diff options
Diffstat (limited to 'git/db/py/pack.py')
| -rw-r--r-- | git/db/py/pack.py | 88 |
1 files changed, 44 insertions, 44 deletions
diff --git a/git/db/py/pack.py b/git/db/py/pack.py index 0d4c533a..e107aba2 100644 --- a/git/db/py/pack.py +++ b/git/db/py/pack.py @@ -5,17 +5,17 @@ """Module containing a database to deal with packs""" from git.db import CachingDB from base import ( - PureRootPathDB, - PureObjectDBR - ) + PureRootPathDB, + PureObjectDBR +) from git.util import LazyMixin from git.exc import ( - BadObject, - UnsupportedOperation, - AmbiguousObjectName - ) + BadObject, + UnsupportedOperation, + AmbiguousObjectName +) from git.pack import PackEntity @@ -28,16 +28,17 @@ __all__ = ('PurePackedODB', ) class PurePackedODB(PureRootPathDB, PureObjectDBR, CachingDB, LazyMixin): + """A database operating on a set of object packs""" - + # the type to use when instantiating a pack entity PackEntityCls = PackEntity - + # sort the priority list every N queries - # Higher values are better, performance tests don't show this has + # Higher values are better, performance tests don't show this has # any effect, but it should have one _sort_interval = 500 - + def __init__(self, root_path): super(PurePackedODB, self).__init__(root_path) # list of lists with three items: @@ -47,16 +48,16 @@ class PurePackedODB(PureRootPathDB, PureObjectDBR, CachingDB, LazyMixin): # self._entities = list() # lazy loaded list self._hit_count = 0 # amount of hits self._st_mtime = 0 # last modification data of our root path - + def _set_cache_(self, attr): if attr == '_entities': self._entities = list() self.update_cache(force=True) # END handle entities initialization - + def _sort_entities(self): self._entities.sort(key=lambda l: l[0], reverse=True) - + def _pack_info(self, sha): """:return: tuple(entity, index) for an item at the given sha :param sha: 20 or 40 byte sha @@ -69,7 +70,7 @@ class PurePackedODB(PureRootPathDB, PureObjectDBR, CachingDB, LazyMixin): if self._hit_count % self._sort_interval == 0: self._sort_entities() # END update sorting - + for item in self._entities: index = item[2](sha) if index is not None: @@ -78,14 +79,14 @@ class PurePackedODB(PureRootPathDB, PureObjectDBR, CachingDB, LazyMixin): return (item[1], index) # END index found in pack # END for each item - + # no hit, see whether we have to update packs # NOTE: considering packs don't change very often, we safe this call # and leave it to the super-caller to trigger that raise BadObject(sha) - - #{ Object DB Read - + + #{ Object DB Read + def has_object(self, sha): try: self._pack_info(sha) @@ -93,15 +94,15 @@ class PurePackedODB(PureRootPathDB, PureObjectDBR, CachingDB, LazyMixin): except BadObject: return False # END exception handling - + def info(self, sha): entity, index = self._pack_info(sha) return entity.info_at_index(index) - + def stream(self, sha): entity, index = self._pack_info(sha) return entity.stream_at_index(index) - + def sha_iter(self): sha_list = list() for entity in self.entities(): @@ -111,35 +112,34 @@ class PurePackedODB(PureRootPathDB, PureObjectDBR, CachingDB, LazyMixin): yield sha_by_index(index) # END for each index # END for each entity - + def size(self): sizes = [item[1].index().size() for item in self._entities] - return reduce(lambda x,y: x+y, sizes, 0) - + return reduce(lambda x, y: x + y, sizes, 0) + #} END object db read - + #{ object db write - + def store(self, istream): """Storing individual objects is not feasible as a pack is designed to hold multiple objects. Writing or rewriting packs for single objects is inefficient""" raise UnsupportedOperation() - + def store_async(self, reader): # TODO: add PureObjectDBRW before implementing this raise NotImplementedError() - + #} END object db write - - - #{ Interface - + + #{ Interface + def update_cache(self, force=False): """ Update our cache with the acutally existing packs on disk. Add new ones, and remove deleted ones. We keep the unchanged ones - + :param force: If True, the cache will be updated even though the directory does not appear to have changed according to its modification timestamp. :return: True if the packs have been updated so there is new information, @@ -149,12 +149,12 @@ class PurePackedODB(PureRootPathDB, PureObjectDBR, CachingDB, LazyMixin): return False # END abort early on no change self._st_mtime = stat.st_mtime - + # packs are supposed to be prefixed with pack- by git-convention # get all pack files, figure out what changed pack_files = set(glob.glob(os.path.join(self.root_path(), "pack-*.pack"))) our_pack_files = set(item[1].pack().path() for item in self._entities) - + # new packs for pack_file in (pack_files - our_pack_files): # init the hit-counter/priority with the size, a good measure for hit- @@ -162,7 +162,7 @@ class PurePackedODB(PureRootPathDB, PureObjectDBR, CachingDB, LazyMixin): entity = self.PackEntityCls(pack_file) self._entities.append([entity.pack().size(), entity, entity.index().sha_to_index]) # END for each new packfile - + # removed packs for pack_file in (our_pack_files - pack_files): del_index = -1 @@ -175,15 +175,15 @@ class PurePackedODB(PureRootPathDB, PureObjectDBR, CachingDB, LazyMixin): assert del_index != -1 del(self._entities[del_index]) # END for each removed pack - + # reinitialize prioritiess self._sort_entities() return True - + def entities(self): """:return: list of pack entities operated upon by this database""" - return [ item[1] for item in self._entities ] - + return [item[1] for item in self._entities] + def partial_to_complete_sha(self, partial_binsha, canonical_length): """:return: 20 byte sha as inferred by the given partial binary sha :param partial_binsha: binary sha with less than 20 bytes @@ -202,11 +202,11 @@ class PurePackedODB(PureRootPathDB, PureObjectDBR, CachingDB, LazyMixin): candidate = sha # END handle full sha could be found # END for each entity - + if candidate: return candidate - + # still not found ? raise BadObject(partial_binsha) - + #} END interface |