Hi Robert,
Regarding your latest commit:
# TODO: find a better solution for cleaning up the name.
task_name = re.sub('[^a-zA-Z0-9-]', '', task_name)[:500]
Don't think this is a good idea:) For example I have unicode
characters in aggregation value. In this case regexp will return
nothing.
I use sha1 hash now... but there's also a little possibility of
collision
sha1_hash(self.agg_name)
def utf8encoded(data):
if data is None:
return None
if isinstance(data, unicode):
return unicode(data).encode('utf-8')
else:
return data
def sha1_hash(value):
return hashlib.sha1(utf8encoded(value)).hexdigest()
On Oct 24, 9:26 pm, Robert Kluin <robert.kl...@gmail.com> wrote:
> Hi Dmitry,
> Glad to hear it was helpful! Not sure when you checked it out last,
> but I made a number of good (I think) improvements in the last couple
> days, such as continuations to allow splitting large groups of work
> up.
>
> Robert
>
> On Sun, Oct 24, 2010 at 07:57, Dmitry <dmitry.lukas...@gmail.com> wrote:
> > Robert,
>
> > You grouping_with_date_rollup.py example was extremely helpful. Thanks
> > a lot again! :)
>
> > On Oct 14, 8:47 pm, Robert Kluin <robert.kl...@gmail.com> wrote:
> >> Hey Carles,
> >> Glad it seems helpful. I am hoping to get time today to push out
> >> some revisions and sample code.
>
> >> Robert
>
> >> On Thu, Oct 14, 2010 at 05:50, Carles Gonzalez <carle...@gmail.com> wrote:
> >> > Robert, I took a brief inspection at your code and seems very cool.
> >> > Exactly
> >> > what i was lloking for for my report generation and such.
> >> > I'm looking forward for more examples, but it seems a very valuable
> >> > addition
> >> > for our toolbox.
> >> > Thanks a lot!
>
> >> > On Wed, Oct 13, 2010 at 9:20 PM, Carles Gonzalez <carle...@gmail.com>
> >> > wrote:
>
> >> >> Neat! I'm going to see this code, hopefully I'll understand something :)
> >> >> On Wednesday, October 13, 2010, Robert Kluin <robert.kl...@gmail.com>
> >> >> wrote:
> >> >> > Hey Dmitry,
> >> >> > In case it might help, I pushed some code to bitbucket. At the
> >> >> > moment I would (personally) say the code is not too pretty, but it
> >> >> > works well. :)
> >> >> > http://bitbucket.org/thebobert/slagg
>
> >> >> > Sorry it does not really have good documentation at the moment, but
> >> >> > I think the basic example I threw together will give you a good idea
> >> >> > of how to use it. I need to do another cleanup pass over the API to
> >> >> > make a few more refinements.
>
> >> >> > I pulled this code out of one of my apps, and tried to quickly
> >> >> > refactor it to be a bit more generic. We are currently using
> >> >> > basically the same code in three apps to do some really complex
> >> >> > calculations. As soon as I get time I will get an example up showing
> >> >> > how to use it for neat stuff, like overall, yearly, monthly, and daily
> >> >> > aggregates across multiple values (like total dollars and quantity).
> >> >> > The cool thing is that you can do all of those aggregations across
> >> >> > various groupings, like customer, company, contact, and sales-person,
> >> >> > at once. I'll get that code pushed out in the next few days.
>
> >> >> > Would love to get some feedback on it.
>
> >> >> > Robert
>
> >> >> > On Tue, Oct 12, 2010 at 17:26, Dmitry <dmitry.lukas...@gmail.com>
> >> >> > wrote:
> >> >> >> Ben, thanks for your code! I'm trying to understand all this stuff
> >> >> >> too...
> >> >> >> Robert, any success with your "library"? May be you've already done
> >> >> >> all stuff we are trying to implement...
>
> >> >> >> p.s. where is Brett S.:) would like to hear his comments on this
>
> >> >> >> On Sep 21, 1:49 pm, Ben <pondneverfree...@yahoo.com> wrote:
> >> >> >>> Thanks for your insights. I would love feedback on this
> >> >> >>> implementation
> >> >> >>> (Brett S. suggested we send in our code for
> >> >> >>> this)http://pastebin.com/3pUhFdk8
>
> >> >> >>> This implementation is for just one materialized view row at a time
> >> >> >>> (e.g. a simple counter, no presence markers). Hopefully putting an
> >> >> >>> ETA
> >> >> >>> on the transactional task will relieve the write pressure, since
> >> >> >>> usually it should be an old update with an out-of-date sequence
> >> >> >>> number
> >> >> >>> and be discarded (the update having already been completed in batch
> >> >> >>> by
> >> >> >>> the fork-join-queue).
