使用cURL从URL保存图像并将其保存到服务器会导致图像空白

Question

$camera_ip = "10.10.10.10";

$image_url = "http://$camera_ip/cgi-bin/image.jpg?camera=right&size=1024x768&quality=60";

$ch = curl_init($image_url);
curl_setopt($ch, CURLOPT_HEADER, 0);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_BINARYTRANSFER, 1);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, 1);
$rawdata = curl_exec($ch);
curl_close($ch);

$fp = fopen('./logo.jpg', 'wb');
fwrite($fp, $rawdata);
fclose($fp);

A file is being saved at 7KB but the size is 0x0 ... I can't figure out why the file isn't being saved correctly. My guess is that the file isn't being loaded fully before being saved, but is there a way of ensuring that?

Answer 1

Try using "w" instead of "wb" $fp = fopen('./logo.jpg', 'w'); Or try: file_put_contents('./logo.jpg',$rawdata); (not sure it is binary safe, should be)

And

Check your curl result to see what came back.

$info = var_export(curl_getinfo($ch),true);
file_put_contents('log.txt',$info);

OR

header('content-type: text/plain');
var_export(curl_getinfo($ch));

UPDATE

The curl Request failed (returned false).
Now you need to find out WHY.

For now change your:

curl_setopt($ch, CURLOPT_HEADER, 0);

To:

curl_setopt($ch, CURLINFO_HEADER_OUT, true);

Add these options for trouble shooting:

curl_setopt($ch, CURLOPT_ENCODING,"");   
curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 10);
curl_setopt($ch, CURLOPT_TIMEOUT,10);
curl_setopt($ch, CURLOPT_FAILONERROR,true);
curl_setopt($ch, CURLOPT_VERBOSE, true);

$data = curl_exec($ch);
if (curl_errno($ch)){
    echo ' Retrieve Base Page Error: ' . curl_error($ch);
}
else {
  $info = rawurldecode(var_export(curl_getinfo($ch),true));
  $skip = intval(curl_getinfo($ch, CURLINFO_HEADER_SIZE)); 
  $responseHeader= substr($data,0,$skip);
  $data= substr($data,$skip);
  echo "HEADER: $responseHeader\n";
  echo "\n\nINFO: $info\n\nDATA: $data";
}  

You will likely get the "Retrieve Base Page Error:" but it will also tell WHY it failed. If you cannot echo, replace echo with $info .=