September means summer is over and we all get back to work or back to school.
And for those of us who have been out of school for a very long time, I hope you always look for opportunities to learn something new. Send me your questions if you get stuck!
Q:I have a CF Scheduler question: How do I schedule the execution of a template to run at 6 a.m. on weekdays (Mon-Fri) only? I know how to schedule it at 6 a.m. every day, but I don't want it to run on Saturday or Sunday. Any suggestions?
A:Unfortunately, there's no way to get the CF Scheduler to do this for you (at least none that I'm aware of). There is, however, an easy way to accomplish this. Schedule the template to run at 6 a.m. every day, which you already know how to do, but put a CFIF block in your template to test for the day of the week. If the current day is a Saturday or Sunday, don't execute the code. The template is still executed by the scheduler, but none of the code executes on those days. Here's the code you need to wrap around the existing code in your page:
<CFIF DayOfWeek(Now()) gt 1 AND DayOfWeek(Now()) lt 7>
...this will only run Mon-Fri!
</CFIF>
Q: I want to assign a user a password using a randomly generated string of letters and numbers without repeating any characters. How can I do this?
A: Great question. The solution is in the following code. Let's assume that the password will be eight characters long using both letters and numbers. First, assign a variable that contains all the possible characters (I like to omit the letters "L" and "O" because they're often confused with the numbers 1 and 0). Next, initialize your password to null. Then loop from 1 to 8. For each iteration of the loop, pick a random number between 1 and the length of your character list. Select the character from the list based on the random number and append it to the password. Last, delete that character from the list so it won't get picked again.
<CFSET charList =
"a,b,c,d,e,f,g,h,i,j,k,m,n,p,q,r,s,t,u,v,w,x,y,z,0,1,2,3,4,5,6,7,8,9">
<CFSET Password = "">
<CFLOOP FROM="1" TO="8" INDEX="i">
<CFSET RandNum = RandRange(1,ListLen(charList))>
<CFSET Password = Password & ListGetAt(charList,RandNum)>
<CFSET charList = ListDeleteAt(charList,RandNum)>
</CFLOOP>
<CFDUMP VAR="#Password#">
Q: We recently received an e-mail from one of our customers explaining that attaching the following code (mode= debug) to the URL of a ColdFusion file (for example, listings.cfm? mode=debug) will reveal most, if not all, of our network information (IP address, server information, OS information, etc). Obviously, this is a potential security threat and has shaken us. What can we do about it?
A:It's funny (ironic) that when this was first introduced (in version 4, I think), it was actually billed as a "feature"! Appending "?mode=debug" to the URL does reveal the execution time of a page and all of the Form, URL, and CGI variables that were available to the page when it was processed. At times when debugging an application it's helpful to a developer to get this info on-the-fly by applying this URL string. But, as you mention, it can be very dangerous to your site if a good hacker gets this information! Fortunately, you can prevent this from happening by placing one line of code in your Application.cfm file:
<CFSETTING SHOWDEBUGOUTPUT="No">
With this tag in Application. cfm, nobody (including yourself) will be able to see any of this debug information. When developing an application, I leave this setting set to "Yes," but when I put the application into production, I set it to "No."
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