sdk-python/cloudevents/sdk/converters/structured.py

61 lines
2.0 KiB
Python

# All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
import typing
from cloudevents.sdk import types
from cloudevents.sdk.converters import base
from cloudevents.sdk.converters.util import has_binary_headers
from cloudevents.sdk.event import base as event_base
# TODO: Singleton?
class JSONHTTPCloudEventConverter(base.Converter):
TYPE = "structured"
MIME_TYPE = "application/cloudevents+json"
def can_read(
self, content_type: str, headers: typing.Dict[str, str] = {}
) -> bool:
return (
isinstance(content_type, str)
and content_type.startswith(self.MIME_TYPE)
or not has_binary_headers(headers)
)
def event_supported(self, event: object) -> bool:
# structured format supported by both spec 0.1 and 0.2
return True
def read(
self,
event: event_base.BaseEvent,
headers: dict,
body: typing.IO,
data_unmarshaller: types.UnmarshallerType,
) -> event_base.BaseEvent:
event.UnmarshalJSON(body, data_unmarshaller)
return event
def write(
self, event: event_base.BaseEvent, data_marshaller: types.MarshallerType
) -> typing.Tuple[dict, bytes]:
http_headers = {"content-type": self.MIME_TYPE}
return http_headers, event.MarshalJSON(data_marshaller).encode("utf-8")
def NewJSONHTTPCloudEventConverter() -> JSONHTTPCloudEventConverter:
return JSONHTTPCloudEventConverter()