Hooks

Hooks are a way for one piece of code to interact/modify another piece of code at specific, pre-defined spots.

There are two types of hooks: Actions and Filters. To use either, you need to write a custom function known as a Callback, and then register it with a WordPress hook for a specific action or filter.

Actions

Actions allow you to add data or change how WordPress operates. Actions will run at a specific point in the execution of plugin. Callback functions for an Action do not return anything back to the calling Action hook.

remote_data_blocks_loaded

This action fires when Remote Data Blocks is fully loaded and ready for use. Plugins that depend on Remote Data Blocks should use this hook to defer their initialization until Remote Data Blocks is fully loaded.

function my_plugin_init() {
	// Initialize your plugin that depends on Remote Data Blocks here
	// All Remote Data Blocks classes and functionality are now available
}

if ( defined( 'REMOTE_DATA_BLOCKS__LOADED' ) ) {
	// Immediately init the plugin since remote data blocks is already loaded
	my_plugin_init()
} else {
	// Defer the init until the remote data block is loaded
	add_action( 'remote_data_blocks_loaded', 'my_plugin_init' );
}

remote_data_blocks_log

If you want to send debugging information to another source besides Query Monitor, use the remote_data_blocks_log action.

function custom_log( string $namespace, string $level, string $message, array $context ): void {
    // Send the log to a custom destination.
}
add_action( 'remote_data_blocks_log', 'custom_log', 10, 4 );

Filters

Filters give you the ability to change data during the execution of the plugin. Callback functions for Filters will accept a variable, modify it, and return it. They are meant to work in an isolated manner, and should never have side effects such as affecting global variables and output.

remote_data_blocks_register_example_block

Filter whether to register the included example API block (“Conference Event”) (default: true).

add_filter( 'remote_data_blocks_register_example_block', '__return_false' );

remote_data_blocks_allowed_url_schemes

Filter the allowed URL schemes for this request. Only HTTPS is allowed by default, but it might be useful to relax this restriction in local environments.

function custom_allowed_url_schemes( array $allowed_url_schemes, HttpQueryInterface $query ): array {
	// Modify the allowed URL schemes.
	return $allowed_url_schemes;
}
add_filter( 'remote_data_blocks_allowed_url_schemes', 'custom_allowed_url_schemes', 10, 2 );

remote_data_blocks_pagination_query_var_name

Filter the query variable name used for pagination (default: rdb-pagination).

function custom_pagination_query_var_name(): string {
	return 'paginate';
}
add_filter( 'remote_data_blocks_pagination_query_var_name', 'custom_pagination_query_var_name', 10, 0 );

remote_data_blocks_request_details

Filter the request details (method, options, url) before the HTTP request is dispatched.

function custom_request_details( array $request_details, HttpQueryInterface $query, array $input_variables ): array {
	// Modify the request details.
	return $request_details;
}
add_filter( 'remote_data_blocks_request_details', 'custom_request_details', 10, 3 );

remote_data_blocks_query_input_variables

Filter the query input variables prior to query execution. This filter is useful for modifying the input variables for the current page-load, e.g., by pulling in data from query variables or other context. See Overrides for more information.

add_filter( 'remote_data_blocks_query_input_variables', function ( array $input_variables, array $enabled_overrides, string $block_name, array $block_context ): array {
	if ( true === in_array( 'my_override', $enabled_overrides, true ) ) {
		$override_value = get_query_var( 'override_id' );

		if ( ! empty( $override_value ) ) {
			$input_variables['id'] = $override_value;
		}
	}

	return $input_variables;
}, 10, 4 );

Keep in mind that modifying query input variables will affect the object cache key used for query execution. This could result in a cache miss.

remote_data_blocks_query_response

Filter the query response just after query execution. This filter is useful for modifying the query response for the current page-load, e.g., by pulling in data from query variables or other context. See Overrides for more information.

add_filter( 'remote_data_blocks_query_response', function ( array $query_response, array $enabled_overrides, string $block_name, array $block_context ): array {
	if ( true === in_array( 'alternate_date_format', $enabled_overrides, true ) ) {
		$query_response['results'] = array_map( function ( array $result ) {
			$date = new DateTime( $result['date'] );
			$result['date'] = $date->format( 'Y F d' );
			return $result;
		}, $query_response['results'] );
	}

	return $input_variables;
}, 10, 4 );

The result of this filter is not cached, and will run for every block binding.

remote_data_blocks_query_response_metadata

Filter the query response metadata, which are available as targets for inline bindings. In most cases, it is better to provide a custom query class and override the get_response_metadata method, but this filter is available in case that is not possible.

function custom_query_response_metadata( array $metadata, HttpQueryInterface $query, array $input_variables ): array {
	// Modify the response metadata.
	return $metadata;
}
add_filter( 'remote_data_blocks_query_response_metadata', 'custom_query_response_metadata', 10, 3 );

Additional docs