Web Standards Curriculum

2009-09-24T16:30:00.002+10:00

A great online course from Opera covering HTML, CSS, JavaScript and Web Standards.

Useful regular expressions

2009-09-21T16:57:00.006+10:00

Strip all HTML tags
REReplace(content,"<[^>]*>","","all")

Strip high ASCII characters (ASCII 128 and above)
REReplace(content,"[^\x00-\x7F]","","all")

Encode all ampersands that are not already encoded
REReplaceNoCase(content, "&(?!amp;)", "&", "all")

Encode all ampersands that are not part of entities
(eg. ignore  )
REReplace(arguments.content, "&(?!##?\w+;)", "&", "all")

Validate a list of numbers
REReplace(content,"[^0-9,]","","all")

Strip new lines, carriage returns and tabs
REReplace(content,"[\n\r\t]","","all")

ColdFusion performance tuning articles

2008-10-29T16:25:00.005+11:00

Coldfusion MX Tuning links by Simon Whatley
Really Fixing Applications - Are We Inside Out? from Alagad
ColdFusion Performance and Troubleshooting Guide (book)
Performance tuning for ColdFusion applications (Adobe)

Software QA and Testing Resource Center

2008-02-21T11:12:00.003+11:00

While I was looking for software to do web application load testing I came across the Software QA and Testing Resource Center. The site has lots of useful information and links, including a good list of Load and Performance Test Tools.

I ended up choosing WebLoad.

ColdFusion and MSDE 2000 on XP with SP2

2007-03-25T19:13:00.000+10:00

I set up a new PC for development at home this weekend and I ran into a (common) problem trying to get ColdFusion to work with MS SQL Server 2000 (MSDE) on XP with SP2. It took me ages but eventually I got it working. The solution was to uninstall the copy of MSDE that I originally put on and do a fresh install using SQL Server SP4 for MSDE. The setup required some parameters, eg.:
setup.exe SAPWD="your_sa_password" DISABLENETWORKPROTOCOLS=0 /L*v C:\MSDELog.log

If you can't get that to run at the command line (I couldn't) then set up a shortcut to setup.exe and put it in the target field.

New toy

2007-01-23T17:04:00.000+11:00

I got a shiny new iPod shuffle a couple of weeks ago. What's the first thing I use it for? Listening to the ColdFusion Weekly podcast on the way to work of course!

Reading Excel spreadsheet files with ColdFusion

2006-11-24T15:55:00.000+11:00

A new project I started working on requires the ability to read values from an Excel file using ColdFusion. The last time I looked into doing this (a long time ago) the answer was to use COM. Sometime soon we will be moving our production server from Windows to Solaris so that's not a great solution. After a bit of searching I came across the Apache Jakarta POI project, a Java API to access Microsoft format files. A little bit more searching revealed that ColdFusion already has this installed. After some trial and error and help from Dave Ross' blog and the API docs I got it to work.

Here's some example code to read a spreadsheet and dump it into an HTML table.


<!--- Get the file --->
<cfset FileIn = createObject("java","java.io.FileInputStream").init("#ExpandPath('myfile.xls')#")/>
<cfset fs = createObject("java","org.apache.poi.poifs.filesystem.POIFSFileSystem").init(FileIn)/>
<cfset workbook = createObject("java","org.apache.poi.hssf.usermodel.HSSFWorkbook").init(fs)/>
<!--- Get the first sheet --->
<cfset sheet = workbook.getSheetAt(0)/>
<!--- Get an iterator to loop over each row in the sheet --->
<cfset rows = sheet.rowIterator()>
<table border="1">
<!--- Process each row --->
<cfloop condition="#rows.hasNext()#">
 <tr>
 <!--- Get next row --->
 <cfset row = rows.next()>
 <!--- Get an iterator to loop over each cell in the row --->
 <cfset cells = row.cellIterator()>
 <!--- Process each cell --->
 <cfloop condition="#cells.hasNext()#">
  <!--- Get next cell --->
  <cfset cell = cells.next()>
  <!--- Get the cell value's format --->
  <cfset CellType = cell.getCellType()>
  <!--- Get the cell value --->
  <cfset CellValue = "">
  <cfswitch expression="#CellType#">
   <cfcase value="1,3">
    <cfset CellValue = cell.getStringCellValue()>
   </cfcase>
   <cfcase value="0">
    <cfset CellValue = cell.getNumericCellValue()>
   </cfcase>
  </cfswitch>
  <cfoutput><td>#CellValue# </td></cfoutput>
 </cfloop>
 </tr>
</cfloop>
</table>
<cfset FileIn.close()>