>
> >> >> >>> I'd love to generalize this to do more than one materialized view
> >> >> >>> row
> >> >> >>> but thought I'd get feedback first.
>
> >> >> >>> Thanks,
> >> >> >>> Ben
>
> >> >> >>> On Sep 17, 7:30 am, Robert Kluin <robert.kl...@gmail.com> wrote:
>
> >> >> >>> > Responses inline.
>
> >> >> >>> > On Thu, Sep 16, 2010 at 17:32, Ben <pondneverfree...@yahoo.com>
> >> >> >>> > wrote:
> >> >> >>> > > I have a question about Brett Slatkin's talk at I/O 2010 on data
> >> >> >>> > > pipelines. The question is about slide #67 of his pdf,
> >> >> >>> > > corresponding
> >> >> >>> > > to minute 51:30 of his talk
>
> >> >> >>> > > >http://code.google.com/events/io/2010/sessions/high-throughput-data-p...
>
> >> >> >>> > > I am wondering what is supposed to happen in the transactional
> >> >> >>> > > task
> >> >> >>> > > (bullet point 2c). Would these updates to the materialized view
> >> >> >>> > > cause
> >> >> >>> > > you to write too frequently to the entity group containing the
> >> >> >>> > > materialized view?
>
> >> >> >>> > I think there are really two different approaches you can use to
> >> >> >>> > insert your work models.
> >> >> >>> > 1) The work models get added to the original entity's group. So,
> >> >> >>> > inside of the original transaction you do not write to the entity
> >> >> >>> > group containing the materialized view -- so no contention on it.
> >> >> >>> > Commit the transaction and proceed to step 3.
> >> >> >>> > 2) You kick off a transactional task to insert the work model, or
> >> >> >>> > fan-out more tasks to create work models :). Then you proceed
> >> >> >>> > to
> >> >> >>> > step 3.
>
> >> >> >>> > You can use method 1 if you have only a few aggregates. If you
> >> >> >>> > have
> >> >> >>> > more aggregates use the second method. I have a "library" I am
> >> >> >>> > almost
> >> >> >>> > ready to open source that makes method 2 really easy, so you can
> >> >> >>> > have
> >> >> >>> > lots of aggregates. I'll post to this group when I release it.
>
> >> >> >>> > > And a related question, what happens if there is a failure just
> >> >> >>> > > after
> >> >> >>> > > the transaction in bullet #2, but right before the named task
> >> >> >>> > > gets
> >> >> >>> > > inserted in bullet #3. In my current implementation I just left
> >> >> >>> > > out
> >> >> >>> > > the transactional task (bullet point 2c) but I think that causes
> >> >> >>> > > me to
> >> >> >>> > > lose the eventual consistency.
>
> >> >> >>> > Failure between steps 2 and 3 just means _that_ particular update
> >> >> >>> > will
> >> >> >>> > not try to kick-off, ie insert, the fan-in (aggregation) task.
> >> >> >>> > But
> >> >> >>> > it
> >> >> >>> > might have already been inserted by the previous update, or the
> >> >> >>> > next
> >> >> >>> > update. However, if nothing else kicks of the fan-in task you
> >> >> >>> > will
> >> >> >>> > need some periodic "cleanup" method to catch the update and kick
> >> >> >>> > of
> >> >> >>> > the fan-in task. Depending on exactly how you implemented step 2
> >> >> >>> > you
> >> >> >>> > may not need a transactional task.
>
> >> >> >>> > Robert
>
> >> >> >>> > > Thanks!
>
> >> > --
> >> > You received this message because you are subscribed to the Google Groups
> >> > "Google App Engine" group.
> >> > To post to this group, send email to google-appeng...@googlegroups.com.
> >> > To unsubscribe from this group, send email to
> >> > google-appengine+unsubscr...@googlegroups.com.
> >> > For more options, visit this group at
> >> >http://groups.google.com/group/google-appengine?hl=en.
>
> > --
> > You received this message because you are subscribed to the Google Groups
> > "Google App Engine" group.
> > To post to this group, send email to google-appeng...@googlegroups.com.
> > To unsubscribe from this group, send email to
> > google-appengine+unsubscr...@googlegroups.com.
> > For more options, visit this group
> > athttp://groups.google.com/group/google-appengine?hl=en.
--
You received this message because you are subscribed to the Google Groups
"Google App Engine" group.
To post to this group, send email to google-appeng...@googlegroups.com.
To unsubscribe from this group, send email to
google-appengine+unsubscr...@googlegroups.com.
For more options, visit this group at
http://groups.google.com/group/google-appengine?hl=en.
