slevithan / parseuri

Mighty but tiny URI parser

parseUri

parseUri is a mighty but tiny JavaScript URI/URN/URL parser that splits any URI into its parts (all of which are optional). Its combination of accuracy, comprehensiveness, and brevity is unrivaled (1KB min/gzip, with no dependencies).

Breaking changes

Version 2 was a major, breaking change that might require updating URI part names in your code and/or providing 'friendly' as a second argument to preserve the previous default handling of relative paths. See details in the v2 release notes, and compare results with v1.2.2 on the demo page. Version 3 was a minor update published on npm as pure ESM.

Compared to the URL constructor

parseUri includes several advantages over the built-in URL:

• It gives you many additional properties (authority, userinfo, subdomain, domain, tld, resource, directory, filename, suffix) that aren’t available from URL.
• URL throws e.g. if not given a protocol, and in many other cases of valid (but not supported) and invalid URIs. parseUri makes a best case effort even with partial or invalid URIs and is extremely good with edge cases.
• URL’s rules don’t allow correctly handling many non-web protocols. For example, URL doesn’t throw on any of 'git://localhost:1234', 'ssh://[email protected]', or 't2ab:///path/entry', but it also doesn’t get their details correct since it treats everything after <non-web-protocol>: up to ? or # as part of the pathname.
• parseUri includes a “friendly” parsing mode (in addition to its default mode) that handles human-friendly URLs like 'example.com/file.html' as expected.
• parseUri supports providing a list of second-level domains that should be treated as part of the top-level domain (ex: co.uk).

Conversely, parseUri is single-purpose and doesn’t apply normalization.

You can compare with URL’s results on the demo page.

Results / URI parts

Returns an object with 20 URI parts as properties plus queryParams, a URLSearchParams object that includes methods get(key), getAll(key), etc.

Here’s an example of what each part contains:

┌──────────────────────────────────────────────────────────────────────────────────────────────────────────┐
│                                                  href                                                    │
├────────────────────────────────────────────────────────────────┬─────────────────────────────────────────┤
│                             origin                             │                resource                 │
├──────────┬─┬───────────────────────────────────────────────────┼──────────────────────┬───────┬──────────┤
│ protocol │ │                     authority                     │       pathname       │ query │ fragment │
│          │ ├─────────────────────┬─────────────────────────────┼───────────┬──────────┤       │          │
│          │ │      userinfo       │            host             │ directory │ filename │       │          │
│          │ ├──────────┬──────────┼──────────────────────┬──────┤           ├─┬────────┤       │          │
│          │ │ username │ password │       hostname       │ port │           │ │ suffix │       │          │
│          │ │          │          ├───────────┬──────────┤      │           │ ├────────┤       │          │
│          │ │          │          │ subdomain │  domain  │      │           │ │        │       │          │
│          │ │          │          │           ├────┬─────┤      │           │ │        │       │          │
│          │ │          │          │           │    │ tld │      │           │ │        │       │          │
"  https   ://   user   :   pass   @ sub1.sub2 . dom.com  : 8080   /p/a/t/h/  a.html    ?  q=1  #   hash   "
└──────────────────────────────────────────────────────────────────────────────────────────────────────────┘

If this chart isn’t appearing correctly, view it on GitHub.

parseUri additionally supports IPv4 and IPv6 addresses, URNs, and many edge cases not shown here. See the extensive tests. References include RFC 3986 and WHATWG URL.

Parsing modes

parseUri has two parsing modes (default and friendly), specified via an optional second argument:

// Default mode
parseUri(uri);
// Also default mode
parseUri(uri, 'default');
// Friendly mode
parseUri(uri, 'friendly');

The default mode follows official URI standards, whereas friendly mode handles human-friendly URLs like 'example.com/file.html' as expected. Results are identical for any URI that starts with <protocol>://, <web-protocol>:, :, //, /, \, ?, or #.

To be precise, the only difference is that friendly mode doesn’t require <protocol>:, :, //, or other repeating slashes to signal the start of an authority. This has the following effects:

• It allows starting a URI with an authority (as noted).
• It therefore precludes proper handling for relative paths (without a leading / or \) such as 'dir/file.html'. Friendly mode considers it to start with hostname dir.
• It avoids requiring // after a non-web protocol.
  • Note: The web protocols http, https, ws, wss, and ftp never require //; friendly mode extends this to non-web protocols.

You can compare results from default and friendly mode on the demo page.

Examples

let uri = parseUri('https://a.b.example.com:80/@user/a/my.img.jpg?q=x&q=#hash');
uri.protocol // → 'https'
uri.host // → 'a.b.example.com:80'
uri.hostname // → 'a.b.example.com'
uri.subdomain // → 'a.b'
uri.domain // → 'example.com'
uri.port // → '80'
uri.resource // → '/@user/a/my.img.jpg?q=x&q=#hash'
uri.pathname // → '/@user/a/my.img.jpg'
uri.directory // → '/@user/a/'
uri.filename // → 'my.img.jpg'
uri.suffix // → 'jpg'
uri.query // → 'q=x&q='
uri.fragment // → 'hash'
uri.queryParams.get('q') // → 'x'
uri.queryParams.getAll('q') // → ['x', '']
uri.queryParams.get('not-present') // → null
uri.queryParams.getAll('not-present') // → []
// Also available: href, origin, authority, userinfo, username, password, tld

// Relative path
uri = parseUri('dir/file.html?q=x');
uri.hostname // → ''
uri.directory // → 'dir/'
uri.filename // → 'file.html'
uri.query // → 'q=x'

// Friendly mode allows starting with an authority
uri = parseUri('example.com/file.html', 'friendly');
uri.hostname // → 'example.com'
uri.directory // → '/'
uri.filename // → 'file.html'

// IPv4 address
uri = parseUri('ssh://[email protected]');
uri.protocol // → 'ssh'
uri.username // → 'myid'
uri.hostname // → '192.168.1.101'
uri.domain // → ''

// IPv6 address
uri = parseUri('https://[2001:db8:85a3::7334]:80?q=x');
uri.hostname // → '[2001:db8:85a3::7334]'
uri.port // → '80'
uri.domain // → ''
uri.query // → 'q=x'

// Mailto
uri = parseUri('mailto:[email protected]?subject=Hey&body=Sign%20me%20up!');
uri.protocol // → 'mailto'
uri.authority // → ''
uri.username // → ''
uri.hostname // → ''
uri.pathname // → '[email protected]'
uri.query // → 'subject=Hey&body=Sign%20me%20up!'
uri.queryParams.get('body') // → 'Sign me up!'

// Mailto in friendly mode
uri = parseUri('mailto:[email protected]', 'friendly');
uri.protocol // → 'mailto'
uri.authority // → '[email protected]'
uri.username // → 'me'
uri.hostname // → 'my.com'
uri.pathname // → ''

/* Also supports e.g.:
- https://[2001:db8:85a3::7334%en1]/ipv6-with-zone-identifier
- git://localhost:1234
- file:///path/file
- tel:[phone]
- urn:uuid:c5542ab6-3d96-403e-8e6b-b8bb52f48d9a?q=x
*/

Test and compare results on the demo page.

Install

npm install parseuri

Use

import { parseUri, setTlds } from 'parseuri';

In browsers:

<script src="https://cdn.jsdelivr.net/npm/parseuri/dist/parseuri.min.js"></script>
<script>
  console.log(parseUri('https://example.com/'));
  // If needed, use `parseUri.setTlds`
</script>