The Joel Test

2006-11-21T11:34:00.000+11:00

I've been a fan of the Joel Test for a while. Its a a quick test you can use to rate the quality of your development team (or a potential employer). If I apply the Joel test to my workplace I get a score of 3 or 4 out of 12. Hmm, obviously a bit of work still to do.

Being a web application developer I was very happy to come accross a great three part series on Drew McLellan's blog talking about applying The Joel Test to a web development setting.

Finding the most recent from multiple related records

2006-11-06T16:33:00.000+11:00

I'm currently working on a membership database. In this system people can apply to become members for a specific period and then renew their membership when that period expires. The table holding the memberships looks like this:

CREATE TABLE membership
(
MembershipId INT PRIMARY KEY AUTO_INCREMENT,
MemberId INT,
PeriodId INT,
created DATE,
FOREIGN KEY MemberId REFERENCES members
FOREIGN KEY PeriodId REFERENCES periods
)

There are also related tables to hold the member's details and the membership periods.

One of the things that the system needs to do is to display a list of members and their latest membership. My first attempt looked like this:

SELECT *
FROM membership
WHERE MembershipId IN
(
SELECT MAX(MembershipId)
FROM membership
GROUP BY MemberId
)

Whilst this works its not ideal. In the membership table the primary key really should be a composite of the MemberId and PeriodId fields. Finding the latest membership period would then require a correlated subquery based on the maximum creation date. After a bit of searching on Google I ended up with this:

SELECT *
FROM membership
WHERE membership.created =
(
SELECT MAX(membership2.created)
FROM membership AS membership2
WHERE membership2.MemberId = membership.MemberId
)

ColdFusion best practice articles and sites

2006-04-13T13:30:00.000+10:00

Updated 23 August 2006

Here are some some sites with advice and best practices in ColdFusion programming that I have found useful.

ColdFusion MX Coding Guidelines
CFC Best Practices
Top Ten Tips for Developing ColdFusion Components
CFCs - Ten Spontaneous Tips
ColdFusion Is Not A DBMS!
Open Web Application Security Project (OWASP) Top Ten security issues Project (not strictly ColdFusion but great web app security info)

Creating tables in RTF

2006-03-01T15:50:00.000+11:00

Occasionally I have to output RTF (Rich Text Format) documents from ColdFusion. For simple paragraphs of text
with basic font formatting its not that hard. Producing tables can be a bit tricky though. Here's an example of the
RTF code for a very simple document with a 3x2 table:


{\rtf1
Text before table\par
\trowd\intbl
\cellx1000\cellx2000\cellx3000
Row 1 column 1 \cell Row 1 column 2\cell Row 1 column 3\cell 
\trowd\intbl
\cellx1000\cellx2000\cellx3000
\row 
\trowd\intbl
\cellx1000\cellx2000\cellx3000
Row 2 column 1 \cell Row 2 column 2\cell Row 2 column 3\cell 
\trowd\intbl
\cellx1000\cellx2000\cellx3000
\row 
\pard 
Text after table\par
}

When viewed in an RTF editor (Word, NotePad, etc):

This example is adapted from Steve Skelton's excellent article
"How To Output RTF-formatted Documents with ASP".

