Express: RegEx in routing params

[buschtoens]

Some syntax sugar. Would be cool, if express would parse RegEx's as a part of routing paths.

Example:

"/page/:page([0-9])"
"/skin/:direction([a-z])?/:resolution([0-9])?/:username"

Eveything in the braces should be parsed as a RegEx. That way more complex, but sweetend, paths could be built. :)

I know, that you can pass in RegEx's as a path, but then you'll end up with req.params as an array.

Yeah or No? Maybe I'll make a PR.

[jonathanong]

I would love to do something like /(page|post)/:id

[buschtoens]

That would be some kind of enum. I had that in mind aswell. That would internally translate to: /:path0(page|post)/:id.

[antitoxic]

Hmm.

Isn't app.param used for this? Of course app.param callbacks will execute for each route but if you want it only for a specific route, just add another middleware before you main callback and if the parameter doesn't match your regex run next('route').

app.get("/page/:page", function(req, res, next) {
  if  (!/^[0-9]+$/.test(req.params.page) next('route');
  next();
}, function(req, res, next){
  //...code that only run when `page` parameter is a integer
});

[buschtoens]

Uhm, yeah. That's a pssible work around, but it doesn't really look good and isn't as simple to use, as the proposed format.
Currently I pass in RegEx's as paths, and use the req.params array. But passing in a string and then using a real object seems cooler. :D

[71104]

up! this would be very useful to me too.

also, I would find useful specifying arrays of strings or regular expressions. for example, I would like to write:

app.get([
    '/page/:id',
    '/post/:id'
], function (request, response) {
    // ...
});

alternatively to:

app.get(/^\/(page|post)\/:id$/, function (request, response) {
    // ...
});

[buschtoens]

@71104 Same as this one. :wink:

[71104]

yeah, but I would also like the alternative of the arrays, at least for a matter of readability. :)

[buschtoens]

@71104 Ah, alright then. I openend a seperate issue for this. I think, I'll do a PR anytime soon and will include this aswell.

[tj]

stuff like /page/:page([0-9]) already works, you just have to double-escape slashes since it's s string

[buschtoens]

I don't get it. How do I have to change the string to make this route only catch urls of the form /\/page\/([0-9]+)/, where as ([0-9]+) should be exposed as req.params.page?

app.VERB("/page/:page([0-9]+)", function(req, res) {
  console.log(req.params.page);
});

[tj]

just like you have right there

[buschtoens]

Nevermind. :D
express-params kinda does, what I want. I just have to keep names consistent.

[norman784]

There is a way to check param length with a regex in the route like:

app.VERB("/:id({24})", function(req, res) {
  console.log(req.params.id);
});

Because i get

return new RegExp('^' + path + '$', sensitive ? '' : 'i');
                                                       ^
SyntaxError: Invalid regular expression: /^\/(?:({24}))\/?$/: Nothing to repeat

using express 3.0.0

[seandunaway]

like this:

server.get('/:id([a-zA-Z0-9]{24})', function(req, res) {
  console.log(req.params.id);
  res.end();
});

[norman784]

thanks @rump ! it works