Javascript/Cgi communication - Logging Browser info

p

Hey there,

If I wanted to log info about browser's version/os/resolution how would I go about it.

I know you can check some things with the HTTP_AGENT env variable, but I want to check things like resolution and any other things I can think of to get a decent idea of who's viewing the site.

Is this usually done with javascript, and if so, how is it done. (:

Thanks,

- Kevin

Bard

thecounter.com might be of some help to you...

dahamsta

Yeah, there's very little information you can get about the client side without using client-side scripting. It's pretty easy to do though, you just sniff them with JavaScript and pass them to a server-side script. You can do that in one of three ways - slot the variables into a form and have the user submit it (or submit it programmaitically); slot them into a QUERY_STRING and redirect; or slot them into cookies and retrieve them on the next page load.

Without knowing what kind of server-side language you're using and what the application is, I couldn't give you any details though (I'm not going through all of 'em ).

adam

p

I basically just want to run a little counter on my page.
I want to write it myself though.

Language would probably be Perl or PHP.

I imagine the techniques are pretty similar.

Someone else suggested to me simply having javascript use an image tag to pass info to a CGI and return a simple 1x1 pixel image. I think that looks like the best idea at present.

- Kevin

The Corinthian

You don't need anything done client-side (with JavaScript) as you can grab all the environment variables from the request variables sent to the server.

In Perl you can get a list of the available request headers thus:

#!/usr/local/bin/perl

print "Content-type: text/htmlnn";
foreach $env_var (keys %ENV) {
print "<BR>$env_var is set to $ENV{$env_var}";
}

While in PHP you can get most information using the phpinfo() function (you can do a foreach too, just can't remember what the array is called).

How you write this (as a false image or just an SSI) and how you intend to record your data (concurrency issues, etc.), I'll leave up to you.

Hope this helps.

---

"Just because I'm evil doesn't mean I'm not nice." - Charlie Fulton

dahamsta

<font face="Verdana, Arial" size="2">Originally posted by The Corinthian:
You don't need anything done client-side (with JavaScript) as you can grab all the environment variables from the request variables sent to the server.</font>

Not client-side environment variables though Corinthian, like screen width and height, and resolution.

adam

The Corinthian

<font face="Verdana, Arial" size="2">Originally posted by dahamsta:
Not client-side environment variables though Corinthian, like screen width and height, and resolution.</font>

Upps, fair enough. Most things you won't need anything client-side, screen width and height, and resolution you regrettibly do (I wasn't reading the post carefully enough) - in which case use something based on this:

if (document.all) {
    height = document.body.offsetHeight;
    width = document.body.offsetWidth;
    browser = "Internet Explorer";
} else if (document.layers) {
    height = window.innerHeight;
    width = window.innerWidth;
    browser = "Netscape";
}
document.write("Browser: " + browser + "<br>");
document.write("height: " + height + "<br>");
document.write("width: " + width);

And send it back to the server as a POST or GET.

---

"Just because I'm evil doesn't mean I'm not nice." - Charlie Fulton