def denorm_instance(payload):
logging.info('[map_reduce.denorm_instance] payload %s' % json.dumps(payload))
source_model = util.get_model_by_name(payload['source_model'])
target_model = util.get_model_by_name(payload['target_model'])
related_field_name = payload['related_field']
fields = payload['fields']
storage = payload['storage']
if storage == 'scalar':
related_field_name_filter = related_field_name+'_id'
denorm_values = fields
else:
assert(storage == 'shared_dict')
# will look up source primary key in target's list field
related_field_name_filter = Inflector().pluralize(related_field_name)
denorm_values = {
'denorm_data': {
related_field_name_filter: {
payload['instance_id']: fields
}
}
}
pipeline = MapperPipeline(
'denorm-target-%s-source-%s-instance-%s-at-%s' % (payload['target_model'], payload['source_model'], payload['instance_id'], now().isoformat()),
handler_spec = util.convert_func_to_string(denorm_entity_mapper),
input_reader_spec = 'djangoappengine.mapreduce.input_readers.DjangoModelInputReader', # FIXME: should be self-contained
output_writer_spec = util.convert_func_to_string(NullOutputWriter),
params = {
# _convert_model_to_string is a different encoding than util.get_model_name, but we have to use because
# we use djangoappengine's input reader
'entity_kind': _convert_model_to_string(target_model),
'queue_name': payload['queue_name'],
'filters': [
[related_field_name_filter, '=', payload['instance_id']],
],
'denorm_values': denorm_values,
#'storage': storage,
},
shards = payload['shards']
)
pipeline.start(queue_name=payload['queue_name'])
pipeline_id = pipeline.pipeline_id
logging.info('[map_reduce.denorm_instance] pipeline_id = %s' % str(pipeline_id))
def register(target_model, options):
logging.info('[denorm.register] %s' % target_model)
if not hasattr(target_model, '_meta'):
raise AttributeError('The model being registered must derive from Model.')
target = util.get_model_name(target_model)
target_options = target_model._meta
# register signals for target. use dispatch_uid to prevent duplicates.
# about signals: https://docs.djangoproject.com/en/1.8/topics/signals/
# built-in signals: https://docs.djangoproject.com/en/1.8/ref/signals/
db_signals.post_init.connect(receivers.target_model_post_init, sender=target_model, dispatch_uid='denorm_target_%s_post_init'%target)
db_signals.pre_save.connect(receivers.target_model_pre_save, sender=target_model, dispatch_uid='denorm_target_%s_pre_save'%target)
db_signals.post_save.connect(receivers.target_model_post_save, sender=target_model, dispatch_uid='denorm_target_%s_post_save'%target)
target_graph = core.TARGET_GRAPH[target_model] = core.TARGET_GRAPH.get(target_model, {})
for source, source_dict in options['sources'].iteritems():
strategy = source_dict.get('strategy', 'cursor') # options are: [cursor, mapreduce]. defaults to cursor.
# TODO: support storage options 'list' and 'dict'
storage = source_dict.get('storage', 'scalar') # choices: [scalar, shared_dict]
if storage == 'scalar':
target_foreign_key = target_options.get_field(source)
# if field did not exist, then get_field would have raised FieldDoesNotExist
if not isinstance(target_foreign_key, ForeignKey):
raise AttributeError('The source field %s.%s must be a ForeignKey' % (target, source))
source_model = target_foreign_key.rel.to
elif storage == 'shared_dict':
target_foreign_key_list = target_options.get_field(Inflector().pluralize(source))
# if field did not exist, then get_field would have raised FieldDoesNotExist
if not isinstance(target_foreign_key_list, tb_fields.ListField):
raise AttributeError('The target field %s.%s must be a ListField' % (target, source))
# model must be explicitly configured, because target field does not specify it
source_model = source_dict.get('model')
# create denorm data field
try:
target_options.get_field('denorm_data')
except FieldDoesNotExist:
# field should not exist. now let's create it.
denorm_data_field = JSONField(name='denorm_data', null=True, blank=True,
decoder_kwargs={'cls': json_fields.JSONDecoder, 'parse_float':float})
denorm_data_field.contribute_to_class(target_model, 'denorm_data')
else:
# field was already created on prior source field
# TODO: do at beginning of target model configuration to make sure developer did not define it
pass
else:
logging.error('[denorm.register] invalid storage option %s' % storage)
