Why is CFTHREAD not running query and creating a file?

I have a function that should check the date of a file. If the file is greater than sixty seconds, a query should run and create a new file. The query takes sixty seconds to run.

This process works perfectly when it's not wrapped in a CFTHREAD. When CFTHREAD is used, nothing seems to happen. I get no errors. What I expect to see, is a new file being made. I never see that new file.

Where should I look for an error? What am I missing? Why is CFTHREAD not working?

<!--- GET CATEGORIES --->
<cffunction name="getCategories" access="remote">
    <cfscript>
        LOCAL.MaxFileAge = 60;
        LOCAL.MaxFileUnits = 's';

        // THE FILE
        LOCAL.TheFileDaily = "#VARIABLES.JSDir#\#VARIABLES.DayMonth#-categories.json";

        // THE FILE DOES NOT EXIST
        if (fileExists(LOCAL.TheFileDaily) == false) {
            LOCAL.MakeNewFile = true;
        // THE FILE EXISTS
        } else {
            // GET THE DATE OF THE FILE
            LOCAL.LastModified = getFileInfo(LOCAL.TheFileDaily).LastModified;
            // GET FILE AGE
            LOCAL.FileAge = dateDiff(LOCAL.MaxFileUnits, LOCAL.LastModified, now());
            // FILE IS OLD
            if (LOCAL.FileAge > LOCAL.MaxFileAge) {
                LOCAL.MakeNewFile = true;
            } else {
                LOCAL.MakeNewFile = false;
            }
        }
    </cfscript>
    <cfif LOCAL.MakeNewFile eq true>
        <cfthread action="run" priority="HIGH">
            <cfquery name="Q">
                SELECT  Stuff
                FROM    Tables
            </cfquery>
            <!--- MAKE THE DAILY FILE --->
            <cffile action="write" file="#LOCAL.TheFileDaily#" output="#serializeJSON(Q)#">
        </cfthread> 
    </cfif>
</cffunction>

Solution

You can't write to and share the local scope to a seperate thread, you need to share them via the request scope (request is the ideal scope for this as developers have very tight control over what data is contained within). You might try something like this:

Create a struct within the request scope and write to that.

In fairness, only variables you need to transfer need be in the request scope's struct. This is just a generic update because I don't know what the contents of your CFTHREAD really looks like. In this case, it actually looks like TheFileDaily is the only variable you're sharing, so that would be the only thing that needed to be in the request scope.

<!--- GET CATEGORIES --->
<cffunction name="getCategories" access="remote">
    <cfscript>
        request.lData = StructNew();
        request.lData.MaxFileAge = 60;
        request.lData.MaxFileUnits = 's';

        // THE FILE
        request.lData.TheFileDaily = "#VARIABLES.JSDir#\#VARIABLES.DayMonth#-categories.json";

        // THE FILE DOES NOT EXIST
        if (fileExists(request.lData.TheFileDaily) == false) {
            request.lData.MakeNewFile = true;
        // THE FILE EXISTS
        } else {
            // GET THE DATE OF THE FILE
            request.lData.LastModified = getFileInfo(request.lData.TheFileDaily).LastModified;
            // GET FILE AGE
            request.lData.FileAge = dateDiff(request.lData.MaxFileUnits, request.lData.LastModified, now());
            // FILE IS OLD
            if (request.lData.FileAge > request.lData.MaxFileAge) {
                request.lData.MakeNewFile = true;
            } else {
                request.lData.MakeNewFile = false;
            }
        }
    </cfscript>
    <cfif request.lData.MakeNewFile eq true>
        <cfthread action="run" priority="HIGH">
            <cfquery name="Q">
                SELECT  Stuff
                FROM    Tables
            </cfquery>
            <!--- MAKE THE DAILY FILE --->
            <cffile action="write" file="#request.lData.TheFileDaily#" output="#serializeJSON(Q)#">
        </cfthread> 
    </cfif>
</cffunction>

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