API to define a default template for the template mode

[youknowriad]

WordPress 5.8 will introduce a template mode in the post editor https://make.wordpress.org/core/2021/06/14/introducing-the-template-editor-in-wordpress-5-8/

That mode allows users to create block templates and assign them to posts and pages. A default starting template is used to repopulate newly created templates.

Ideally, themes should be able to define the content of the initial template. Let's try to provide an API to do so. This API should be able to scale to FSE themes as well.

The simplest solution might be to add a settings to the block_editor_settings_all filter as this can be provided in php and made translatable easily.

An alternative would be a file in the theme (convention) but since we don't want to add block-templates to themes yet, it seems premature for this option.

cc @TimothyBJacobs @aristath

[aristath]

Using the block_editor_settings_all filter would make sense...
The 1st thought that came to mind was introduce a block-template-default.html file, but the filter sounds more versatile, and it can still be used with a file using something like

add_filter( 'block_editor_settings_all', function( $settings ) {
    $settings['block_template'] = file_get_contents( get_theme_file_path( 'block-template-default.html' ) );
    return $settings;
});

so using the filter does not exclude using a file... it makes sense to do something like that since it leaves the door open for other future implementations

[youknowriad]

yes, that make sense maybe it should be named more something like default_block_template?

[aristath]

maybe it should be named more something like default_block_template?

Yes, that would make sense. Or even default_block_template_content if we want to be more verbose/accurate 👍