为什么我的HTTP请求从PHP失败？

Question

I try to submit a form to remote server: http://openconvert.clarin.inl.nl/openconvert/tagger#text, as you can see the required fileds are input and format, and the action url is http://openconvert.clarin.inl.nl/openconvert/text/, so I try the following in php:

<?php
function do_post_request($url, $data, $optional_headers = null)
{
  $params = array('http' => array(
    'method' => 'POST',
    'content' => $data
  ));
  if ($optional_headers !== null) {
    $params['http']['header'] = $optional_headers;
  }
  $ctx = stream_context_create($params);
  $fp = @fopen($url, 'rb', false, $ctx);
  if (!$fp) {
    throw new Exception("Problem with $url, $php_errormsg");
  }
  $response = @stream_get_contents($fp);
  if ($response === false) {
    throw new Exception("Problem reading data from $url, $php_errormsg");
  }
  return $response;
}
$remoteurl="http://openconvert.clarin.inl.nl/openconvert/text";
$rawdata=array(
  'input'=>'test',
  'format'=>'text');
$data=http_build_query($rawdata, '', '&amp;'); //flags_, myvar_
var_dump($data);
echo "<br />";
echo do_post_request($remoteurl,$data,'Content-Type: text/html');
?>

I don't know why the server can't find my data?

The output is:

string(26) "input=test&format=text"
<br /><?xml version="1.0" encoding="UTF-8"?>
<error>Insufficient parameters. Required parameters: input, format</error>

Answer 1

There might be other problems, but the & value in http_build_query is definitely wrong. You're not embedding your urlencoded data into an html document, so you should not html-escape the ampersand. Replacing that line with:

http_build_query($rawdata, '', '&'); 

should be better, but it might not be 100% of your solution.

P.S.: Don't use @, ever. You are suppressing real errors that you should see.