…and now for my Glorp on VAST error handling rant.


I’ve written in my previous post about a debugging session that took longer than necessary for two reasons: my stupidity and a combination of several unfriendly factors. So let’s continue our journey up through my walkback of today’s image crash.

Once I figured there was no Seaside problem in the crash, I scrolled further up through the walkback and what I found there really made me upset about the error handling in Glorp (I was also upset about myself and the fact that I had just spent an hour for nothing). Just about 1500 lines towards the top of the walkback was this:

ExceptionalEvent>>#signalWith:
  receiver = Exception: Database error
  arg1 = AbtError:  rc=-1 for '57016' in an AbtIbmCliCSDatabaseConnection at (12.12.2012 11:25:20)  '[SQ
LSTATE=57016 - [IBM][CLI Driver][DB2/LINUXX8664] SQL0668N  Operation not allowed for reason code "7" on 
table "MYTABLE".  SQLSTATE=57016
 [Native Error=-668]]
'
[] in VADatabaseAccessor>>#loginIfError:
  receiver = a VADatabaseAccessor
  blockarg1 = AbtError:  rc=-1 for '57016' in an AbtIbmCliCSDatabaseConnection at (12.12.2012 11:25:20)  '[SQLSTATE=57016 - [IBM][CLI Driver][DB2/LINUXX8664] SQL0668N  Operation not allowed for reason code "7" on table "MYTABLE".  SQLSTATE=57016
 [Native Error=-668]]
'

Holy Moly! So this was the cause of my problem. I had altered MYTABLE in some schema migration routine and the table needed reorg. This is easy to handle once you know it needs to be done: fire up some DB2 client and do a REORG TABLE MYTABLE.

But what is Joachim complaining about? It’s his job to know what he did to the database, not Glorp’s…

I am complainning about the fact that Glorp simply obfuscates a very clear error message. Remember what the walkback started with? If you forgot, here are the first lines of the walkback:

Walkback at 11:25:20 on 12.12.2012
Database error: 
    [] in AbtHeadlessRuntimeStartUp class>>#outputWalkback:process:  
    ...etc...

That’s what I am complaining about. I could have fixed the problem in just three minutes if the walkback told me what’s wrong.
DB2 tries hard to tell the stupid programmer what’s the problem. AbtIbmCliDatabaseConnection>>#fetchNextRowFromCursor:ifError: hands this exception on to its caller, and Glorp (or better, the VAST port of it) simply takes that message and puts it into the dustbin or keeps it as a secret. Eat this, programmer!

This is due to some strange error handling code that comes from the original Glorp implementation. It has to be adopted to VAST, because the adaptation that was done in the original Glorp code is defunct. I tried to fix that on my more than once, but only found another problem in VAST that completely befuddled me so I gave up. Whatever I tried, something didn’t work. That problem can be fixed very easily, and I think it will be integrated into VAST soon, but it isn’t yet.

So this is my rant about the current VA ST Glorp port and its error handling mess. Other than that, I must say Glorp is stable and works very well, even if the VAST version is a few versions behind.

Ah, before I forget it: After a reorg of the table it seems my application runs fine and I am in the middle of testing and fixing.