Merge lp:~jtv/launchpad/getBinariesForDomination-bulk into lp:launchpad

[Jeroen T. Vermeulen]

Bulk-fetch BinaryPackageReleases in Dominator before sorting.

This is a little side-note to some Dominator optimization work I'm doing for bug 884649: bulk-fetch BinaryPackageReleases when querying for BinaryPackagePublishingHistory records.

There is no functional change, so existing tests apply unchanged.

As far as I can tell, the only performance downside to this is that the query returns more data; nothing else about the query changes, and there should be very little duplication between the extra objects (any duplication only happens, as far as I can see, when a package moves from one component to another or something relatively rare along those lines).

Existing tests:
{{{
./bin/test -vvc lp.archivepublisher.tests.test_dominator
}}}

No lint.

Jeroen

[Raphaël Badin (rvb)]

Looks good.

(Maybe you could use the denormalized attribute on BinaryPackagePublishingHistory to get the relative BinaryPackageNames.)

review: Approve

[Jeroen T. Vermeulen (jtv)]

Not sure what attribute that is. It's not a matter of getting at the BPNs though, but of bulk-loading them.

[Raphaël Badin (rvb)]

> Not sure what attribute that is. It's not a matter of getting at the BPNs
> though, but of bulk-loading them.

As discussed on IRC, I was talking about the denormalized attribute BPPH.binarypackagename that stevenK has added recently. It is populated now.

=== modified file 'lib/lp/archivepublisher/domination.py'
--- lib/lp/archivepublisher/domination.py	2011-11-02 13:36:51 +0000
+++ lib/lp/archivepublisher/domination.py	2011-11-02 13:36:53 +0000
@@ -491,7 +491,16 @@
         main_clauses.extend(bpph_location_clauses)
 
         store = IStore(BinaryPackagePublishingHistory)
-        return store.find(BinaryPackagePublishingHistory, *main_clauses)
+
+        # We're going to access the BPRs as well.  Since we make the
+        # database look them up anyway, and since there won't be many
+        # duplications among them, load them alongside the publications.
+        # We'll also want their BinaryPackageNames, but adding those to
+        # the join would complicate the query.
+        query = store.find(
+            (BinaryPackagePublishingHistory, BinaryPackageRelease),
+            *main_clauses)
+        return DecoratedResultSet(query, itemgetter(0))
 
     def dominateBinaries(self, distroseries, pocket):
         """Perform domination on binary package publications.