Problems getting gzipped XML files with curl PHP - php

Question

I'm trying to grab data from an xml.gz file with curl. I'm able to download the file, but can't get the usable XML with any of my attempts. When I try to print the XML, I'm getting a long list of garbled special characters such as:
‹ì½ûrâÈ–7ú?E~{Çž¨Ši°î—Ù5=ÁÍ6]`Ø€ë²ãDLÈ u
Is there a simple way to just uncompress and encode this xml? Possibly through SimpleXML? The files are large and do require authentication. Here's my current code:
$username='username';
$password='password';
$location='http://www.example.com/file.xml.gz';
$ch = curl_init ();
curl_setopt($ch,CURLOPT_URL,$location);
curl_setopt($ch,CURLOPT_RETURNTRANSFER,1);
curl_setopt($ch,CURLOPT_USERPWD,"$username:$password");
curl_setopt($ch, CURLOPT_TIMEOUT, 60);
curl_setopt($ch, CURLOPT_HEADER, 0);
$xmlcontent = curl_exec ($ch);
curl_close($ch);
print_r($xmlcontent);
Thanks for your help!

Answer 1

You will need to pass the string through gzuncompress: http://www.php.net/manual/en/function.gzuncompress.php

Answer 2

You first need to save the file to disk. As it's gz-compressed you need to uncompress it before you can access the (uncompressed) XML. This can be done with the zlib:// -- bzip2:// -- zip:// — Compression Streams in PHP:
$file = 'compress.zlib://file.xml.gz';
################
$xml = simplexml_load_file($file);
To get this to work, you need to have the ZLib extension installed/configured.
Wrapper means that you're not creating an uncompressed variant of that file first (create a second file, which can be a solution ,too) but the wrapper uncompresses the data of that file transparently on the fly so that the simplexml library can operate on the uncompressed XML (and that is what that library needs: uncompressed XML).
See as well:
Sorting and grouping SimpleXML Data (example of using xml.gz file with SimpleXMLElement)
Parsing extremely large XML files in php (example of using xml.gz file with XMLReader)

Answer 3

Not sure why, but none of the other answers worked for me in the end. zlib was installed on the server, but the gzdecode() function was not defined in the library, and the gzuncompress gave me errors, as did compress.zlib://. They might work for you so, give them a try as well.
If you need to check if zlib is installed this stackoverflow answer or this answer can help. They provide this script:
<?php
echo phpversion().", ";
if (function_exists("gzdecode")) {
echo "gzdecode OK, ";
} else {
echo "gzdecode no OK, ";
}
if (extension_loaded('zlib')) {
echo "zlib extension loaded ";
} else {
echo "zlib extension not loaded ";
}
?>
This site gives another script that shows what zlib function are installed:
var_dump(get_extension_funcs('zlib'));
SOLUTION!!! These 2 functions did the trick for me. Just curl or use file_get_contents to grab the xml file, then use this script:
$xmlcontent = gzinflate(substr($xmlcontent,10,-8));
OR use this script to grab the xml file and get the contents (see more here):
$zd = gzopen($filename,"r");
$contents = gzread($zd,$fileSize);
gzclose($zd);
Thanks to all who helped me get this answer. Hope this helps someone else!

Answer 4

I suggest you just decompress the result you fetch:
//[...]
$xmlcontent = gzdecode ( curl_exec($ch) );
curl_close($ch);
print_r($xmlcontent);
Obviously you should do some additional error checking, this is just the shortened general approach.
Note that there are two similar functions provided by php:
gzuncompress()
gzdecode()
Most likely you have to use the second one, if the file really is a physical gzip compressed file delivered by a http server.