Possible to get Duplicate Job Numbers?

Netsmart

Hi,

  We came across a possible
issue today.  We send faxes from a queue,
and they often go out very quickly.  This
is a log where you can see that three of them went out in the same second.  When we get the Job Number from the Submit, I
write it to a database record and to a log. 
This job number is later used to check status.  What we found today is that it looks like
the same job number was returned for two different fax submits.

This is from our log… note the time stamps.

First submit:

2012-03-30 18:07:27.9398 [Info] FaxNumber=15202901650, From=CODAC, To=W

2012-03-30 18:07:28.3930 [Info] EasyLink JobNumber:xsi: 11046288

 

Second submit in the
same fraction of a second.  In this case the Job Number is different from the one above.

2012-03-30 18:07:28.3930 [Info] FaxNumber=15202901701, From=La Frontera, To=W

2012-03-30 18:07:28.9555 [Info] EasyLink JobNumber:xsi: 11046304
(MyFaxWindowsService.EasyLink.SendFax)

 

Third submit, this is
still in the same fraction of a second, and it has the same Job Number as the
previous one.

2012-03-30 18:07:28.9711 [Info] FaxNumber=15203264317, From=La Frontera, To=W

2012-03-30 18:07:29.2992 [Info] EasyLink JobNumber:xsi: 11046304 (MyFaxWindowsService.EasyLink.SendFax)

 

Is it possible that we are getting the same Job Number
returned on two submits? 

Thanks, David

skamens

Yes, it is definitely possible to receive duplicate job numbers back from a submission.  This is all related to the MessageId specified in your API input.

The MessageId is intended to be a user-created string that uniquely identifies a job from the sender's side.  The system maps this value to the jobs on the system, and when a job with a matching MessageId is found, the prior job number is returned.  This helps to prevent duplicate jobs when there is some sort of glitch between the your system and ours (such as a network issue).

In your case, the MessageID has the form: INFOCOM3/30/2012 6:07:28 PM, so as you figured out, if you do submit multiple jobs in the same second, you will have a MessageId clash and wind up getting duplicate job numbers.

The MessageId must not only be unique among all of your jobs, but also unique throughout our entire system.  We recommend that you prefix your MessageId with your user ID (which may be the case here anyway).  To make your MessageID's unique, there are various time functions that will give you time at the microsecond level, or you could use some sort of internal message counter along with the date/time.