How can I obtain the hostname or address of my .js script from inside the .js script?

I have a web site which downloads the same script from any number of different servers:

<script type="text/javascript" src="http://server1.example.com/hello.js"></script>
<script type="text/javascript" src="http://server2.example.com/hello.js"></script>
<script type="text/javascript" src="http://server3.example.com/hello.js"></script>
<script type="text/javascript" src="http://server4.example.com/hello.js"></script>

Each script has a locally-scoped vari开发者_JS百科able which has to be the hostname of the server that script was downloaded from: so when I download the script from server1.example.com that variable's value has to be server1.example.com.

Can this be done with absolutely no server-side programming? (AJAX requests can be sent, but the solution cannot include any server-side code)

Please note that I am looking for the host which the script is hosted on, not the host of the current browser page; that means I am not looking for window.location.

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I think the below code can help:

var scripts = document.getElementsByTagName('script');
for(var a = 0; a < scripts.length; a++){
    if(scripts[a].src.indexOf('<<<--###-->>>') > 0 ) 
        var ThisScriptPath = scripts[a].src.substr( 0, scripts[a].src.lastIndexOf('/'));
}

You will need to replace the <<<--###-->>> with your script's name, and you will have the path stored in ThisScriptPath (remember to use the final slash)

Tip: Use an alert to check the results before getting into production

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You can extract from window.location.host the first part of the domain name with regex.

You can use that in order to extract the first part

var host = window.location.host;
host = host.match(/^[\d\w]+/);