So I run a webgame over at http://ninjawars.net
Displaying externally hosted images
I want to provide embeddable images that aren’t avatars (I’m aware of and already using the great service of gravatar, but these images won’t be tied to any email), this is because I’ve found hosting your own uploaded images to often be a pain, and other people are already doing it better, so to speak.
Preventing excesses for external file sizes
However, this somewhat takes the control over the image size away. Using a simple link, this would allow the user to upload some large file size, and though it would be displayed with a certain display size in the css, it could force some silly long load time.
One way: Constraining the url
So I expect to need to limit the url parameters somewhat once they’re input by a user, limiting the options to certain image hosting services.
My initial thought with this is to require fixed sections of the url, a form that displays:
[http://flickr.com/photos/%5D [ put in the rest of your photo url here ] [/sizes/sq/]
So it’d limit the image to being hosted on flickr, and to a certain url that presumably sets the size on flickr, possibly with some back-end PHP processing that would strip any duplicate instances of the first and last parts of the url so that people can just post in the full url and have it work.
Better alternatives?
So the question is, is this a silly way to do it? Are there better javascript or php solutions already out there? How should I externally host images while still exerting some semblance of control? Or is this amount of control paranoid and not really necessary?
Use HTTP “HEAD” request to get file size w/o downloading it.
response field “Content-Length”.
Checking it in php or in js(ajax)… I would prefer js, cause it remove load from server to clients.
Also, according to HTTP 1.1 no more connection should be used from one user-agent. And many users of your server could result in many simultaneous connections from your server to image hosting server.