Greetings, I've identified a somewhat minor but possibly damaging bug in CF 5. It's pretty strange, but true. Zac Belado has confirmed that this was also the problem in his case (see his "Page Processing Twice" message from earlier today). It seems to only affect CF5 (4.5 was also tried) but so far only tested on W2K.
The bug causes a template to be executed twice by the CF engine. It literally runs everything connected to the request twice (all includes, parent template, etc). There is no indication of this unless you have data that is noticeably affected (such as inserting DB records). The HTTP request is not doubled, only the actual CF code execution. This is not browser or Web server-related in any way. The cause seems to be missing cfoutput tags around a variable call, and apparently specifically in an IMG tag (some others were tried with no problems surfacing). So some code like this: <img src="#variables.someVariable#/test.gif"> (w/out cfoutput tags anywhere around it) will cause double execution. Wrap it in cfoutputs (or in comments) and the problem goes away. Strange, no? So strange that I wrote a test for this. I've pasted my test template below, but if your email client makes it unreadable then you can also download a version here <http://www.WorldDesign.com/CF/BugTest.cfm.txt>. Instructions are in the comment. I'll also submit this to MM. Comments welcome. Cheers, -Max BugTest.cfm ------------------- <!--- This test template demonstrates an apparent bug in ColdFusion v.5 that causes a template to be executed twice per request. Run this template and look for a file named BugTestLog.txt in the same folder as the template. It should have 2 entries with exact same date/time stamp every time you request this template. As you can see there is no HTTP redirection/reload involved and the browser only requests the template once (check your web server log to verify). There is apparently no way to tell that the execution is happening twice except by looking at external events (like the log file double entry in this example). The cause seems to be missing cfoutput tags around a variable call, and apparently specifically in an IMG tag (some others were tried with no problems surfacing). Putting cfoutput or CF comment tags around the variable call will solve the issue (try it and then check the log file -- you should now only see one time stamp per request). So far this has only been confirmed on CF5 with Windows 2000. CF 4.5 on NT4 was also tried and did not exhibit this behavior. [EMAIL PROTECTED] 12/10/01 ---> <cfset logDir = GetDirectoryFromPath(GetCurrentTemplatePath())> <cfset logFile = logDir & "BugTestLog.txt"> <cflock timeout="5" throwontimeout="Yes" name="writeTestLogFile" type="EXCLUSIVE"> <cffile action="APPEND" file="#logFile#" output="Ran at #Now()#" addnewline="Yes"> </cflock> <cfset someVariable = "test"> <!--- the presence of the following line without cfoutput tags around it will cause this template to execute twice ---> <img src="#variables.someVariable#/test.gif"> ----------------------------- Maxim Paperno, CTO World Design Group, Inc. [ CF Development and Hosting since 1996 ] <http://www.WorldDesign.com/> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Structure your ColdFusion code with Fusebox. Get the official book at http://www.fusionauthority.com/bkinfo.cfm FAQ: http://www.thenetprofits.co.uk/coldfusion/faq Archives: http://www.mail-archive.com/cf-talk@houseoffusion.com/ Unsubscribe: http://www.houseoffusion.com/index.cfm?sidebar=lists
