support amqp10 message without body

[thorhalvor]

Proposed Changes

Currently RabbitMQ-server does not support an AMQP 1.0 message with empty/undefined body.
My understanding of the AMQP 1.0 protocol is that this is perfectly valid case.
Many systems sends a message with properties only. They could set an empty array as Body, but that need changes in sometimes hundreds of client-applications.

This change will accept if Body is 'undefined'.

I used AmqpNetLite library and published a message where BodySection is not set

    var message = new Message
    {
        // BodySection = <notset>
        Properties = new Properties()
    };

and the error occured.

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[kjnilsson]

@thorhalvor please can you refer to the section of the spec where you got this interpretation? I am not sure it is correct if you look at §3.2 it reads as if only the body is required.

Altogether a message consistsof the following sections:
• Zero or one header.
• Zero or one delivery-annotations.
• Zero or one message-annotations.
• Zero or one properties.
• Zero or one application-properties.
• The body consists of one of the following three choices: one or more data sections, one or more amqp-sequence
sections, or a single amqp-value section.
• Zero or one footer.