url-validation

I've been trying to figure out what the best way to validate a URL is (specifically in Python) but haven't really been able to find an answer. It seems like there isn't one known way to validate a URL, and it depends on what URLs you think you may need to validate. As well, I found it difficult to find an easy to read standard for URL structure. I did find the RFCs 3986 and 3987, but they contain much more than just how it is structured. Am I missing something, or is there no one standard way to validate a URL? bgschiller This looks like it might be a duplicate of How do you validate a URL

I want to check in django if a URL exists and if it does I want to show something on screen, i.e.: if URL_THAT_POINTS_TO_SOME_PDF exists SHOW_SOMETHING Bartek Edit: Please note, this is no longer valid for any version of Django above 1.5 I assume you want to check if the file actually exists, not if there is just an object (which is just a simple if statement) First, I will recommend always looking through Django's source code because you will find some great code that you could use :) I assume you want to do this within a template. There is no built-in template tag to validate a URL but you

I'm currently using the following regular expression to validation URLs: ^(?#Protocol)(?:(?:ht|f)tp(?:s?)\:\/\/|~\/|\/)?(?#Username:Password)(?:\w+:\w+@)? (?#Subdomains)(?:(?:[-\w]+\.)+(?#TopLevel Domains)(?:com|org|net|gov|mil|biz|edu|info|mobi|name|aero|jobs|museum|travel|[a-z]{2}))(?#Port)(?::[\d]{1,5})?(?#Directories)(?:(?:(?:\/(?:[-\w~!$+|.,=]|%[a-f\d]{2})+)+|\/)+|\?|#)?(?#Query)(?:(?:\?(?:[-\w~!$+|.,*:]|%[a-f\d{2}])+=?(?:[-\w~!$+|.,*:=]|%[a-f\d]{2})*)(?:&(?:[-\w~!$+|.,*:]|%[a-f\d{2}])+=?(?:[-\w~!$+|.,*:=]|%[a-f\d]{2})*)*)*(?#Anchor)(?:#(?:[-\w~!$+|.,*:=]|%[a-f\d]{2})*)?$ I borrowed this

Is there a good way to avoid the "host is not resolved" error that crashes an app? Some sort of a way to try connecting to a host ( like a URL ) and see if it's even valid? Use URLUtil to validate the URL as below. URLUtil.isValidUrl(url) It will return True if URL is valid and false if URL is invalid . Pranav URLUtil.isValidUrl(url); If this doesn't work you can use: Patterns.WEB_URL.matcher(url).matches(); Wrap the operation in a try/catch. There are many ways that a URL can be well-formed but not retrievable. In addition, tests like seeing if the hostname exists doesn't guarantee anything