diary-23aug2013.md

23 Aug 2013

Bug I reported a while back

I reported a bug a while ago about "GnomeKeyring errors when installing devstack":

https://bugs.launchpad.net/devstack/+bug/1193164

Some Tempest and Keystone developers made some comments about how to address this issue long-term in bug fixes.

Code review

Reviewed litong01's patch "install manual last few sections format needs to be fixed"

https://review.openstack.org/#/c/43499/

and made a comment about documentation

Building Ceilometer documentation

To review litong01's patch, I tried to build the Ceilometer documentation by going to the doc directory and running the Makefile:

$ cd /opt/stack/ceilometer/doc
$ make html

But this failed because I didn't have all the dependencies installed.

To install the dependencies, I did

$ sudo pip install sphinxcontrib-httpdomain
$ sudo pip install sphinxcontrib-pecanwsme
$ sudo pip install oslo.sphinx

Group by blueprint

• group by blueprint on Launchpad: https://blueprints.launchpad.net/ceilometer/+spec/api-group-by
• group by blueprint discussion on the OpenStack wiki: https://wiki.openstack.org/wiki/Ceilometer/blueprints/api-group-by

MongoDB group by Patch Set 5 code review

Patch Set 5 link: https://review.openstack.org/#/c/43043/5/

jd gave me a +2 review, but also had a suggestion on my code, in particular the code block:

PARAMS_MAP_STATS_GROUPBY = {'key_val': 'groupby_key',
                            'groupby_val': 'new Object(groupby)',
                            'period_start_val': 'this.timestamp',
                            'period_end_val': 'this.timestamp'}

in class Connection of ceilometer/storage/impl_mongodb.py

Isn't groupby sufficient? It seems to me that new Object(groupby) == groupby

jd is right; I don't need to create a new object because I only use the variable groupby once. So I replaced new Object(groupby) with simply groupby.

I also made the same replacement in the map function PARAMS_MAP_STATS_PERIOD_GROUPBY.

MongoDB group by Patch Set 6 submitted

After addressing jd's code review on Patch Set 5, I uploaded these changes as Patch Set 6:

https://review.openstack.org/#/c/43043/6/

Blueprint/wiki documentation

I updated the blueprint and wiki to include a section on "MongoDB driver group by implementation". The section includes an explanation of why I chose to stick with the mapReduce() method out of the three MongoDB API aggregation methods (aggregate, mapReduce, group) and some comments about how I designed the map functions.

Map reduce MongoDB references

MongoDB manual

• http://docs.mongodb.org/manual/core/map-reduce/

• http://docs.mongodb.org/manual/reference/command/mapReduce/#dbcmd.mapReduce

• http://docs.mongodb.org/manual/tutorial/map-reduce-examples/

Pymongo documentation

• http://api.mongodb.org/python/current/api/pymongo/collection.html?highlight=map%20reduce#pymongo.collection.Collection.map_reduce

• http://api.mongodb.org/python/current/examples/aggregation.html?highlight=map%20reduce#map-reduce

Other references

• http://blog.pythonisito.com/2012/05/aggregation-in-mongodb-part-1.html

• http://bsonspec.org/

• http://cookbook.mongodb.org/