Use liveQuery to send data from the app to the server

/**
* WP-AppKit has no webservice dedicated to data update yet (this is one of the things on our roadmap).
* For now a workaround is to used the "liveQuery" webservice that was designed to retrieve custom
* content from server but can also work to update data.
* 
* The example here shows how to use liveQuery to send data from the app to the server 
* and handle this data on server side.
*
* The App.liveQuery() webservice used here is pretty convenient to handle any custom request from app to server. 
* We haven't found time to write doc about it yet but we have hope it will come soon ;)
*/

//In functions.js or custom js module in your app theme:
//Send data to the server using the "liveQuery" webservice:
// "my_data" can for example be a JSON Object comming from a form submission in the app
function sendMyDataToServer( my_data ) {
	
	//Define your custom query, that you will retrieve on server side
	//using the 'wpak_live_query' hook:
	var query_args = {
		my_action: 'my_livequery_action',
		my_data: my_data
	};

	//Define query options:
	var options = {
		auto_interpret_result: false, //This is to tell WPAK that you're doing your own custom query
		success: function( answer ) { //The meta update webservice call went ok
			if ( answer.my_result.ok === 1 ) {
				//Everything went ok. Display some success feedback to the user.
				console.log( 'LiveQuery action went well!', answer.my_result );
			} else {
				//An error occured in the server's liveQuery handler.
				//Display an error feedback to the user.
				console.log( 'LiveQuery action error: ', answer.my_result.error );
			}
		},
		error: function( error ) {
			//This is if the web service ajax call failed (no network)
			//Display an error feedback to the user.
			console.log( 'LiveQuery ajax failed', error );
		}
	};

	//Send our meta update query to the server:
	App.liveQuery( query_args, options );
}

//Server side
//Handle on PHP side the liveQuery call made in the app:
//(To put in a php file created in WP-AppKit theme's "php" folder)
add_filter( 'wpak_live_query', 'handle_my_live_query', 10, 2 );
function handle_my_live_query( $service_answer, $query_params ) {
	//$query_params contains what was passed in liveQuery's "query_args"
	
	//Check that the 'my_action' action set on app side is called:
	if ( isset( $query_params['my_action'] ) && $query_params['my_action'] === 'my_livequery_action' ) {
		
		//Prepare your custom answer:
		$result = array( 'ok' => 0, 'error' => '', 'my_feedback_data' => '' );
		
		//Check passed data:
		if ( !empty( $query_params['my_data'] ) ) {
			
			$sent_data = $query_params['my_data'];
			
			//Update our meta:
			if ( some_check_on_my_data( $sent_data )  ) {
				
				//Do what you need with $sent_data...

				//If everything went ok, set webservice answer to ok = 1:
				$result['ok'] = 1;
				
				//You can add any custom feedback data to the $result array sent
				//back to the app:
				$result['my_feedback_data'] = 'Everything went well :)';
				
			} else {
				$result['error'] = 'my-error';
			}
			
		} else {
			$result['error'] = 'no-data';
		}
		
		//Add your result to the web service answer:
		$service_answer['my_result'] = $result;
	}
	
	return $service_answer;
}