route-matcher

Lightweight utility for converting route patterns into regular expressions.

Requires support for ES2018 RegExp named capture groups.

import { compile } from '@intrnl/route-matcher';

let pattern = compile('/foo/:bar');
// -> /^\/foo\/(?<bar>[^\/]+?)\/?$/i

Supported operators

For the sake of simplicity, only the commonly used pathing operators are supported by route-matcher.

Named parameters

Named parameters are defined by prefixing a colon to the parameter name.

let pattern = compile('/books/:genre');
// -> /^\/books\/(?<genre>[^\/]+?)\/?$/i

let match = pattern.exec('/books/fiction');
// match -> ['/books/fiction', 'fiction']
// match.groups -> { genre: 'fiction' }

Parameter names must only use a-zA-Z_, and JavaScript does not allow for multiple named capture groups of the same name.

Optional parameters

Parameters can be suffixed with ? to make them optional.

let pattern = compile('/movies/:genre/:title?');
// -> /^\/movies\/(?<genre>[^\/]+?)(?:\/(?<title>[^\/]+?))?\/?$/i

pattern.exec('/movies/action')?.groups;
// -> { genre: 'action', title: undefined }

pattern.exec('/movies/action/big-hero-6')?.groups;
// -> { genre: 'action', title: 'big-hero-6' }

Custom parameter matcher

Parameters have a default matcher of [^/]+?, which you can change to only allow for matching specific patterns.

let pattern = compile('/icon-:size(\\d+).png');
// -> /^\/icon-(?<size>\d+)\.png\/?$/i

pattern.exec('/icon-128.png')?.groups;
// -> { size: '128' }

pattern.exec('/icon-abc.png')?.groups;
// -> undefined

Parameter names must only use a-zA-Z_, and JavaScript does not allow for multiple named capture groups of the same name.

Custom prefix and suffix

Optional parameters matches up to the last /, for example:

let pattern = compile('/image-:size(\\d+)?');
// -> /^(?:\/image-(?<size>[^\/]+?))?\/?$/i

pattern.test('/');          // -> true
pattern.test('/image');     // -> false
pattern.test('/image-');    // -> false
pattern.test('/image-128'); // -> true

Parameters can include a custom prefix and suffix to be matched:

let pattern = compile('/image{-:size(\\d+)}?');
// -> /^\/image(?:-(?<size>\d+))?\/?$/i

pattern.test('/');          // -> false
pattern.test('/image');     // -> true
pattern.test('/image-');    // -> false
pattern.test('/image-128'); // -> true

Unsupported path operators

Custom matching modifiers

Any other modifiers, like * or :splat* and :foo+ are not supported, you can still make do with custom matchers instead.

let pattern = compile('/assets/:path(.+)');

pattern.exec('/assets/')?.groups;
// -> undefined

pattern.exec('/assets/images')?.groups;
// -> { path: 'images' }

pattern exec('/assets/images/icon')?.groups;
// -> { path: 'images/icon' }

Unnamed parameters

Unnamed parameters are not supported.

License

path-matcher © intrnl
Licensed under MIT