# Responding to AJAX - XMLHttpRequest

**URL:** <https://www.ruby-forum.com/t/responding-to-ajax-xmlhttprequest/133843>\
**Category:** Ruby\
**Created:** [April 4, 2008, 8:54am UTC](https://www.ruby-forum.com/t/responding-to-ajax-xmlhttprequest/133843 "2008-04-04T08:54:41Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![tonydm](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/t/e495f1/32.png) [@tonydm](https://www.ruby-forum.com/u/tonydm)\
**Post date:** [April 4, 2008, 8:54am UTC](https://www.ruby-forum.com/t/responding-to-ajax-xmlhttprequest/133843/1 "2008-04-04T08:54:41Z")

</div>

Hi all,

Perhaps someone experienced with XMLHttpRequest & ruby might be able to  
help me. I don’t know if it’s my ruby code that is failing to properly  
respond, or the javascript making the request and handling the response.  
I’ve tried just prototype, just extjs, and as you can see, a mixin of  
both as I try and figure out why I only get one response in return. The  
only way I can get all of the results found in the search (server  
script), is to build a really long string with results and pass just the  
one “combined” result. I don’t have any more hair to pull out.

tonyd

## searchlog.rb

#!/usr/local/bin/ruby -w  
require ‘cgi’

@cgi = CGI.new

# Our search params passed from our HTML page

sstring = @cgi[‘search’]  
slogtype = @cgi[‘logtype’]  
smethod = @cgi[‘method’]

# A hash of possible logs

logs = {‘smtp’ =\> ‘smtp’, ‘mail’ =\> ‘mails’, ‘mx’ =\> ‘mx’, ‘spam’ =\>  
‘spam’, ‘Dial Up’ =\> ‘radius’, ‘DHCP’ =\> ‘dhcp’ }

# Send Response

def send\_response(wts)  
@cgi.header { “Content-Type: text/html” } # Not sure if this is  
correct - Content? necessary?  
@cgi.out{ “#{wts}” }  
end

…  
…

# Search through the log

File.open(“/var/log/#{logs[slogtype]}”,  
‘r’).grep(/#{search\_string}/).each do |line|

# This works but is not “live”…

response = response \<\< “#{line}  
” # append to response string

# This dosen’t work - The end result is I only get one response back

at my javascript call  
send\_response( “#{line}  
” ) # send response for each result  
end

send\_response( response ) # This in conjunction with building of  
response string

…  
…

## searchlog.js

// Extjs JS Lib - [extjs.com](http://extjs.com)  
Ext.onReady(function(){

// Disable the ENTER key from submitting the form  
Ext.get(‘getinfo’).on({  
submit:function(e){  
e.preventDefault();  
return false;  
}  
});

// Handle form submission  
Ext.get(‘submitButton’).on(‘click’, function(){  
var pars = Form.serialize(‘getinfo’);  
var url = ‘/cgi-bin/search.rb’  
ajaxUpdate(pars, url);  
});

});

function ajaxUpdate(pars, url) { [//Prototype.js](https://Prototype.js) function  
var ajax = new Ajax.Updater({success: ‘results-div’, failure:  
‘results-div’}, url, {  
method: ‘get’,  
parameters: pars,  
encoding: ‘UTF-8’,  
insertion: Insertion.Bottom,  
});  
}

---

<div class="post-metadata">

**Author:** ![tonydm](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/t/e495f1/32.png) [@tonydm](https://www.ruby-forum.com/u/tonydm)\
**Post date:** [April 4, 2008, 9:07am UTC](https://www.ruby-forum.com/t/responding-to-ajax-xmlhttprequest/133843/2 "2008-04-04T09:07:55Z")

</div>

One thing to note is that it is expecting a Content-Type of  
application/json as well as the content to be in actual JSON format.  
You can simply require ‘json’ and call wts.to\_json which should be  
sufficient for your needs.

You might consider looking at Rack for building your tiny web app and  
just proxy some address to it; it really cleans up handling requests  
and not needing CGI, but your solution does work fine and avoids a  
problem with AJAX requests failing due to cross-server requests (which  
is what requests not on port 80 are considered).

Matt T.

