Re: Using fopen or SQL to check image

On 25 June 2010 21:02, Ashley Sheridan <ash@ashleysheridan.co.uk> wrote: > > On Fri, 2010-06-25 at 21:01 +0200, Peter Lind wrote: > > On 25 June 2010 20:59, Ashley Sheridan <ash@ashleysheridan.co.uk> wrote: > > > > On Fri, 2010-06-25 at 20:57 +0200, Peter Lind wrote: > > > > On 25 June 2010 19:35, Ashley Sheridan <ash@ashleysheridan.co.uk> wrote: > > > On Fri, 2010-06-25 at 19:31 +0200, Karl Cifius wrote: > > > > > >> Hi, > > >> > > >> I'm making a Facebook application that can generate images to user's > > >> albums. To publish a story a thumbnail of this image is stored on my > > >> server. Since this server currently is very limited I want to be able > > >> to clean these thumbnails pretty often. > > >> > > >> To not get broken links in older facebook stories the address to the > > >> thumbnail is a php script that checks if the thumbnail is available > > >> and returns it, or otherwise returns a default thumbnail. > > >> > > >> I have solved this using the following code: > > >> > > >> $tImage = $_GET['i']; > > >> $tURL   = "upload/$tImage.jpg"; > > >> if(!($fp=fopen($tURL,"rb"))){ > > >>    header("Location: thumb.jpg"); > > >> }else{ > > >>    header("Location: upload/$tImage.jpg"); > > >>    fclose($fp); > > >> } > > >> > > >> My question is if it would be better to have a mysql database with > > >> information about the thumbnail and check if the image is there, > > >> instead of checking if the image file can be loaded? What is the most > > >> optimized approach if I start to gain traffic? > > >> > > >> > > >> Thanks, > > >> > > >> /Karl > > >> > > > > > > > > > I think checking for the existence of a file is probably going to be the > > > quicker approach. Unless you have a server with loads of RAM and your DB > > > is very small, it's unlikely your DB will exist entirely in memory, so > > > you will at some point have to access the files that the DB uses, even > > > though this is done by the server automatically. > > > > > > On another note, I would try to sanitise that $_GET variable a bit, as > > > it could lead to issues down the line later. Maybe limit the string to > > > patterns you expect for an image URL. > > > > > > Thanks, > > > Ash > > > http://www.ashleysheridan.co.uk > > > > > > > Might be quicker to do with a .htaccess file - you can avoid loading php at all. > > > > Regards > > Peter > > > > > > > > PHP can do things that .htaccess can't, like verify a specific ID has access to an > > image, etc. > > > > I must've missed the part in the code where the ID was checked ... > Nope, still can't find it. > > Regards > Peter > > > -- > <hype> > WWW: http://plphp.dk / http://plind.dk > > LinkedIn: http://www.linkedin.com/in/plind > BeWelcome/Couchsurfing: Fake51 > Twitter: http://twitter.com/kafe15 > </hype> > > It wasn't in the example, but generally I've found the only reason someone ever > thinks of doing something like this rather than directly link to the image is for some sort of > validation reason. I assumed it was a slimmed-down code sample that only showed us what we needed. > Ahh, I see. I assumed the OP would have told us if that was the case - I prefer answering the stated questions instead of guessing at what they are. Regards Peter -- <hype> WWW: http://plphp.dk / http://plind.dk LinkedIn: http://www.linkedin.com/in/plind BeWelcome/Couchsurfing: Fake51 Twitter: http://twitter.com/kafe15 </hype>