Check if URL Exists

[dcool86]

I'm writing a script that needs to check if the url from tumblr.com is valid. What ive tried already dosnt seem to work.

$url = "test.tumblr.com";
$file_headers = @get_headers($file);
if($file_headers[0] == 'HTTP/1.1 404 Not Found') {
 echo "URL Not Valid";
}
else {
 echo "URL Vaild";
}

The scripts I have found on google always show the page valid.
If I change the url to

$url = "notavaildurl.tumblr.com";

I need it to say URL Not Valid. I know there has to be a way as other sites check for vaild tumblrs thanks.

[g1smd]

By testing for "not 404", URLs returning 301, 403, 503, even 500, will return as valid.

Surely only those returning "200 OK" (and maybe 301) should be classed as valid.

[lucy24]

For testing purposes, I'd add 304. "Yeah, yeah, it was here ten seconds ago and it hasn't changed."

What about 302?

[dcool86]

I was reading some where tumblr returns something diffrent if it isn't a vaild URL then if it was.

[lucy24]

Well, you can easily test that using an extension such as Live Headers. I tried it and, right off the bat, got

GET / HTTP/1.1
Host: www.tumblr.com
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.6; rv:6.0) Gecko/20100101 Firefox/6.0
... {et cetera}

HTTP/1.1 302 Found
Date: Mon, 12 Sep 2011 03:59:24 GMT
Server: Apache
P3P: CP="ALL ADM DEV PSAi COM OUR OTRo STP IND ONL"
Location: https://www.tumblr.com/

The 302 seems to be a reference to the http-to-https redirect. Ahem.

https://www.tumblr.com/why/_reasons

GET /why/_reasons HTTP/1.1
Host: www.tumblr.com

This is a little bit interesting, because I certainly didn't click on any such link, and the https page didn't re-redirect me.

Picking a link at random I clicked About, leading to a further 302 as I was redirected from https:// back to http:// (Conclusion: yeah, think you'd better include 302 in your options!)

And then I typed in /garbage on the assumption that they have no such directory, since they're not a big-city Municipal Services site. As one would hope, that led to a 404.

Along the way, there was a colossal number of calls to subdomain assets.tumblr.com; this is apparently where they keep their images, style sheets and so on.

Wonder what the recurring 642 query string in display-related requests is? I keep my browser windows pretty narrow, but not that narrow!

Sorry. What was the question again?

[penders]

$url = "test.tumblr.com"; 
$file_headers = @get_headers($file);

What is $file?

The URL you pass to get_headers() should be a full URL... "http://..."

print_r($file_headers)

to see what you are actually getting.

[dcool86]

Penders i copyed and pasted that part off the web forgot to change it as I was using it should be $url.

I can't even get it to print anything out.

[penders]

print_r(get_headers('http://webmasterworld.tumblr.com/'));

Array 
( 
  [0] => HTTP/1.1 200 OK 
  [1] => P3P: CP="ALL ADM DEV PSAi COM OUR OTRo STP IND ONL" 
  [2] => X-Tumblr-User: webmasterworld 
  [3] => Link: ; rel=icon 
  [4] => Vary: Accept-Encoding 
  [5] => X-Tumblr-Usec: D=99364 
  [6] => Content-Type: text/html; charset=UTF-8 
  [7] => Content-Length: 13378 
  [8] => Date: Tue, 13 Sep 2011 23:33:29 GMT 
  [9] => Connection: close 
)

print_r(get_headers('http://notavaildurl.tumblr.com/'));

Array 
( 
  [0] => HTTP/1.1 404 Not Found 
  [1] => P3P: CP="ALL ADM DEV PSAi COM OUR OTRo STP IND ONL" 
  [2] => Cache-Control: max-age=300 
  [3] => Vary: Accept-Encoding 
  [4] => X-Tumblr-Usec: D=25702 
  [5] => Content-Type: text/html; charset=UTF-8 
  [6] => Content-Length: 1870 
  [7] => Date: Tue, 13 Sep 2011 23:38:22 GMT 
  [8] => Connection: close 
)

[dcool86]

I get it now my question is how can I get the info on array 0 the code 200 only.


Thanks

[penders]

If you just want to check for 200 only then something similar to your initial code would suffice, if you want to check for multiple codes (as suggested) then perhaps a regex with preg_match() ?

[dcool86]

I finally got it to echo out what I want it to.


Thanks.

[lucy24]

Your original code was fine, you just got sidetracked because you were only looking for 404. The simplest division is

OK Response [23]\d\d
Not-OK Response [45]\d\d

One of them goes in the IF-- with appropriate pipes or Regular Expressions or whatever you use-- and the other becomes the ELSE. Which one goes first (the IF loop) may depend mainly on your coding style. Either the one that gets more "hits"-- probably the OK Responses, unless you're doing some hanky-panky with random URLs-- or the one that leads to the more complicated code (only you know this part).