---

<div class="post-metadata">

**Author:** ![tonydm](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/t/e495f1/32.png) [@tonydm](https://www.ruby-forum.com/u/tonydm)\
**Post date:** [April 4, 2008, 9:28am UTC](https://www.ruby-forum.com/t/responding-to-ajax-xmlhttprequest/133843/3 "2008-04-04T09:28:28Z")

</div>

Matt T. wrote:

> One thing to note is that it is expecting a Content-Type of  
> application/json as well as the content to be in actual JSON format.  
> You can simply require ‘json’ and call wts.to\_json which should be  
> sufficient for your needs.
> 
> You might consider looking at Rack for building your tiny web app and  
> just proxy some address to it; it really cleans up handling requests  
> and not needing CGI, but your solution does work fine and avoids a  
> problem with AJAX requests failing due to cross-server requests (which  
> is what requests not on port 80 are considered).
> 
> Matt T.

Hey Matt,

Thanks for the awesome quick reply. I’ll dig into that. That’s the  
first I heard of this from any blog or forum. But there’s some sense to  
what you say. I’ve got to get ruby\_json on my freebsd server. I’ll let  
you know how it goes. Thanks!

tonyd

---

<div class="post-metadata">

**Author:** ![tonydm](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/t/e495f1/32.png) [@tonydm](https://www.ruby-forum.com/u/tonydm)\
**Post date:** [April 4, 2008, 10:06am UTC](https://www.ruby-forum.com/t/responding-to-ajax-xmlhttprequest/133843/4 "2008-04-04T10:06:01Z")

</div>

Tony De wrote:

> Matt T. wrote:
> 
> > One thing to note is that it is expecting a Content-Type of  
> > application/json as well as the content to be in actual JSON format.  
> > You can simply require ‘json’ and call wts.to\_json which should be  
> > sufficient for your needs.
> > 
> > You might consider looking at Rack for building your tiny web app and  
> > just proxy some address to it; it really cleans up handling requests  
> > and not needing CGI, but your solution does work fine and avoids a  
> > problem with AJAX requests failing due to cross-server requests (which  
> > is what requests not on port 80 are considered).
> > 
> > Matt T.
> 
> Hey Matt,
> 
> Thanks for the awesome quick reply. I’ll dig into that. That’s the  
> first I heard of this from any blog or forum. But there’s some sense to  
> what you say. I’ve got to get ruby\_json on my freebsd server. I’ll let  
> you know how it goes. Thanks!
> 
> tonyd

Ok, got json installed. Making some changes, I still get just the one  
reponse. It is, however, passing additional data…  
Before: …data…  
Now: “…data…”\n

Firebug Header info: (Maybe useful for you to help me troubleshoot)

Response Headers  
Date Fri, 04 Apr 2008 07:46:24 GMT  
Server Apache/2.2.0 (FreeBSD) mod\_ssl/2.2.0 OpenSSL/0.9.7e-p1 DAV/2  
mod\_perl/2.0.2 Perl/v5.8.8  
Content-Length 159  
Keep-Alive timeout=5, max=100  
Connection Keep-Alive  
Content-Type text/html

Request Headers  
Host [www.myserver.net](http://www.myserver.net)  
User-Agent Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.12)  
Gecko/20080201 Firefox/2.0.0.12  
Accept text/javascript, text/html, application/xml, text/xml, _/_  
Accept-Language en-us  
Accept-Encoding gzip,deflate  
Accept-Charset ISO-8859-1,utf-8;q=0.7,\*;q=0.7  
Keep-Alive 300  
Connection keep-alive  
X-Requested-With XMLHttpRequest  
X-Prototype-Version 1.6.0.2  
Referer [myserver.net](http://www.myserver.net/searchlog.html)  
Authorization Basic dGVjaDp0M2No

## searchlog.rb

#!/usr/local/bin/ruby -w  
require ‘rubygems’  
require ‘json’  
require ‘cgi’

@cgi = CGI.new

# Our search params passed from our HTML page

sstring = @cgi[‘search’]  
slogtype = @cgi[‘logtype’]  
smethod = @cgi[‘method’]

# A hash of possible logs

logs = {‘smtp’ =\> ‘smtp’, ‘mail’ =\> ‘mails’, ‘mx’ =\> ‘mx’, ‘spam’ =\>  
‘spam’, ‘Dial Up’ =\> ‘radius’, ‘DHCP’ =\> ‘dhcp’ }

# Send Response

def send\_response(wts)  
@cgi.out{ wts.to\_json }  
end

…  
…

# Search through the log

@cgi.header { “Content-Type: application/json” } # Send only the one  
header back (made no diff to include with each response)  
File.open(“/var/log/#{logs[slogtype]}”,  
‘r’).grep(/#{search\_string}/).each do |line|  
send\_response( “#{line}  
” ) # send response for each result  
end