Variable Datasource is undefined - coldfusion

Question

I have defined a datasource in the admin console of ColdFusion Admin. I have declared the configuration with the same datasource name in set_datasource_util file. I have a webpage that connects to a DB(Oracle) using the datasource given and it works fine most of the time. But lately I am starting to see exceptions like "Variable datasource-name(my app name) is undefined". I am not able to identify the root cause as I am not able to recreate it as it works most of the time. I can say on average on 1000 hits of page, it fails 1 time with that exception. Can anyone help in identifying what could be the possible issue so that I can investigate in that direction.
I have configured WOCD080P_ABC in CFAdmin.
Below is the code from Application.cfm
<cfif client.securityLevel NEQ ''>
<cfinvoke component="#siteroot#.CFC.Set_Data_Source_Util" method="fnSetABCDataSource" returnvariable="ABCDataSourceDefinition">
<cfinvokeargument name="Environment" value="#variables.thisServerType#" />
</cfinvoke>
<cfif ABCDataSourceDefinition.DataSource NEQ 'Error'>
<cfset DATASOURCE_ABC = ABCDataSourceDefinition.DataSource />
<cfset DBUSER_ABC = ABCDataSourceDefinition.DBUser />
<cfset DBPASSWORD_ABC = ABCDataSourceDefinition.DBPassword />
</cfif>
</cfif>
Below is the code from Set_datasource_UTil :
<cffunction name="fnSetABCDataSource" access="public" returntype="struct">
<cfargument name="Environment" type="string" required="yes">
<cfset ReturnParameters = StructNew() />
<cfif Environment IS 'prod'>
<cfset ReturnParameters.DataSource = 'WOCD080P_ABC' />
<cfset ReturnParameters.DBUser = ''/>
<cfset ReturnParameters.DBPassword = '' />
<cfelse>
<cfset ReturnParameters.DataSource = 'WOCD080T_ABC'/>
<cfset ReturnParameters.DBUser = ''/>
<cfset ReturnParameters.DBPassword = '' />
</cfif>
<cfreturn ReturnParameters>
</cffunction>
Below is the code which i am executing from HTML file.
<cfinvoke component="#siteroot#.cfc.ABC_UTIL" method="GetRegion" returnVariable = "USregion" >
<cfinvokeargument name="dbSource" value=#DATASOURCE_ABC# />
<cfinvokeargument name="dbUser" value=#DBUSER_ABC# />
<cfinvokeargument name="dbPass" value=#DBPASSWORD_ABC# />
</cfinvoke>
The code in the HTML file works most of the time but breaks sometime with error Variable DATASOURCE_ABC not defined.
Any help appreciated.

Answer 1

Please ensure you are using the var keyword for local variables inside of CFC Functions:
<cfset var ReturnParameters = StructNew() />
CF9+ local scope can be used in lieu of var:
<cfset local.ReturnParameters = StructNew() />
For extra protection, improve this statement in your application.cfm:
<cfif isDefined("ABCDataSourceDefinition.DataSource")
AND ABCDataSourceDefinition.DataSource NEQ 'Error'>
<cfset DATASOURCE_ABC = ABCDataSourceDefinition.DataSource />
<cfset DBUSER_ABC = ABCDataSourceDefinition.DBUser />
<cfset DBPASSWORD_ABC = ABCDataSourceDefinition.DBPassword />
</cfif>
Also, the could be another source of why a datasource is not being defined. I assume you have an interceptor that catches that before this datasource error occurs and sends them to a login page or something.