[mythtv-users] WARNING: SchedulesDirect users: server currently returning bogus results

[Robert Eden]

On 12/19/2009 11:14 PM, f-myth-users at media.mit.edu wrote:
> I note that none of the manpages for any version of tv_grab_na_dd I've managed
> to find mention anything about it returning any status at all; I
> haven't checked the code to see if it returns anything other than 0
> or 1.
I wrote _na_dd and am the maintainer.  Most (if not all) XMLTV apps 
follow the standard unix practice of exiting 0 on success something else 
on error.   Like many unix utilities, it's not always in the man page.  
You have a valid point and I'll add it to _na_dd.

I looked at my code, and appear to have run into this problem with 
_na_dd in the (distant) past.   In addition to parsing the XML, I 
search  the raw XML for <faultstring>.  If it exists, I report the error 
and die. From Tribune's point of view it makes sense; they were 
processing/transmitting data when they hit an error.  It would be 
difficult to close all the open tags so they just add the error message 
and die.  When I dealt with this before, the XML wasn't valid and I 
couldn't parse. it.

Since you use "--download-only"  my check can't help you since it 
just.... downloads the data.  If something downloaded (even with an 
embedded error) to me it's a success under --download-only. Whatever 
parses the output should check for errors just like I do when I process 
the downloaded data.

In the case of MythTV (when it reads a raw data direct formatted file),  
it appears to blow away the database before it fully parses the file, 
ensuring it's valid.  I suspect many XML errors could cause the "zero'd 
database" symptom.

The outage should not have impacted many people.  Most download at least 
7 days of data and a single days' outage *should* be tolerable.  IMHO 
you have a valid gripe with the Myth loader, not the service. (as 
history shows, we do have a pretty good track record minimizing 
outages).  Hopefully the stock Myth download behaved better and only a 
few people were impacted.  Good idea to warn the list.

Robert.