Edit file File name : PrepareBodyMiddleware.php Content :<?php namespace WPMailSMTP\Vendor\GuzzleHttp; use WPMailSMTP\Vendor\GuzzleHttp\Promise\PromiseInterface; use WPMailSMTP\Vendor\Psr\Http\Message\RequestInterface; /** * Prepares requests that contain a body, adding the Content-Length, * Content-Type, and Expect headers. * * @final */ class PrepareBodyMiddleware { /** * @var callable(RequestInterface, array): PromiseInterface */ private $nextHandler; /** * @param callable(RequestInterface, array): PromiseInterface $nextHandler Next handler to invoke. */ public function __construct(callable $nextHandler) { $this->nextHandler = $nextHandler; } public function __invoke(\WPMailSMTP\Vendor\Psr\Http\Message\RequestInterface $request, array $options) : \WPMailSMTP\Vendor\GuzzleHttp\Promise\PromiseInterface { $fn = $this->nextHandler; // Don't do anything if the request has no body. if ($request->getBody()->getSize() === 0) { return $fn($request, $options); } $modify = []; // Add a default content-type if possible. if (!$request->hasHeader('Content-Type')) { if ($uri = $request->getBody()->getMetadata('uri')) { if (\is_string($uri) && ($type = \WPMailSMTP\Vendor\GuzzleHttp\Psr7\MimeType::fromFilename($uri))) { $modify['set_headers']['Content-Type'] = $type; } } } // Add a default content-length or transfer-encoding header. if (!$request->hasHeader('Content-Length') && !$request->hasHeader('Transfer-Encoding')) { $size = $request->getBody()->getSize(); if ($size !== null) { $modify['set_headers']['Content-Length'] = $size; } else { $modify['set_headers']['Transfer-Encoding'] = 'chunked'; } } // Add the expect header if needed. $this->addExpectHeader($request, $options, $modify); return $fn(\WPMailSMTP\Vendor\GuzzleHttp\Psr7\Utils::modifyRequest($request, $modify), $options); } /** * Add expect header */ private function addExpectHeader(\WPMailSMTP\Vendor\Psr\Http\Message\RequestInterface $request, array $options, array &$modify) : void { // Determine if the Expect header should be used if ($request->hasHeader('Expect')) { return; } $expect = $options['expect'] ?? null; // Return if disabled or if you're not using HTTP/1.1 or HTTP/2.0 if ($expect === \false || $request->getProtocolVersion() < 1.1) { return; } // The expect header is unconditionally enabled if ($expect === \true) { $modify['set_headers']['Expect'] = '100-Continue'; return; } // By default, send the expect header when the payload is > 1mb if ($expect === null) { $expect = 1048576; } // Always add if the body cannot be rewound, the size cannot be // determined, or the size is greater than the cutoff threshold $body = $request->getBody(); $size = $body->getSize(); if ($size === null || $size >= (int) $expect || !$body->isSeekable()) { $modify['set_headers']['Expect'] = '100-Continue'; } } } Save