PHP_curl loose content-length on redirect - php

Question

I'm trying to make a request to payment processing page. This requires authorization, which takes place through a set of redirects. In the second step, I get "411 Length Required" error, which means that content-length was lost along the way. Indeed, I cannot see it in the log. What can be done here? Change tool (programming language)?
CURLOPT_VERBOSE:
* Trying xxx.xxx.xxx.xxx...
* TCP_NODELAY set
* Connected to api.dev.example.com (188.186.236.44) port 443 (#0)
* ALPN, offering http/1.1
* successfully set certificate verify locations:
* CAfile: /etc/ssl/certs/ca-certificates.crt
CApath: /etc/ssl/certs
* SSL connection using TLSv1.2 / ECDHE-RSA-AES256-GCM-SHA384
* ALPN, server accepted to use http/1.1
* Server certificate:
* subject: OU=Domain Control Validated; OU=PositiveSSL Wildcard; CN=*.dev.example.com
* start date: Apr 27 00:00:00 2019 GMT
* expire date: Apr 26 23:59:59 2021 GMT
* subjectAltName: host "api.dev.example.com" matched cert's "*.dev.example.com"
* issuer: C=GB; ST=Greater Manchester; L=Salford; O=Sectigo Limited; CN=Sectigo RSA Domain Validation Secure Server CA
* SSL certificate verify ok.
> POST /p2p/v2/payer HTTP/1.1
Host: api.dev.example.com
Content-Type: application/x-www-form-urlencoded
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8
Content-Length: 224
* upload completely sent off: 224 out of 224 bytes
< HTTP/1.1 302 Found
< Server: nginx
< Date: Mon, 13 Jul 2020 14:22:54 GMT
< Content-Type: text/html; charset=utf-8
< Content-Length: 213
< Connection: keep-alive
< Keep-Alive: timeout=20
< Cache-Control: private
< Location: /api/payer/auth?sessionToken=e744a95992fa405ba10662bbc6908d6bedd48a73cc0d45d589f4ef2f7d7a0b88
< Set-Cookie: returnUrl=http://example.com/returnurl.php; path=/
<
* Ignoring the response-body
* Connection #0 to host api.dev.walletone.com left intact
* Issue another request to this URL: 'https://api.dev.example.com/auth?sessionToken=e744b95992fa405ba10662bbc6908d6b7dd48a73cc0d45d589f4ef2f7d7a0b88'
* Switch from POST to GET
* Found bundle for host api.dev.example.com: 0x5649fd243480 [can pipeline]
* Re-using existing connection! (#0) with host api.dev.example.com
* Connected to api.dev.example.com (188.186.236.44) port 443 (#0)
> POST /auth?sessionToken=e744b95992fa405ba10662bbc6908d6b7dd48a73cc0d45d589f4ef2f7d7a0b88 HTTP/1.1
Host: api.dev.example.com
Content-Type: application/x-www-form-urlencoded
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8
< HTTP/1.1 411 Length Required
< Server: nginx
< Date: Mon, 13 Jul 2020 14:22:54 GMT
< Content-Type: text/html; charset=us-ascii
< Content-Length: 344
< Connection: keep-alive
< Keep-Alive: timeout=20
<
* Connection #0 to host api.dev.example.com left intact
My code is:
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $path);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_HTTPHEADER, Array (
"Content-Type: application/x-www-form-urlencoded",
"Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8"
));
curl_setopt($ch, CURLOPT_CUSTOMREQUEST, $curl_method);
curl_setopt($ch, CURLOPT_POSTFIELDS, $order_data);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
curl_setopt($ch, CURLOPT_VERBOSE, true);
curl_setopt($ch, CURLOPT_STDERR, $verbose);
$response = curl_exec($ch);
curl_close($ch);

Answer 1

Set the content-length in the header, which would be set to the string length strlen() of $order_data
curl_setopt($ch, CURLOPT_HTTPHEADER, Array (
"Content-Type: application/x-www-form-urlencoded",
"Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8",
"Content-Length: ". strlen($order_data)
));
you can also debug this by checking out curl_setopt($ch, CURLINFO_HEADER_OUT, true); which makes curl_getinfo() include the request's headers in its output.

Answer 2

The problem was in using curl_setopt($ch, CURLOPT_CUSTOMREQUEST, $curl_method). Curl tryed to swithc to GET, like mostly browsers do, but cannot. Use curl_setopt($ch, CURLOPT_POST, 1); indeed.