def searchIndices(indices, query, period, lastId=None, reverse=False, fields=None, limit=100):
"""
Search the specified indices for events matching the specified query.
:param indices: A list of indices to search.
:type indices: A list of objects implementing :class:`terane.bier.index.IIndex`
:param query: The programmatic query to use for searching the indices.
:type query: An object implementing :class:`terane.bier.searching.IQuery`
:param period: The period within which the search is constrained.
:type period: :class:`terane.bier.searching.Period`
:param lastId: The real key to start iterating from.
:type lastId: :class:`terane.bier.evid.EVID`
:param reverse: If True, then reverse the order of events.
:type reverse: bool
:param fields: If not None, then only return the specified fields of each event.
:type fields: list or None
:param limit: Only returned the specified number of events.
:type limit: int
:returns: A CooperativeTask which contains a Deferred and manages the search task.
:rtype: :class:`twisted.internet.task.CooperativeTask`
"""
start = time.time()
# determine the evids to use as start and end keys
if reverse == False:
startId, endId = period.getRange()
else:
endId, startId = period.getRange()
if lastId != None:
if not lastId in period:
raise SearcherError("lastId %s is not within period" % lastId)
startId = lastId
# search each index separately, then merge the results
try:
searchers = []
postingLists = []
for index in indices:
if not IIndex.providedBy(index):
raise TypeError("index does not implement IIndex")
# we create a copy of the original query, which can possibly be optimized
# with index-specific knowledge.
_query = copy.deepcopy(query)
try:
_query = _query.optimizeMatcher(index)
except NotImplementedError, e:
raise SearcherError(str(e))
logger.debug("optimized query for index '%s': %s" % (index.name, str(_query)))
# if the query optimized out entirely, then skip to the next index
if _query == None:
continue
# get the posting list to iterate through
searcher = index.newSearcher()
if not ISearcher.providedBy(searcher):
raise TypeError("searcher does not implement ISearcher")
postingList = _query.iterMatches(searcher, startId, endId)
if not IPostingList.providedBy(postingList):
raise TypeError("posting list does not implement IPostingList")
searchers.append(searcher)
postingLists.append(postingList)
# return a cooperative task
return cooperate(ResultSet(searchers, postingLists, start, reverse, fields, limit))
def next(self):
start = time.time()
searchers = []
postingLists = []
try:
# get a searcher and posting list for each index
for index in self._indices:
# we create a copy of the original query, which can possibly be optimized
# with index-specific knowledge.
query = copy.deepcopy(self._query)
# get the posting list to iterate through
searcher = yield index.newSearcher()
if not ISearcher.providedBy(searcher):
raise TypeError("searcher does not implement ISearcher")
query = yield query.optimizeMatcher(searcher)
logger.debug("optimized query for index '%s': %s" % (index.name,str(query)))
# if the query optimized out entirely, then skip to the next index
if query == None:
yield searcher.close()
continue
postingList = yield query.iterMatches(searcher, self._startId, self._endId)
if not IPostingList.providedBy(postingList):
raise TypeError("posting list does not implement IPostingList")
searchers.append(searcher)
postingLists.append(postingList)
if len(postingLists) == 0:
raise StopIteration()
# loop forever until we reach the search limit, we exhaust all of our
# posting lists, or we encounter an exception
currPostings = [(None,None,None) for i in range(len(postingLists))]
smallestList = 0
lastId = None
compar = (lambda x,y: cmp(y,x)) if self._reverse else cmp
while True:
# if we have reached our limit
if len(self.events) == self._limit:
self.runtime = time.time() - start
raise StopIteration()
# check each child iter for the lowest evid
for currList in range(len(postingLists)):
if currList == None:
smallestList = 0
# if the postingList is None, then its closed
if postingLists[currList] == None:
# FIXME: close the posting list and searcher
continue
# if current posting for this posting list was not consumed
if currPostings[currList] != (None,None,None):
continue
# otherwise get the next posting from the posting list
currPostings[currList] = yield postingLists[currList].nextPosting()
# if the next posting for this posting list is (None,None,None),
# then we are done with this posting list
if currPostings[currList] == (None,None,None):
postingList = postingLists[currList]
yield postingList.close()
postingLists[currList] = None
continue
# if the evid equals the last evid returned, then ignore it
if lastId != None and currPostings[currList][0] == lastId:
currPostings[currList] = (None,None,None)
continue
# we don't compare the first evid with itself
if currList == 0:
continue
# if the evid is the current smallest evid, then remember it
if (currPostings[smallestList] == (None,None,None) or
compar(currPostings[currList][0], currPostings[smallestList][0]) < 0):
smallestList = currList
# get the next posting
currList = None
evid,_,store = currPostings[smallestList]
# stop iterating if there are no more results
if evid == None:
self.runtime = time.time() - start
raise StopIteration()
# remember the last evid
lastId = evid
# forget the evid so we don't return it again
currPostings[smallestList] = (None,None,None)
# retrieve the event
if not IEventStore.providedBy(store):
raise TypeError("store does not implement IEventStore")
event = yield store.getEvent(evid)
defaultfield, defaultvalue, fields = event
if defaultfield not in self.fields:
self.fields.append(defaultfield)
# keep a record of all field names found in the results
for fieldname in fields.keys():
if fieldname not in self.fields:
self.fields.append(fieldname)
# filter out unwanted fields
if self._fields != None:
fields = dict([(k,v) for k,v in fields.items() if k in self._fields])
self.events.append(((evid.ts,evid.offset), defaultfield, defaultvalue, fields))
logger.trace("added event %s to results" % evid)
finally:
for postingList in postingLists:
if postingList != None:
yield postingList.close()
for searcher in searchers:
yield searcher.close()
def next(self):
start = time.time()
searchers = []
postingLists = []
try:
# get a searcher and posting list for each index
for index in self._indices:
