location.host vs location.hostname and cross-browser compatibility?

Question

Which one of these is the most effective vs checking if the user agent is accessing via the correct domain.

We would like to show a small js based 'top bar' style warning if they are accessing the domain using some sort of web proxy (as it tends to break the js).

We were thinking about using the following:

var r = /.*domain\.com$/;
if (r.test(location.hostname)) {
    // showMessage ...
}

That would take care of any subdomains we ever use.

Which should we use host or hostname?

In Firefox 5 and Chrome 12:

console.log(location.host);
console.log(location.hostname);

.. shows the same for both.

Is that because the port isn't actually in the address bar?

W3Schools says host contains the port.

Should location.host/hostname be validated or can we be pretty certain in IE6+ and all the others it will exist?

Breed

One thing to note is that google chrome has a location.origin, where MSIE and Firefox do not. developer.mozilla.org/En/Window.location - msdn.microsoft.com/en-us/library/ms952653.aspx – Plausive

See also: Whats the difference between window.location.host and window.location.hostname – Camera

possible duplicate of Whats the difference between window.location.host and window.location.hostname – Necessitous

Answer 1

As a little memo: the interactive link anatomy

--

In short (assuming a location of http://example.org:8888/foo/bar#bang):

• hostname gives you example.org
• host gives you example.org:8888

Jactitation

A picture is worth a thousand words. – Tucson

According to en.wikipedia.org/wiki/…, the port should not be consider a part of the host (but it is a part of the authority). – Microwatt

@Alec this is an interesting technical note; drilling down thru the Wikipedia citation reveals that, according to RFC 3986, "authority" ought to be the term for the concatenation of the hostname, :, and port. I wonder how much of the discussion is still available from when location.host was being formulated... I suspect it's named such today because nobody present had read or thought to mention that RFC. – Chavey

Answer 2

host just includes the port number if there is one specified. If there is no port number specifically in the URL, then it returns the same as hostname. You pick whether you care to match the port number or not. See https://developer.mozilla.org/en-US/docs/Web/API/Location for more info on the window.location object and the various choices it has for matching (with or without port).

I would assume you want hostname to just get the site name.

Krug

The links is broken now :( – Bunkmate

Use this instead: developer.mozilla.org/en-US/docs/Web/API/Window/location – Bunkmate

@Stranger - Edited my post to update the link. – Krug

Answer 3

If you are insisting to use the window.location.origin You can put this in top of your code before reading the origin

if (!window.location.origin) {
  window.location.origin = window.location.protocol + "//" + window.location.hostname + (window.location.port ? ':' + window.location.port: '');
}

Solution

PS: For the record, it was actually the original question. It was already edited :)

Sadiras

But.... OP never mentioned window.location.origin in their question. Their question was actually specifically regarding things that are not window.location.origin. – Jennifer

It's also worth noting that window.location.origin has browser compatibility issues. developer.mozilla.org/en-US/docs/Web/API/Window/… – Misname

Answer 4

Your primary question has been answered above. I just wanted to point out that the regex you're using has a bug. It will also succeed on foo-domain.com which is not a subdomain of domain.com

What you really want is this:

/(^|\.)domain\.com$/

Salema

Answer 5

MDN: https://developer.mozilla.org/en/DOM/window.location

It seems that you will get the same result for both, but hostname contains clear host name without brackets or port number.

Willpower

Answer 6

Just to add a note that Google Chrome browser has origin attribute for the location. which gives you the entire domain from protocol to the port number as shown in the below screenshot.

Sequela

Answer 7

From the mdn web docs you can see an interactive location demo where you can hover over the elements to highlight their meaning:

Sukkoth