def createOrUpdate(wave_id, wavelet_id, participant_profiles=None):
'''
Creates or updates a followed wave and wave meta object
@param wave_id: the id of the wave these records are for
@param wavelet_id: the id of the wavelet these records are for
@param participant_profiles=None: the participant profiles for this wave
'''
#Fetch or create
waveMeta = get(wave_id, wavelet_id)
if not waveMeta:
followedWave = FollowedWave(wave_id = wave_id,
wavelet_id = wavelet_id,
key_name = _generateFollowedWaveKey( wave_id,
wavelet_id))
_putFollowedWave(followedWave)
waveMeta = WaveMeta(parent = followedWave)
if participant_profiles:
waveMeta.participant_profiles = participant_profiles
put(waveMeta, wave_id, wavelet_id)
def _getWaveMeta(followedWave):
'''
Returns a wave meta instance if it can be found in the datastore or
memcache
@transaction_safe
@param followedWave: the parent followedWave instance
@return the WaveMeta instance or None if it was not found
'''
key = base64.b64encode( memcacheConfig.PREFIX['WAVE_META'] +
followedWave.wave_id +
followedWave.wavelet_id)
waveMeta = memcache.get(key)
if not waveMeta == None:
return waveMeta
else:
query = WaveMeta.all()
query.ancestor(followedWave)
waveMeta = query.get()
memcache.add(key, waveMeta, time=memcacheConfig.DEFAULT_EXPIRE_SECS)
return waveMeta