source_options = source_model._meta
# register signals for source. use dispatch_uid to prevent duplicates.
db_signals.post_init.connect(receivers.source_model_post_init, sender=source_model, dispatch_uid='denorm_source_%s_post_init'%source)
db_signals.pre_save.connect(receivers.source_model_pre_save, sender=source_model, dispatch_uid='denorm_source_%s_pre_save'%source)
db_signals.post_save.connect(receivers.source_model_post_save, sender=source_model, dispatch_uid='denorm_source_%s_post_save'%source)
# FIXME: it's quirky that label and throttles must be configured under each target-source in app's denorm_fields,
# FIXME: but it gets applied here for entire source (not target dependent). it probably should be configured once
# FIXME: per source, but how do accomplish that in the current configuration design?
source_graph = core.SOURCE_GRAPH[source_model] = core.SOURCE_GRAPH.get(source_model, {
'label': source_dict.get('label'),
'throttles': source_dict.get('throttles'),
'fields': {}
})
source_graph_fields = source_graph['fields']
# mark model as registered for denormalization
source_model._denorm_registered = True
# clone list, so that if we add _id below, it doesn't corrupt original list
denorm_field_names = list(source_dict['fields'])
target_graph[source] = {
'fields': denorm_field_names,
'storage': storage,
'source_model': source_model # important for shared_dict storage, because we don't know source model based on list field
}
for i, denorm_field_name in enumerate(denorm_field_names):
source_field = source_options.get_field(denorm_field_name)
# if field did not exist, then get_field would have raised FieldDoesNotExist
target_field_name = '%s_%s' % (source, denorm_field_name)
if storage == 'scalar':
try:
target_options.get_field(target_field_name)
except FieldDoesNotExist:
# field should not exist, so we're good
pass
else:
raise AttributeError('The denorm field %s.%s must not already exist' % (target_model.__name__, target_field_name))
# create target field of same type as source_field
target_field = _copy_field(source_field, target_field_name, target)
target_field.contribute_to_class(target_model, target_field_name)
#print('added field %s with name %s, column %s' % (target_field, target_field_name, target_field.column))
#print('added field %s with name %s' % (target_model._meta.get_field(target_field_name), target_field_name))
else:
assert(storage == 'shared_dict')
# denorm_data field was already created outside this iteration loop
pass
# if source field is a foreign key, then we reference its key rather than the actual related field,
# because we are not deferencing further than the key, and do not want to do an extra db lookup.
if isinstance(source_field, ForeignKey):
denorm_field_name += '_id'
denorm_field_names[i] = denorm_field_name
source_field_graph = source_graph_fields[denorm_field_name] = source_graph_fields.get(denorm_field_name, [])
source_field_graph.append({
'target_model': target_model,
'source': source,
'strategy': strategy,
'storage': storage,
'shards': source_dict.get('shards') and util.convert_func_to_string(source_dict['shards'])
})
def register(target_model, options):
logging.info('[denorm.register] %s' % target_model)
if not hasattr(target_model, '_meta'):
raise AttributeError(
'The model being registered must derive from Model.')
target = util.get_model_name(target_model)
target_options = target_model._meta
# register signals for target. use dispatch_uid to prevent duplicates.
# about signals: https://docs.djangoproject.com/en/1.8/topics/signals/
# built-in signals: https://docs.djangoproject.com/en/1.8/ref/signals/
db_signals.post_init.connect(receivers.target_model_post_init,
sender=target_model,
dispatch_uid='denorm_target_%s_post_init' %
target)
db_signals.pre_save.connect(receivers.target_model_pre_save,
sender=target_model,
dispatch_uid='denorm_target_%s_pre_save' %
target)
db_signals.post_save.connect(receivers.target_model_post_save,
sender=target_model,
dispatch_uid='denorm_target_%s_post_save' %
target)
target_graph = core.TARGET_GRAPH[target_model] = core.TARGET_GRAPH.get(
target_model, {})
for source, source_dict in options['sources'].iteritems():
strategy = source_dict.get(
'strategy',
'cursor') # options are: [cursor, mapreduce]. defaults to cursor.
