PHP禁用cURL时，如何获取400状态请求的响应体？

Ah, I’ve dealt with this exact frustration before! The default behavior of file_get_contents() is to throw out the response body whenever it encounters an HTTP error status code (like 400 Bad Request), which is why you can only grab the headers via $http_response_header but not the actual body. Luckily, there’s a straightforward workaround using PHP’s stream contexts.

The Solution: Enable ignore_errors in the Stream Context #

You just need to create a custom stream context that tells PHP to ignore HTTP error statuses and return the response body regardless. Here’s a complete example:

// Create a stream context with error handling disabled
$context = stream_context_create([
    'http' => [
        'ignore_errors' => true, // This is the critical setting
        // Add any additional headers your request needs
        'header' => [
            'Content-Type: application/json',
            'Accept: application/json'
        ]
    ]
]);

// Your target API endpoint
$apiUrl = 'https://your-target-api.com/endpoint';

// Fetch the response (including body for 400 statuses now!)
$responseBody = file_get_contents($apiUrl, false, $context);

// Verify the response body
var_dump($responseBody);

// Optional: Extract the status code from $http_response_header
$statusCode = null;
foreach ($http_response_header as $headerLine) {
    // Check for the HTTP status line (works for HTTP/1.x and HTTP/2)
    if (preg_match('/^HTTP\/\d+\.\d+\s+(\d+)/', $headerLine, $matches)) {
        $statusCode = (int)$matches[1];
        break;
    }
}

echo "HTTP Status Code: " . $statusCode;

Key Notes: #

• ignore_errors: This flag overrides PHP’s default behavior of treating non-2xx statuses as failures, ensuring the response body is returned even for 400, 404, 500, etc.
• Handling POST Requests: If you need to send a POST request, add the method and content parameters to the stream context:

  $context = stream_context_create([
      'http' => [
          'ignore_errors' => true,
          'method' => 'POST',
          'header' => 'Content-Type: application/x-www-form-urlencoded',
          'content' => http_build_query(['key' => 'value', 'another_key' => 'another_value'])
      ]
  ]);
  

• Legacy PHP Versions: If you’re using PHP < 8.0, avoid str_starts_with() and use the regex check or substr($headerLine, 0, 5) === 'HTTP/' to detect the status line.

This approach keeps you within the constraints of not using cURL and lets you access the full response data for any HTTP status code.

内容的提问来源于stack exchange，提问作者Samul