CFMODULE bug

2006-02-14T13:32:00.000+11:00

Found an interesting bug in ColdFusion MX 7 today. Adding a closing backslash to CFMODULE (eg. <cfmodule template="module.cfm" />) causes the module to be executed twice.

News sources

2006-01-23T13:38:00.000+11:00

A short list of the sites I visit regularly for news. I'll update it from time to time.

Slashdot

Full As A Goog (agregator for Macromedia-related blogs)

A List Apart

Sydney Morning Herald

Joel on Software (good articles)

Storing repeating events for a calendar

2006-01-10T11:06:00.000+11:00

I have a calendar application written in ColdFusion. One of the issues that came up in development was how best to store repeating events. There seem to be two main approaches to this:

Use one database table to store information about the event and only its repeat pattern (ie. this event repeats every day/week/month/etc). You then use SQL or a programming language to dynamically calculate which days the event should appear on the calendar.

Use two tables. One stores information about the event and its repeat pattern, the other has a record for every day that an event is repeated.

The advantage of method 1 is that it takes up less storage and can handle infinitely repeating events.

The disadvantage of method 1 is that it is slow to calculate the repeats.

The advantage of method 2 is that it is very quick to retrieve and display the data.

The disadvantages are more storage required and you can't have infinitely repeating events (there are workarounds though).

This page has a good discussion of both approaches.

Speed has become an issue so I am going to implement method 2 but limit repeats to 2 years.

Upgrading Apache commons net library in ColdFusion MX 7

2005-12-08T09:42:00.000+11:00

After upgrading to ColdFusion MX 7 Enterprise a couple of weeks ago we started getting Java null pointer errors when using cfftp to list directory contents on our production server (Solaris). I did a bit of poking around and found that ColdFusion uses the Apache Jakarta commons net library for FTP functions. ColdFusion MX 7 ships with version 1.2.2 of the library and the current release is version 1.4.1 so I thought it might be worth upgrading to see if that fixed our problem.

To upgrade the library I stopped the cfusion JRun server and replaced the file {Jrun root}/servers/cfusion/cfusion-ear/cfusion-war/WEB-INF/cfusion/lib/commons-net-1.2.2.jar with commons-net-1.4.1.jar. After restarting the server cfftp worked fine.

cfheader and filenames with spaces

2005-12-05T17:11:00.000+11:00

Some time ago I had a project which required file downloads using cfheader. I found that file names with spaces were being truncated by
some browsers. Recently I came across this blog entry by
Charlie Arehart from New Atlanta which provides the solution.

Instead of

<cfheader name="Content-Disposition" value="attachment; filename=a text file.txt">

use

<cfheader name="Content-Disposition" value='attachment; filename="a text file.txt"'>

CSS form layout

2005-11-11T14:14:00.000+11:00

For a while now I've been looking for a CSS solution for laying out forms. Yesterday I was playing around
and tried using absolute positioning. This seems to work quite well across several browser/platform combinations.
I'll have to test it on more browsers but for now I'm happy. Here's an example:


<style type="text/css">
 label {
  position: absolute;
  width: 95px;
  text-align: right;
  font-weight: bold;
 }
 input, textarea, select {
  margin-left: 100px;
 }
</style>


<form action="index.cfm" method="post">

 <label for="name">Name:</label>
 <input type="text" name="name" size="30" maxlength="100"><br />

 <label for="gender">Gender:</label>
 <select name="gender">
  <option value=""></option>
  <option value="Male">Male</option>
  <option value="Female">Female</option>
 </select><br />
 
 <label for="AgeGroup">Age group:</label>
 <input type="radio" name="AgeGroup" value="1">Under 20 <br />
 <input type="radio" name="AgeGroup" value="2">21 -30<br />
 <input type="radio" name="AgeGroup" value="3">31 -40<br />
 <input type="radio" name="AgeGroup" value="4">Over 40<br />
 
 <label for="address">Address:</label>
 <textarea cols="50" rows="5" name="address"></textarea>
</form>