WebDevelopment, ColdFusion, Railo, JS, Database and Tech-related by the Co-Founder and CEO of tunesBag.com

Monday, 24 September 2007

Upload files to Webserver using WebDAV

WebDAV is a cool alternative to FTP and due to it's HTTP-basis, the typical port / passive problems of FTP can be ignored. Since version 7, ColdFusion support a huge range of the WebDAV commands, including TRACE, OPTIONS and so on.
To put a file to an enabled server, you simply have to use the following code:

cfhttp method="PUT" url="http://Server/Directory/Filename" username="username" password="password" throwonerror="true" cfhttpparam type="header" name="Content-Type" value="content/type"
cfhttpparam type="file" name="file" file="#a_str_full_path_of_filename#"
Don't forget to check the cfhttp response for possible errors!

Thursday, 13 September 2007

Avoid locking of session variables

In most of our applications, session variables are just used for holding a structure with security information (aka securitycontext). As locking is essential (and not locking can lead to some terrible headache) all readings and writes must be protected (especially if race conditions could occur).
So our approach is to copy the securitycontext on each request into the request scope using the following code:
Application.cfc / onRequest
cflock scope="session" timeout="30" type="readonly"
cfset a_struct_securitycontext=" Duplicate(session.a_struct_securitycontext)"

(Of course a check is needed if the securitycontext exists at all ;-)).
Using this way the structure can be accessed without any locking - very important to mention is the Duplicate function because we want a deep copy and not just a reference to the original structure. Be aware of this fact, because the request structure will not change until the next request is executed!

jQuery 1.2 released

Yeasterday a new version of jQuery has been released (1.2). If you ever have to deal with JavaScript in your application in a professional way, give this library a try. It's sooo smooth and I prefer this one very very much over prototype.

So, what's the big deal of this tiny (22kb) little .js file?
The design of the library is just gorgeous. The basic principle is very simple:
  1. Select the desired objects
  2. Perform some action on them
Sounds simple, hmm? The power of the system can be shown in some short example:
In this case an object with the ID this_is_the_id is selected and hidden.

$("#orderedlist > li").addClass("blue");
I this example, the CSS class "blue" is added to all child elements of an ordered list.

$(document).ready(function() {

Here some code can be placed which is executed as soon as the DOM structure of the document has finished loading - so no more onLoad events which can have a huge delay because of e.g. external images or advertising stuff.

Here you can find some more tutorials on this.

Thanks to Ben for his posting about the new release. He also mentions his fear about getting lazy in writing real hardcore JS stuff, but my opinion is goes ahead with the the jQuery credo in this case: Write less, do more!

Wednesday, 12 September 2007

Welcome to my new ColdFusion Blog

My nams is Hansjoerg Posch and I am developing Web Applications in ColdFusion for more than four years now. In this blog I will post about interesting stuff, new technologies and give you some tipps and insights on my current work at InBox.cc.
Feel free to comment any articles!

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