Bug: [CURLRequest] Multiple HTTP 100 return by API

[PhpEssential]

PHP Version

8.1

CodeIgniter4 Version

4.4.2

CodeIgniter4 Installation Method

Composer (using codeigniter4/appstarter)

Which operating systems have you tested for this bug?

Windows, Linux

Which server did you use?

apache

Database

No response

What happened?

When I call API built with a Flask server, this one return these headers:

HTTP/1.1 100 Continue

HTTP/1.1 100 Continue

HTTP/1.1 500 INTERNAL SERVER ERROR
Server: Werkzeug/2.2.3 Python/3.7.16
Date: Tue, 19 Dec 2023 21:30:20 GMT
Content-Type: application/json
Content-Length: 403
Access-Control-Allow-Origin: *
Connection: close

In this case the CURLRequest class doesn't parse correctlly the headers

Steps to Reproduce

Make POST API with Flask 2.2.5 in debug mode and call it via CURLRequest

Expected Output

In this case status code should be 500 not 100

Anything else?

Just change this:

        if (strpos($output, 'HTTP/1.1 100 Continue') === 0) {

By this:

        while (strpos($output, 'HTTP/1.1 100 Continue' . $breakString) === 0) {

at line 392

For others who have the problem, actually I overwrite the class and specially the function send in my project and instanciate it via this function in Config\Service:

    public static function curlrequest($options = [], ResponseInterface $response = null, App $config = null, $getShared = false) {
        if ($getShared) {
            return static::getSharedInstance('curlrequest');
        }
        
        if(empty($config)) {
            $config = config(App::class);
        }
        return new CURLRequest($config, new URI((empty($options['baseURI']) ? null : $options['baseURI'])), $response, $options);
     }

[kenjis]

Your fix makes an existing test fail.

How about this?

--- a/system/HTTP/CURLRequest.php
+++ b/system/HTTP/CURLRequest.php
@@ -389,7 +389,7 @@ class CURLRequest extends OutgoingRequest
         // Set the string we want to break our response from
         $breakString = "\r\n\r\n";
 
-        if (strpos($output, 'HTTP/1.1 100 Continue') === 0) {
+        while (strpos($output, 'HTTP/1.1 100 Continue') === 0) {
             $output = substr($output, strpos($output, $breakString) + 4);
         }
 

[ping-yee]

Off topic, I have prepared the reproduction code and set up the flask server.
But how can I obtain the header information?

HTTP/1.1 100 Continue

HTTP/1.1 100 Continue

HTTP/1.1 500 INTERNAL SERVER ERROR
Server: Werkzeug/2.2.3 Python/3.7.16
Date: Tue, 19 Dec 2023 21:30:20 GMT
Content-Type: application/json
Content-Length: 403
Access-Control-Allow-Origin: *
Connection: close

[kenjis]

$ curl -v https://codeigniter.com

[ping-yee]

@kenjis I've reproduced the issue and the change can work.
I sent the PR #8466

[kenjis]

@ping-yee Great!

[PhpEssential]

Ok thanks ! In my case the flask call another api, maybe it's the way to reproduce