class AvroSerializer(Serializer):
def __init__(
self,
schema_registry_url: str,
auto_register_schemas: bool = True,
subject_name_strategy: SubjectNameStrategy = SubjectNameStrategy.
RecordNameStrategy,
**kwargs):
super().__init__(**kwargs)
schema_registry_url = schema_registry_url
self.schema_registry = CachedSchemaRegistryClient(schema_registry_url)
self.auto_register_schemas = auto_register_schemas
self.subject_name_strategy = subject_name_strategy
self._serializer_impl = AvroSerDeBase(self.schema_registry)
def _get_subject(self, topic: str, schema, is_key=False):
if self.subject_name_strategy == SubjectNameStrategy.TopicNameStrategy:
subject = topic + ('-key' if is_key else '-value')
elif self.subject_name_strategy == SubjectNameStrategy.RecordNameStrategy:
subject = schema.fullname
elif self.subject_name_strategy == SubjectNameStrategy.TopicRecordNameStrategy:
subject = '{}-{}'.format(topic, schema.fullname)
else:
raise ValueError('Unknown SubjectNameStrategy')
return subject
def _ensure_schema(self, topic: str, schema, is_key=False):
subject = self._get_subject(topic, schema, is_key)
if self.auto_register_schemas:
schema_id = self.schema_registry.register(subject, schema)
schema = self.schema_registry.get_by_id(schema_id)
else:
schema_id, schema, _ = self.schema_registry.get_latest_schema(
subject)
return schema_id, schema
def serialize(self, value: AvroRecord, topic: str, is_key=False, **kwargs):
schema_id, _ = self._ensure_schema(topic, value.schema, is_key)
return self._serializer_impl.encode_record_with_schema_id(
schema_id, value, is_key)
class AvroSerializerBase(Serializer):
def __init__(
self,
schema_registry_url: str,
auto_register_schemas: bool = True,
subject_name_strategy: SubjectNameStrategy = SubjectNameStrategy.RecordNameStrategy,
**kwargs,
):
super().__init__(**kwargs)
schema_registry_url = schema_registry_url
self.schema_registry = CachedSchemaRegistryClient(schema_registry_url)
self.auto_register_schemas = auto_register_schemas
self.subject_name_strategy = subject_name_strategy
self._serializer_impl = AvroSerDeBase(self.schema_registry)
def _get_subject(self, topic: str, schema, is_key=False):
if self.subject_name_strategy == SubjectNameStrategy.TopicNameStrategy:
subject = topic + ("-key" if is_key else "-value")
elif self.subject_name_strategy == SubjectNameStrategy.RecordNameStrategy:
subject = schema.fullname
elif self.subject_name_strategy == SubjectNameStrategy.TopicRecordNameStrategy:
subject = "{}-{}".format(topic, schema.fullname)
else:
raise ValueError("Unknown SubjectNameStrategy")
return subject
def _ensure_schema(self, topic: str, schema, is_key=False):
subject = self._get_subject(topic, schema, is_key)
if self.auto_register_schemas:
schema_id = self.schema_registry.register(subject, schema)
schema = self.schema_registry.get_by_id(schema_id)
else:
schema_id, schema, _ = self.schema_registry.get_latest_schema(subject)
return schema_id, schema
@abc.abstractmethod
def serialize(self, value, topic, **kwargs):
raise NotImplementedError
