Flagrant Badassery

A JavaScript and regular expression centric blog

parseUri 1.2: Split URLs in JavaScript

Thursday, June 28th, 2007 • Related • Filed Under

I've just updated parseUri. If you haven't seen the older version, parseUri is a function which splits any well-formed URI into its parts, all of which are optional. Its combination of accuracy, flexibility, and brevity is unrivaled.

Highlights:

  • Comprehensively splits URIs, including splitting the query string into key/value pairs. (Enhanced)
  • Two parsing modes: loose and strict. (New)
  • Easy to use (returns an object, so you can do, e.g., parseUri(uri).anchor).
  • Offers convenient, pre-concatenated components (path = directory and file; authority = userInfo, host, and port; etc.)
  • Change the default names of URI parts without editing the function, by updating parseUri.options.key. (New)
  • Exceptionally lightweight (1 KB before minification or gzipping).
  • Released under the MIT License.

Try the demo, but make sure to come back and read the details below.

Details:

Older versions of this function used what's now called loose parsing mode (which is still the default in this version). Loose mode deviates slightly from the official generic URI spec (RFC 3986), but by doing so allows the function to split URIs in a way that most end users would expect intuitively. However, the finer details of loose mode preclude it from properly handling relative paths which do not start from root (e.g., "../file.html" or "dir/file.html"). On the other hand, strict mode attempts to split URIs according to RFC 3986. Specifically, in loose mode, directories don't need to end with a slash (e.g., the "dir" in "/dir?query" is treated as a directory rather than a file name), and the URI can start with an authority without being preceded by "//" (which means that the "yahoo.com" in "yahoo.com/search/" is treated as the host, rather than part of the directory path).

Since I've assumed that most developers will consistently want to use one mode or the other, the parsing mode is not specified as an argument when running parseUri, but rather as a property of the parseUri function itself. Simply run the following line of code to switch to strict mode:

parseUri.options.strictMode = true;

From that point forward, parseUri will work in strict mode (until you turn it back off).

The code:

// parseUri 1.2.2
// (c) Steven Levithan <stevenlevithan.com>
// MIT License

function parseUri (str) {
	var	o   = parseUri.options,
		m   = o.parser[o.strictMode ? "strict" : "loose"].exec(str),
		uri = {},
		i   = 14;

	while (i--) uri[o.key[i]] = m[i] || "";

	uri[o.q.name] = {};
	uri[o.key[12]].replace(o.q.parser, function ($0, $1, $2) {
		if ($1) uri[o.q.name][$1] = $2;
	});

	return uri;
};

parseUri.options = {
	strictMode: false,
	key: ["source","protocol","authority","userInfo","user","password","host","port","relative","path","directory","file","query","anchor"],
	q:   {
		name:   "queryKey",
		parser: /(?:^|&)([^&=]*)=?([^&]*)/g
	},
	parser: {
		strict: /^(?:([^:\/?#]+):)?(?:\/\/((?:(([^:@]*)(?::([^:@]*))?)?@)?([^:\/?#]*)(?::(\d*))?))?((((?:[^?#\/]*\/)*)([^?#]*))(?:\?([^#]*))?(?:#(.*))?)/,
		loose:  /^(?:(?![^:@]+:[^:@\/]*@)([^:\/?#.]+):)?(?:\/\/)?((?:(([^:@]*)(?::([^:@]*))?)?@)?([^:\/?#]*)(?::(\d*))?)(((\/(?:[^?#](?![^?#\/]*\.[^?#\/.]+(?:[?#]|$)))*\/?)?([^?#\/]*))(?:\?([^#]*))?(?:#(.*))?)/
	}
};

You can download it or run the test suite.

parseUri has no dependencies, and has been tested in IE 5.5–7, Firefox 2.0.0.4, Opera 9.21, Safari 3.0.1 beta for Windows, and Swift 0.2.

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There Are 209 Responses So Far. »

  1. Comment by Lindsey on 22 January 2016:

    Quality articles is the important to attract the visitors to go
    to see the web site, that’s what this website is providing.

  2. Comment by Vibhav Agrawal on 1 September 2016:

    Hello Steven,
    We were using this script and it really works well.
    However, recently, we ran into an issue, if we use IPv6 URL [like http://%5B2001:ae::52]/index.html?query=value ]
    The script ends up with incorrect parameter values for file, host, path etc.

    So, I was wondering if there is a newer version which handles IPv6 URIs as well?

    Thanks in advance.

    Thanks,
    Vibhav

  3. Pingback by URL Parser on 29 October 2016:

    […] Flagrant Badassery – parseUri 1.2: Split URLs in JavaScript […]

  4. Comment by Mezoderma Review on 21 March 2017:

    Amazing! Its actually amazing article, I have got much clear idea on the topic of from
    this post.

  5. Pingback by Extract hostname name from string - QuestionFocus on 21 December 2017:

    […] because you can have port numbers and special chars. As such, I recommend using something like parseUri to do this for you. I doubt performance is going to be a issue unless you are parsing hundreds of […]

  6. Pingback by Reusable Javascript Functions – Sam East on 22 December 2017:

    […] Url parser taken from this resource. http://blog.stevenlevithan.com/archives/parseuri […]

  7. Comment by Orange Beach Activities on 28 August 2018:

    Thanks to my father who stated to me regarding this blog, this blog is genuinely awesome.

  8. Comment by Rudiger on 1 October 2018:

    I wish it had the same property names as are available on window.location or in the URL class:
    hash, search, href, origin, pathname

  9. Comment by nathan king on 30 October 2018:

    thank you.

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