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  • Committer: Package Import Robot
  • Author(s): Piotr Ożarowski, Jakub Wilk, Piotr Ożarowski
  • Date: 2013-07-06 20:53:52 UTC
  • mfrom: (1.4.23) (16.1.17 experimental)
  • Revision ID: package-import@ubuntu.com-20130706205352-ryppl1eto3illd79
Tags: 0.8.2-1
[ Jakub Wilk ]
* Use canonical URIs for Vcs-* fields.

[ Piotr Ożarowski ]
* New upstream release
* Upload to unstable
* Build depend on python3-all instead of -dev, extensions are not built for
  Python 3.X 

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examples/beaker_caching/helloworld.py
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"""helloworld.py
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Illustrate how to load some data, and cache the results.
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"""
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from environment import Session
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from model import Person
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from caching_query import FromCache
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# load Person objects.  cache the result under the namespace "all_people".
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print "loading people...."
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people = Session.query(Person).options(FromCache("default", "all_people")).all()
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# remove the Session.  next query starts from scratch.
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Session.remove()
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# load again, using the same FromCache option. now they're cached
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# under "all_people", no SQL is emitted.
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print "loading people....again!"
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people = Session.query(Person).options(FromCache("default", "all_people")).all()
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# want to load on some different kind of query ?  change the namespace
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# you send to FromCache
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print "loading people two through twelve"
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people_two_through_twelve = Session.query(Person).\
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                            options(FromCache("default", "people_on_range")).\
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                            filter(Person.name.between("person 02", "person 12")).\
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                            all()
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# the data is cached under the "namespace" you send to FromCache, *plus*
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# the bind parameters of the query.    So this query, having
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# different literal parameters under "Person.name.between()" than the
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# previous one, issues new SQL...
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print "loading people five through fifteen"
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people_five_through_fifteen = Session.query(Person).\
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                            options(FromCache("default", "people_on_range")).\
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                            filter(Person.name.between("person 05", "person 15")).\
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                            all()
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# ... but using the same params as are already cached, no SQL
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print "loading people two through twelve...again!"
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people_two_through_twelve = Session.query(Person).\
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                            options(FromCache("default", "people_on_range")).\
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                            filter(Person.name.between("person 02", "person 12")).\
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                            all()
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# invalidate the cache for the three queries we've done.  Recreate
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# each Query, which includes at the very least the same FromCache,
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# same list of objects to be loaded, and the same parameters in the
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# same order, then call invalidate().
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print "invalidating everything"
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Session.query(Person).options(FromCache("default", "all_people")).invalidate()
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Session.query(Person).\
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            options(FromCache("default", "people_on_range")).\
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            filter(Person.name.between("person 02", "person 12")).invalidate()
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Session.query(Person).\
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            options(FromCache("default", "people_on_range")).\
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            filter(Person.name.between("person 05", "person 15")).invalidate()
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