[ic] intermittent 500 error with Link.pm

[Grant]

>>>>> My guess would be that that is happening when the client's connection is
>>>>> broken and Apache closes its filehandles that the program is writing to.
>>>>
>>>> I think you're exactly right but can I handle that scenario properly in
>>>> Link.pm so that a 500 is not produced?
>>>
>>> I'm not sure.
>>>
>>> But what do you think it should do if not a 500? It certainly isn't a 2xx
>>> result.
>>>
>>> The C-based vlink program that we normally use throws 500s in this situation
>>> too.
>>
>> Should it be an internal server error though?  It sounds like this
>> happens due to normal client activity and the server should hopefully
>> be able to handle that gracefully and return a more accurate HTTP
>> status code without bothering the error_log.
>>
>> I tried this in Link.pm but no change in error.log output:
>>
>> print @out or die "print: $!\n";
>>
> Are you using Postgresql?
>
> I built the Strap Store on Ubuntu 15.04 before it was released and I
> fixed a problem which sounds like that one by reverting back to Mysql.
> The problem was occurring specifically in a Matrix option ie only on
> pages with options displayed.


I'm using mysql with IC (and postgresql with Odoo) and I actually
don't use IC options at all.  This seems to be a pretty common issue
with apache2.  There's some discussion about it as it relates to a
different software package here:

https://github.com/eprints/eprints/issues/119

Here's how they work around it:

https://github.com/QUTlib/eprints/commit/cc46ff68c19d7251ee525842fbef391e54e269c5

- Grant