def generateDesignCandidates(self, collections, isShardingEnabled=True, isIndexesEnabled=True, isDenormalizationEnabled=True):
dc = DesignCandidates()
valid_collection = set()
for col_info in collections.itervalues():
shardKeys = []
indexKeys = []
denorm = []
interesting = col_info['interesting']
valid_collection.add(col_info['name'])
interesting = self.__remove_heuristicaly_bad_key__(col_info, interesting)
# Make sure that none of our interesting fields start with
# the character that we used to convert $ commands
for key in interesting:
assert not key.startswith(constants.REPLACE_KEY_DOLLAR_PREFIX), \
"Unexpected candidate key '%s.%s'" % (col_info["name"], key)
if constants.SKIP_MONGODB_ID_FIELD and "_id" in interesting:
interesting = interesting[:]
interesting.remove("_id")
# deal with shards
if isShardingEnabled:
LOG.debug("Sharding is enabled")
shardKeys = interesting
# deal with indexes
if isIndexesEnabled:
LOG.debug("Indexes is enabled")
for o in xrange(1, len(interesting) + 1) :
if o > constants.MAX_INDEX_SIZE: break
for i in itertools.permutations(interesting, o):
indexKeys.append(i)
## FOR
## FOR
# deal with de-normalization
if len(indexKeys) > 10:
LOG.warn("Too many index keys: %s", len(indexKeys))
if isDenormalizationEnabled:
LOG.debug("Denormalization is enabled")
for k,v in col_info['fields'].iteritems() :
if v['parent_col'] <> None and v['parent_col'] not in denorm and v['parent_col'] in valid_collection:
denorm.append(v['parent_col'])
dc.addCollection(col_info['name'], indexKeys, shardKeys, denorm)
## FOR
return dc
