python/qpid_dispatch_internal/router/message.py

#
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# to you under the Apache License, Version 2.0 (the
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#   http://www.apache.org/licenses/LICENSE-2.0
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from __future__ import unicode_literals
from __future__ import division
from __future__ import absolute_import
from __future__ import print_function
import json

"""Python class to hold message data"""


class Message(object):
    """
    Holder for message attributes used by python IoAdapter send/receive.

    Interface is like proton.Message, but we don't use proton.Message here because
    creating a proton.Message has side-effects on the proton engine.

    @ivar body: The body of the message, normally a map.
    @ivar to: The to-address for the message.
    @ivar reply_to: The reply-to address for the message.
    @ivar correlation_id: Correlation ID for replying to the message.
    @ivar properties: Application properties.
    """

    _fields = ['address', 'properties', 'body', 'reply_to', 'correlation_id', 'content_type']

    def __init__(self, **kwds):
        """All instance variables can be set as keywords. See L{Message}"""
        for f in self._fields:
            setattr(self, f, kwds.get(f, None))
        for k in kwds:
            getattr(self, k)    # Check for bad attributes

    def __repr__(self):
        return "%s(%s)" % (type(self).__name__,
                           ", ".join("%s=%r" % (f, getattr(self, f)) for f in self._fields))


def simplify(msg):
    m = {}
    for k, v in msg.properties.items():
        m[k] = v
    if msg.body:
        m["body"] = msg.body.decode()
    if msg.content_type:
        m["content_type"] = msg.content_type
    return m


def messages_to_json(msgs):
    return json.dumps([simplify(m) for m in msgs], indent=4)