def __init__(self, aws_access_key_id, aws_secret_access_key, bucket_name):
conn = boto.connect_s3(aws_access_key_id, aws_secret_access_key)
self._bucket = Bucket(conn, bucket_name)
class S3Aspect:
'''A storage for Amazon S3 web service
'''
def __init__(self, aws_access_key_id, aws_secret_access_key, bucket_name):
conn = boto.connect_s3(aws_access_key_id, aws_secret_access_key)
self._bucket = Bucket(conn, bucket_name)
def lastCommit(self):
'''
Get the last committed tid and serial according to S3.
This may not be current
'''
prefix = 'type:index_serial,'
rs = self._bucket.get_all_keys(prefix=prefix, maxkeys=1)
if not rs:
# umm not created yet
return None, None
else:
info = dict_from_key(rs[0].key)
tid = tid_unrepr(info['tid'])
serial = serial_unrepr(info['serial'])
return tid, serial
def highestOid(self):
'''
Get the highest oid value
'''
prefix = 'type:record,'
rs = self._bucket.get_all_keys(prefix=prefix, maxkeys=1)
if not rs:
# umm not created yet
return None
else:
info = dict_from_key(rs[0].key)
oid = oid_unrepr(info['oid'])
return oid
def getSerialForTid(self, tid):
'''
get the serial for a tid
'''
prefix = 'type:index_tid,tid:%s,' % tid_repr(tid)
rs = self._bucket.get_all_keys(prefix=prefix, maxkeys=1)
if not rs:
#either it hasn't propogated yet or has been packed away
return None
info = dict_from_key(rs[0].key)
serial = serial_unrepr(info['serial'])
return serial
def loadPickle(self, oid, tid):
"""Actually get the data from s3"""
k = Key(self._bucket)
k.key = 'type:record,oid:%s,tid:%s' % (oid_repr(oid), tid_repr(tid))
if DEBUG: print 'LOAD %s' % k.key
for n in xrange(RETRIES):
try:
return k.get_contents_as_string()
except S3ResponseError:
if DEBUG: print 'RETRY %s' % n
time.sleep(SLEEPTIME)
return k.get_contents_as_string()
def storePickle(self, oid, tid, prev_tid, data):
'''Save the data to s3'''
k = Key(self._bucket)
k.key = 'type:record,oid:%s,tid:%s' % (oid_repr(oid), tid_repr(tid))
if DEBUG: print 'STORE %s' % k.key
for n in xrange(RETRIES):
try:
return k.set_contents_from_string(data)
except:
if DEBUG: print 'RETRY %s' % n
time.sleep(SLEEPTIME)
return k.set_contents_from_string(data)
def findLastCommit(self, oid, serial):
'''
Look for the last committed record for oid committed on or before serial
'''
oid_key = oid_repr(oid)
serial_key = serial_repr(serial)
prefix = 'type:index_oid,oid:%s,' % oid_key
marker = 'type:index_oid,oid:%s,serial:%s,' % (oid_key, serial_key)
rs = self._bucket.get_all_keys(prefix=prefix, marker=marker, maxkeys=1)
if not rs:
return None # no commits yet
key = rs[0]
return dict_from_key(key.key)
def getTrailingTransactions(self, serial):
'''Get commits after serial'''
#
# Lots of reads here. slow!
#
prefix = 'type:transaction,'
# use a / as it is later than a ,
marker = 'type:transaction,order:%s/' % order_repr(serial)
rs = self._bucket.get_all_keys(prefix=prefix, marker=marker)
data = []
for key in rs:
info = dict_from_key(key.key)
packed = key.get_contents_as_string()
assert len(packed) % 8 == 0 # 8 byte packed oids
oids = set(packed[n:n+8] for n in xrange(0, len(packed), 8))
assert len(oids) == len(packed) / 8
data.append((info, oids))
return data
def writeTransaction(self, tid, serial, oids, ude):
packed = ''.join(oid for oid in oids)
k = Key(self._bucket)
k.key = 'type:transaction,order:%s,tid:%s' % (order_repr(serial),
tid_repr(tid))
if DEBUG: print 'COMMIT %s' %k.key
k.set_contents_from_string(packed)
def indexTransaction(self, tid, serial, oids):
for oid in oids:
k = Key(self._bucket)
k.key = 'type:index_oid,oid:%s,serial:%s,tid:%s' %(
oid_repr(oid),
serial_repr(serial),
tid_repr(tid))
k.set_contents_from_string('')
k = Key(self._bucket)
# Index tid to serial
k.key = 'type:index_tid,tid:%s,serial:%s' %(
tid_repr(tid),
serial_repr(serial))
k.set_contents_from_string('')
# Index the highest committed serial
k = Key(self._bucket)
k.key = 'type:index_serial,serial:%s,tid:%s' %(
serial_repr(serial),
tid_repr(tid))
k.set_contents_from_string('')
