Can i use init hook for API purpose?

Question

My question title might be little confuse. Here is the scenario, For example: I am giving an API service from my wordpress site.

Using it others can know few information. Like if they send a User ID in query URL then i'll send them user phone number.

For Example: If they access the site with www.example.com/?cuid=23

Now on init hook i'll check if cuid is present in $_GET variable, if it is present then i'll get phone number and die the function with phone number. Since init hook is the earliest hook i choose to use it.

function tell_phone_num(){
         if(isset($_GET['cuid'])){
         //some one wants the service 
          //I'll get the phone number and show it -> $user_phone
         //setting response format, like json etc
          die($user_phone);
          }
}
add_action('init','tell_phone_num');

This works fine. When site is accessed with cuid then only this function will work.

This is just an example but phone number is not my real information. I don't need authentication because the information i am giving in are not sensitive.

Here is my question. Is this correct way to do or should I do some other best practice method.

Answer 1

If you want a more user-friendly URL structure, you could add a rewrite endpoint.

This will add the rules for and intercept requests to /my-api/:

function wpd_add_api_endpoint() {
    add_rewrite_endpoint( 'my-api', EP_ROOT );
}
add_action( 'init', 'wpd_add_api_endpoint' );

function wpd_api_request( $request ){
    if( isset( $request->query_vars['my-api'] ) ){

        // $request->query_vars['my-api'] is a string containing everything after your url slug
        // convert it to array
        $parts = explode( '/', $request->query_vars['my-api'] );

        echo '<pre>';
        print_r( $parts );
        echo '</pre>';

        die;
    }
}
add_action( 'parse_request', 'wpd_api_request' );

After you flush rules, try a request like:

http://example.com/my-api/something/else/123/4,5,6/&7

Which will output:

Array
(
    [0] => something
    [1] => else
    [2] => 123
    [3] => 4,5,6
    [4] => &7
)

Answer 2

Yes, init is good for this purpose. In codex is written:

init is useful for intercepting $_GET or $_POST triggers.