# TODO: support storage options 'list' and 'dict'
storage = source_dict.get('storage',
'scalar') # choices: [scalar, shared_dict]
if storage == 'scalar':
target_foreign_key = target_options.get_field(source)
# if field did not exist, then get_field would have raised FieldDoesNotExist
if not isinstance(target_foreign_key, ForeignKey):
raise AttributeError(
'The source field %s.%s must be a ForeignKey' %
(target, source))
source_model = target_foreign_key.rel.to
elif storage == 'shared_dict':
target_foreign_key_list = target_options.get_field(
Inflector().pluralize(source))
# if field did not exist, then get_field would have raised FieldDoesNotExist
if not isinstance(target_foreign_key_list, tb_fields.ListField):
raise AttributeError(
'The target field %s.%s must be a ListField' %
(target, source))
# model must be explicitly configured, because target field does not specify it
source_model = source_dict.get('model')
# create denorm data field
try:
target_options.get_field('denorm_data')
except FieldDoesNotExist:
# field should not exist. now let's create it.
denorm_data_field = JSONField(name='denorm_data',
null=True,
blank=True,
decoder_kwargs={
'cls':
json_fields.JSONDecoder,
'parse_float': float
})
denorm_data_field.contribute_to_class(target_model,
'denorm_data')
else:
# field was already created on prior source field
# TODO: do at beginning of target model configuration to make sure developer did not define it
pass
else:
logging.error('[denorm.register] invalid storage option %s' %
storage)
source_options = source_model._meta
# register signals for source. use dispatch_uid to prevent duplicates.
db_signals.post_init.connect(
receivers.source_model_post_init,
sender=source_model,
dispatch_uid='denorm_source_%s_post_init' % source)
db_signals.pre_save.connect(receivers.source_model_pre_save,
sender=source_model,
dispatch_uid='denorm_source_%s_pre_save' %
source)
db_signals.post_save.connect(
receivers.source_model_post_save,
sender=source_model,
dispatch_uid='denorm_source_%s_post_save' % source)
# FIXME: it's quirky that label and throttles must be configured under each target-source in app's denorm_fields,
# FIXME: but it gets applied here for entire source (not target dependent). it probably should be configured once
# FIXME: per source, but how do accomplish that in the current configuration design?
source_graph = core.SOURCE_GRAPH[source_model] = core.SOURCE_GRAPH.get(
source_model, {
'label': source_dict.get('label'),
'throttles': source_dict.get('throttles'),
'fields': {}
})
source_graph_fields = source_graph['fields']
# mark model as registered for denormalization
source_model._denorm_registered = True
# clone list, so that if we add _id below, it doesn't corrupt original list
denorm_field_names = list(source_dict['fields'])
target_graph[source] = {
'fields': denorm_field_names,
'storage': storage,
'source_model':
source_model # important for shared_dict storage, because we don't know source model based on list field
}
for i, denorm_field_name in enumerate(denorm_field_names):
source_field = source_options.get_field(denorm_field_name)
# if field did not exist, then get_field would have raised FieldDoesNotExist
target_field_name = '%s_%s' % (source, denorm_field_name)
if storage == 'scalar':
try:
target_options.get_field(target_field_name)
except FieldDoesNotExist:
# field should not exist, so we're good
pass
else:
raise AttributeError(
'The denorm field %s.%s must not already exist' %
(target_model.__name__, target_field_name))
# create target field of same type as source_field
target_field = _copy_field(source_field, target_field_name,
target)
target_field.contribute_to_class(target_model,
target_field_name)
#print('added field %s with name %s, column %s' % (target_field, target_field_name, target_field.column))
#print('added field %s with name %s' % (target_model._meta.get_field(target_field_name), target_field_name))
else:
assert (storage == 'shared_dict')
# denorm_data field was already created outside this iteration loop
pass
# if source field is a foreign key, then we reference its key rather than the actual related field,
# because we are not deferencing further than the key, and do not want to do an extra db lookup.
if isinstance(source_field, ForeignKey):
denorm_field_name += '_id'
denorm_field_names[i] = denorm_field_name
source_field_graph = source_graph_fields[
denorm_field_name] = source_graph_fields.get(
denorm_field_name, [])
source_field_graph.append({
'target_model':
target_model,
'source':
source,
'strategy':
strategy,
'storage':
storage,
'shards':
source_dict.get('shards')
and util.convert_func_to_string(source_dict['shards'])
})
