[MERGE][#248153] Add autopack RPC

[Martin Pool]

Martin Pool has voted comment.
Status is now: Semi-approved
Comment:
This definitely deserves a mention in NEWS, including some kind of
quantification of what improvement it will give you, and a description 
of
what will happen if the server is too old.

+    def autopack(self):
+        path = self.bzrdir._path_for_remote_call(self._client)
+        try:
+            response = self._client.call('PackRepository.autopack', 
path)
+        except errors.ErrorFromSmartServer, err:
+            self._translate_error(err)
+        except errors.UnknownSmartMethod:
+            self._ensure_real()
+            self._real_repository._pack_collection.autopack()
+            return
+        if self._real_repository is not None:
+            # Reset the real repository's cache of pack names.
+            self._real_repository._pack_collection.reload_pack_names()
+        if response != ('ok',):
+            raise errors.UnexpectedSmartServerResponse(response)
+

While we're here, it seems like an obvious opportunity to have the
PackRepository.autopack command return the pack names data, so that we
don't need to do another roundtrip.  I can see two counterarguments
though, one being that it might not be trivial to inject it into the
_real_repository, and the other that if we can often get away without
vfs-based operations it may be unnecessary.  But at least the second 
does
not seem to be true in the near future.

@@ -1796,4 +1813,11 @@
          raise errors.UnstackableRepositoryFormat(*err.error_args)
      elif err.error_verb == 'NotStacked':
          raise errors.NotStacked(branch=find('branch'))
+    elif err.error_verb == 'NotPackRepository':
+        # There's no specific exception to raise for this, because it 
shouldn't
+        # happen unless something has changed the remote repo's format 
between
+        # smart requests.
+        raise errors.InternalBzrError(
+            'Tried to use PackRepository verb, but remote side says '
+            '%s is not a pack repository.' % (find('repository')))
      raise errors.UnknownErrorFromSmartServer(err)


This seems a bit specific.  Should we just have a generic error for all
rpcs meaning "this operation is not supported on this repository".


For details, see: 
http://bundlebuggy.aaronbentley.com/project/bzr/request/%3C20081029215708.GA3904%40steerpike.home.puzzling.org%3E
Project: Bazaar