of course, the API you requested is returned to you. The API you requested calculates the length of the json file array. If you request this API, the subscript of the json list, the corresponding value of the subscript and the length of the json list are returned to you.

the php you requested

check whether the data received by Network in browser F12 is the data of your first graph--

since the request is sent to a php file, the return result is the php-controlled ~

background interface to receive the request, get the data from the database or other systems, and then convert it to JSON format. Returned by the response client. Item may be an object or dictionary in the background code, and message,name is its attribute or key-value pair