保存来自 Google Places 的照片副本 API Place Photos using curl

Question

I'm trying to grab a photo from Google Place Photos using curl and save it on my server.

The request format as per the Google API documentation is like this:

https://maps.googleapis.com/maps/api/place/photo?maxwidth=400&photoreference=CoQBegAAAFg5U0y-iQEtUVMfqw4KpXYe60QwJC-wl59NZlcaxSQZNgAhGrjmUKD2NkXatfQF1QRap-PQCx3kMfsKQCcxtkZqQ&sensor=true&key=AddYourOwnKeyHere

So I tried this function:

function download_image1($image_url, $image_file){
    $fp = fopen ($image_file, 'w+');
    $ch = curl_init($image_url);
    // curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false); // enable if you want
    curl_setopt($ch, CURLOPT_FILE, $fp); // output to file
    curl_setopt($ch, CURLOPT_FOLLOWLOCATION, 1);
    curl_setopt($ch, CURLOPT_TIMEOUT, 1000); // some large value to allow curl to run for a long time
    curl_setopt($ch, CURLOPT_USERAGENT, 'Mozilla/5.0');
    // curl_setopt($ch, CURLOPT_VERBOSE, true); // Enable this line to see debug prints
    curl_exec($ch);
    curl_close($ch); // closing curl handle
    fclose($fp); // closing file handle
}

download_image1($photo, "test.jpg");

..where $photo holds the request url.

This is not working, it saves an empty image with header errors, it probably is because the request is not the actual url of the photo. Also, in the request url, it's not possible to know which image extension I'm going to get (jpg, png, gif, etc) so that's another problem.

Any help on how to save the photos appreciated.

EDIT: I get the header errors "Can't read file header" in my image viewer software when I try to open the image. The script itself doesn't show any errors.

Answer 1

I found a solution here: http://kyleyu.com/?q=node/356

It gives a very useful function to return the actual URL after redirection:

function get_furl($url)
    {
    $furl = false;
    // First check response headers
    $headers = get_headers($url);
    // Test for 301 or 302
    if(preg_match('/^HTTP\/\d\.\d\s+(301|302)/',$headers[0]))
        {
        foreach($headers as $value)
            {
            if(substr(strtolower($value), 0, 9) == "location:")
                {
                $furl = trim(substr($value, 9, strlen($value)));
                }
            }
        }
    // Set final URL
    $furl = ($furl) ? $furl : $url;
    return $furl;
    }

So you pass the Google Place Photo request uRL to this function and it returns the actual URL of the photo after the redirection which then can be used with CURL. It also explains that sometimes, the curl option curl_setopt($ch, CURLOPT_FOLLOWLOCATION, 1); doesn't always work.

Answer 2

https://stackoverflow.com/a/23540352/2979237

We can minimize the above code to change as adding 1 as the second parameter of get_header() function like $headers = get_headers($url, 1); . that will return the associate values.