# we create a copy of the original query, which can possibly be optimized
# with index-specific knowledge.
query = copy.deepcopy(self._query)
# get the posting list to iterate through
searcher = yield index.newSearcher()
if not ISearcher.providedBy(searcher):
raise TypeError("searcher does not implement ISearcher")
query = yield query.optimizeMatcher(searcher)
logger.debug("optimized query for index '%s': %s" %
(index.name, str(query)))
# if the query optimized out entirely, then skip to the next index
if query == None:
yield searcher.close()
continue
postingList = yield query.iterMatches(searcher, self._startId,
self._endId)
if not IPostingList.providedBy(postingList):
raise TypeError(
"posting list does not implement IPostingList")
searchers.append(searcher)
postingLists.append(postingList)
if len(postingLists) == 0:
raise StopIteration()
# loop forever until we reach the search limit, we exhaust all of our
# posting lists, or we encounter an exception
currPostings = [(None, None, None)
for i in range(len(postingLists))]
smallestList = 0
lastId = None
compar = (lambda x, y: cmp(y, x)) if self._reverse else cmp
while True:
# if we have reached our limit
if len(self.events) == self._limit:
self.runtime = time.time() - start
raise StopIteration()
# check each child iter for the lowest evid
for currList in range(len(postingLists)):
if currList == None:
smallestList = 0
# if the postingList is None, then its closed
if postingLists[currList] == None:
# FIXME: close the posting list and searcher
continue
# if current posting for this posting list was not consumed
if currPostings[currList] != (None, None, None):
continue
# otherwise get the next posting from the posting list
currPostings[currList] = yield postingLists[
currList].nextPosting()
# if the next posting for this posting list is (None,None,None),
# then we are done with this posting list
if currPostings[currList] == (None, None, None):
postingList = postingLists[currList]
yield postingList.close()
postingLists[currList] = None
continue
# if the evid equals the last evid returned, then ignore it
if lastId != None and currPostings[currList][0] == lastId:
currPostings[currList] = (None, None, None)
continue
# we don't compare the first evid with itself
if currList == 0:
continue
# if the evid is the current smallest evid, then remember it
if (currPostings[smallestList] == (None, None, None)
or compar(currPostings[currList][0],
currPostings[smallestList][0]) < 0):
smallestList = currList
# get the next posting
currList = None
evid, _, store = currPostings[smallestList]
# stop iterating if there are no more results
if evid == None:
self.runtime = time.time() - start
raise StopIteration()
# remember the last evid
lastId = evid
# forget the evid so we don't return it again
currPostings[smallestList] = (None, None, None)
# retrieve the event
if not IEventStore.providedBy(store):
raise TypeError("store does not implement IEventStore")
event = yield store.getEvent(evid)
defaultfield, defaultvalue, fields = event
if defaultfield not in self.fields:
self.fields.append(defaultfield)
# keep a record of all field names found in the results
for fieldname in fields.keys():
if fieldname not in self.fields:
self.fields.append(fieldname)
# filter out unwanted fields
if self._fields != None:
fields = dict([(k, v) for k, v in fields.items()
if k in self._fields])
self.events.append(((evid.ts, evid.offset), defaultfield,
defaultvalue, fields))
logger.trace("added event %s to results" % evid)
finally:
for postingList in postingLists:
if postingList != None:
yield postingList.close()
for searcher in searchers:
yield searcher.close()
