freebase cURL and mqlwrite with PHP

Hi am doing some testing on the Freebase sandbox, but I can't get the following request to work. It hangs for ages then returns nothing. I have also outputted curl_getinfo() if it helps anyone work out where I am going wrong.

echo $uri = "http://".$this->config['apiSandboxHost'].'/'.$this->config['apiWritePath'].'={"create":"unless_exists","type":"/user/docs/music/note","name":"A","id":null}';

$ch = curl_init($uri);
curl_setopt($ch, CURLOPT_HEADER, 1);
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
$headers = array();
$headers[] = 'X-Metaweb-Request : idio';
$headers[] = 'Content-length: 78';
$headers[] = 'Content-type: application/x-www-form-urlencoded';
$headers[] = 'Cookie: '.  implode(';', $this->authCookies);
curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
$output = curl_exec($ch);
pr(curl_getinfo($ch));
curl_close(开发者_如何学Go$ch);
echo $output;

Output

http://sandbox.freebase.com/api/service/mqlwrite?query={"create":"unless_exists","type":"/user/docs/music/note","name":"A","id":null}

Array
(
    [url] => http://sandbox.freebase.com/api/service/mqlwrite?query={"create":"unless_exists","type":"/user/docs/music/note","name":"A","id":null}
    [content_type] => 
    [http_code] => 0
    [header_size] => 0
    [request_size] => 693
    [filetime] => -1
    [ssl_verify_result] => 0
    [redirect_count] => 0
    [total_time] => 285.371
    [namelookup_time] => 0
    [connect_time] => 0.185
    [pretransfer_time] => 0.185
    [size_upload] => 0
    [size_download] => 0
    [speed_download] => 0
    [speed_upload] => 0
    [download_content_length] => 0
    [upload_content_length] => -1
    [starttransfer_time] => 285.371
    [redirect_time] => 0
)

Thanks in advance for any help!

It ended up being an issue with the way I was sending data to freebase. Once I added

curl_setopt($ch, CURLOPT_POSTFIELDS, $query);

it all worked fine.

It was weird as I could only get it working when I sent the data as a post variable and also added content to the query string of the request.