如何使用AngularJS调用php脚本中的特定函数？

I am using AngularJS to access a PHP script but I only want to call out a specific function. In the app.js script below the updatePost and deletePost function are called by a button click. I have already up broken the functions into separate files and used angular's http function to get them separately and they all worked fine but now I just want to store them in functions within the functions.php file but I am not sure how I can call them individually?I am using AngularJS to access a PHP script but