[ZODB-Dev] read-only database

[Nathan Van Gheem]

BTW, I thought I could just use the ZPublisherEventsBackup to abort
every transaction when zope is in read-only... Kind of hacky, but not
too bad :)

On Mon, Sep 27, 2010 at 12:24 PM, Nathan Van Gheem <vangheem at gmail.com> wrote:
>> Can you rephrase that with fewer "not"s?  I'm not quite sure what you're
>> asking...
> :) Yes. We would like our read-only zodb to still serve pages even if
> plone tries to write to the database. Basically, we'd like to suppress
> the read-only errors you get when you try to write to a read-only
> database.
>
>> It would be much safer to fix Zope/Plone application than to monkey
>> around with silently working around the readonly aspects of the
>> database. especially since you are already putting the database
>> into a readonly mode.
>> again, we are doing this fine in production.  so it must be something
>> in your application causing writes.
> We've seen issues where a scale wasn't generated for some reason,
> archetypes trying to write a field value when calling the get
> accessor, writes occurring when simply calling context.objectValues()
> and other ones I haven't figured out yet. They aren't on a majority of
> the pages, but it's enough to be very annoying.
>
> Even if we were able to fix everything, I'd still rather not wait for
> us to find something else that is a problem.
>
> Thanks for the discussion though. I appreciate the feedback.
>
>
> -Nathan
>
> On Mon, Sep 27, 2010 at 12:12 PM, Alan Runyan <runyaga at gmail.com> wrote:
>>> We're currently deploying plone with zrs which replicates to read-only
>>> databases which is what actually gets served to the user. It works
>>> fine in most cases, but there seem to be odd issues here and there
>>> where plone will try to write to the database and will throw an error
>>> on the page load.
>>
>> We have read only Plone's in production and this works fine.
>> Please enumerate the problems on a plone ticket, dev.plone.org
>> (mention your py, zope, plone versions).
>>
>>> Is there anyway to get it to not error out and not simply silently not
>>> write to the database?
>>
>> It would be much safer to fix Zope/Plone application than to monkey
>> around with silently working around the readonly aspects of the
>> database. especially since you are already putting the database
>> into a readonly mode.
>>
>> again, we are doing this fine in production.  so it must be something
>> in your application causing writes.
>>
>> cheers
>> alan
>>
>