginmodule',  # most important part

The most important part here is the entry_point. Here you tell FlaskBB the unique name of your plugin and where your plugin module is located inside your project. Entry points are a feature that is provided by setuptools. FlaskBB looks up the flaskbb_plugin entrypoint to discover its plugins. Have a look at the setup script documentation and the sample file to get a better idea what the file is all about it.

For a full example, checkout the Portal Plugin.


Plugins can create settings which integrate with the ‘Settings’ tab of the Admin Panel.

The settings are stored in a dictionary with a given structure. The name of the dictionary must be SETTINGS and be placed in the plugin module.

The structure of the SETTINGS dictionary is best explained via an example:

    # This key has to be unique across FlaskBB.
    # Using a prefix is recommended.
    'forum_ids': {

        # Default Value. The type of the default value depends on the
        # SettingValueType.
        'value': [1],

        # The Setting Value Type.
        'value_type': SettingValueType.selectmultiple,

        # The human readable name of your configuration variable
        'name': "Forum IDs",

        # A short description of what the settings variable does
        'description': ("The forum ids from which forums the posts "
                        "should be displayed on the portal."),

        # extra stuff like the 'choices' in a select field or the
        # validators are defined in here
        'extra': {"choices": available_forums, "coerce": int}
Available Setting Value Types
Setting Value Type Parsed & Saved As
SettingValueType.string str
SettingValueType.integer int
SettingValueType.float float
SettingValueType.boolean bool list
SettingValueType.selectmultiple list
Available Additional Options via the extra Keyword
Options Applicable Types Description
min string, integer, float Optional. The minimum required length of the setting value. If used on a numeric type, it will check the minimum value.
max string, integer, float Optional. The maximum required length of the setting value. If used on a numeric type, it will check the maximum value.
choices select, selectmultiple Required. A callable which returns a sequence of (value, label) pairs.
coerce select, selectmultiple Optional. Coerces the select values to the given type.

Validating the size of the integer/float and the length of the string fields is also possible via the min and max keywords:

'recent_topics': {
    'extra': {"min": 1},

The select and selectmultiple fields have to provide a callback which lists all the available choices. This is done via the choices keyword. In addition to that they can also specify the coerce keyword which will coerce the input value into the specified type.:

'forum_ids': {
    'extra': {"choices": available_forums, "coerce": int}

For more information see the Settings chapter.