Request and response handling in Wordpress - Step-by-Step Execution

Concept Flow - Request and response handling

User sends HTTP request

↓

WordPress receives request

↓

Parse URL and determine action

↓

Load plugins and themes

↓

Run hooks and filters

↓

Generate response content

↓

Send HTTP response back to user

This flow shows how WordPress handles a web request from the user, processes it, and sends back a response.

Execution Sample

Wordpress

<?php
add_action('init', function() {
  if ($_SERVER['REQUEST_METHOD'] === 'POST') {
    echo 'Form submitted';
  } else {
    echo 'Show form';
  }
});

This code checks if the request is a POST and outputs a message accordingly.

Execution Table

Step	Request Method	Condition	Action	Output
1	GET	Is POST?	No	Show form
2	POST	Is POST?	Yes	Form submitted
3	PUT	Is POST?	No	Show form
4	Exit	No more requests	Stop	End of handling

💡 No more requests to process, so WordPress stops handling.

Variable Tracker

Variable	Start	After Step 1	After Step 2	After Step 3	Final
$_SERVER['REQUEST_METHOD']	GET	GET	POST	PUT	PUT
Condition (Is POST?)	N/A	False	True	False	False
Output	N/A	Show form	Form submitted	Show form	Show form

Key Moments - 2 Insights

Why does the output change when the request method changes?

Because the code checks if the request method is POST (see execution_table rows 1-3). If true, it outputs 'Form submitted'; otherwise, it outputs 'Show form'.

What happens if the request method is neither GET nor POST?

The condition 'Is POST?' is false, so the output defaults to 'Show form' as shown in execution_table row 3.

Visual Quiz - 3 Questions

Look at the execution table, what is the output at step 2 when the request method is POST?

A No output

B Show form

C Form submitted

D Error

💡 Hint

Check the 'Output' column in execution_table row 2.

At which step does the condition 'Is POST?' evaluate to false?

A Step 2

B Step 1

C Step 4

D None

💡 Hint

Look at the 'Condition' column in execution_table rows 1 and 3.

If the request method changed to PUT, what would the output be according to the variable tracker?

A Show form

B Form submitted

C No output

D Error

💡 Hint

See the 'Output' value after step 3 in variable_tracker.

Concept Snapshot

WordPress handles requests by checking the HTTP method.
Use hooks like 'init' to run code on each request.
Check $_SERVER['REQUEST_METHOD'] to detect POST or GET.
Output content based on request type.
Response is sent back after processing.

Full Transcript

In WordPress, when a user sends a request, WordPress receives it and parses the URL to decide what to do. It loads plugins and themes, runs hooks and filters, then generates the response content. For example, using the 'init' hook, you can check if the request method is POST or GET by looking at $_SERVER['REQUEST_METHOD']. If it's POST, you might show a message like 'Form submitted'; if not, you show 'Show form'. This decision happens every time WordPress handles a request. The output depends on the request method. If the method is something else like PUT, the code treats it like GET and shows the form. This flow ensures WordPress responds correctly to different request types.