How do I parse a URL into hostname and path in javascript?

Question

I would like to take a string

var a = \"http://example.com/aa/bb/\"

and process it into an object such that

a.hostname == \         


        

Answer 1

Simple and robust solution using the module pattern. This includes a fix for IE where the pathname does not always have a leading forward-slash (/).

I have created a Gist along with a JSFiddle which offers a more dynamic parser. I recommend you check it out and provide feedback.

var URLParser = (function (document) {
    var PROPS = 'protocol hostname host pathname port search hash href'.split(' ');
    var self = function (url) {
        this.aEl = document.createElement('a');
        this.parse(url);
    };
    self.prototype.parse = function (url) {
        this.aEl.href = url;
        if (this.aEl.host == "") {
           this.aEl.href = this.aEl.href;
        }
        PROPS.forEach(function (prop) {
            switch (prop) {
                case 'hash':
                    this[prop] = this.aEl[prop].substr(1);
                    break;
                default:
                    this[prop] = this.aEl[prop];
            }
        }, this);
        if (this.pathname.indexOf('/') !== 0) {
            this.pathname = '/' + this.pathname;
        }
        this.requestUri = this.pathname + this.search;
    };
    self.prototype.toObj = function () {
        var obj = {};
        PROPS.forEach(function (prop) {
            obj[prop] = this[prop];
        }, this);
        obj.requestUri = this.requestUri;
        return obj;
    };
    self.prototype.toString = function () {
        return this.href;
    };
    return self;
})(document);

Demo

var URLParser = (function(document) {
  var PROPS = 'protocol hostname host pathname port search hash href'.split(' ');
  var self = function(url) {
    this.aEl = document.createElement('a');
    this.parse(url);
  };
  self.prototype.parse = function(url) {
    this.aEl.href = url;
    if (this.aEl.host == "") {
      this.aEl.href = this.aEl.href;
    }
    PROPS.forEach(function(prop) {
      switch (prop) {
        case 'hash':
          this[prop] = this.aEl[prop].substr(1);
          break;
        default:
          this[prop] = this.aEl[prop];
      }
    }, this);
    if (this.pathname.indexOf('/') !== 0) {
      this.pathname = '/' + this.pathname;
    }
    this.requestUri = this.pathname + this.search;
  };
  self.prototype.toObj = function() {
    var obj = {};
    PROPS.forEach(function(prop) {
      obj[prop] = this[prop];
    }, this);
    obj.requestUri = this.requestUri;
    return obj;
  };
  self.prototype.toString = function() {
    return this.href;
  };
  return self;
})(document);

/* Main */
var out = document.getElementById('out');
var urls = [
  'https://www.example.org:5887/foo/bar?a=1&b=2#section-1',
  'ftp://www.files.com:22/folder?id=7'
];
var parser = new URLParser();
urls.forEach(function(url) {
  parser.parse(url);
  println(out, JSON.stringify(parser.toObj(), undefined, ' '), 0, '#0000A7');
});

/* Utility functions */
function print(el, text, bgColor, fgColor) {
  var span = document.createElement('span');
  span.innerHTML = text;
  span.style['backgroundColor'] = bgColor || '#FFFFFF';
  span.style['color'] = fgColor || '#000000';
  el.appendChild(span);
}
function println(el, text, bgColor, fgColor) {
  print(el, text, bgColor, fgColor);
  el.appendChild(document.createElement('br'));
}

body {
  background: #444;
}
span {
  background-color: #fff;
  border: thin solid black;
  display: inline-block;
}
#out {
  display: block;
  font-family: Consolas, Menlo, Monaco, Lucida Console, Liberation Mono, DejaVu Sans Mono, Bitstream Vera Sans Mono, Courier New, monospace, serif;
  font-size: 12px;
  white-space: pre;
}

Output

{
 "protocol": "https:",
 "hostname": "www.example.org",
 "host": "www.example.org:5887",
 "pathname": "/foo/bar",
 "port": "5887",
 "search": "?a=1&b=2",
 "hash": "section-1",
 "href": "https://www.example.org:5887/foo/bar?a=1&b=2#section-1",
 "requestUri": "/foo/bar?a=1&b=2"
}
{
 "protocol": "ftp:",
 "hostname": "www.files.com",
 "host": "www.files.com:22",
 "pathname": "/folder",
 "port": "22",
 "search": "?id=7",
 "hash": "",
 "href": "ftp://www.files.com:22/folder?id=7",
 "requestUri": "/folder?id=7"
}