Regex to match url path - Golang with Gorilla Mux

1
votes

I'm setting up an api endpoint which after parsing the url I would get a path such as /profile/<username> e.g. /profile/markzuck

The username is optional though as this endpoint returns the the authenticated users profile if username is blank

Rule set:
I'm not the best at regex but I've created an expression that requires /profile after that if there is a following / e.g. /profile/ then you need to have a <username> that matches (\w){1,15}. Also I want it to be allowed to match any number of combinations if there is another following / e.g. /profile/<username>/<if preceding "/" then anything else>

Although I'm not 100% sure my expression is correct this seems to work in JavaScript
/^\/(profile)(\/(?=(\w){1,15}))?/

Gorilla Mux though is different and it requires the route matching string to always start with a slash and some other things I don't understand like it can only use non-capturing groups
( found this out by getting this error: panic: route /{_dummy:profile/([a-zA-Z_])?} contains capture groups in its regexp. Only non-capturing groups are accepted: e.g. (?:pattern) instead of (pattern) )

I tried using the same expression I used for JavaScript which didn't work here. I created a more forgiving expresion handlerFunc("/{_dummy:profile\/[a-zA-Z_].*}") which does work however this doesn't really follow the same rule set I'm using in my JavaScript expresion.

I was able to come up with my working expresion from this SO post here
And Gorilla Mux's docs talks a little bit about how their regex works when explaining how to use the package in the intro section here

My question is what is a similar or equivalent expression to the rule set I described that will work in Gorilla Mux HandlerFunc()?

1
regexgogorilla

1 Answers

2
votes

If you're doing this with mux, then I believe what you need is not regex, but multiple paths.

For the first case, use a path "/profile". For the one containing a user name, use another path "/profile/{userName}". If you really want to use a regex, you can do "/profile/{username:}" to validate the user name. If you need to process anything that comes after username, either register separate paths (/profile/{username}/otherstuff), or register a pathPrefix "/profile/{username}/" and process the remaining part of the URL manually.