Why does AMQP_1 not preserve properties like message-id?

[zhlangsas]

AMQP_1 does not preserve properties such as message-id and correlation-id. And there seems to be no way to set those fields on the output either. I understand that message-id can be non-string type in amqp 1.0, so it doesn't really fit with the metadata in Connect, but this makes tracking messages from JMS systems very difficult.

I'd appreciate some input on best practices in the absence of this capability, or if there are plans for preserving the rest of the ampq 1.0 properties.

[mmatczuk]

You're right — this is a gap in the current implementation. I've opened a PR to address it: #4225

What's new on input:

All standard AMQP 1.0 message properties are now extracted as metadata:

• amqp_message_id
• amqp_correlation_id
• amqp_subject
• amqp_reply_to
• amqp_group_id
• amqp_group_sequence
• amqp_reply_to_group_id
• amqp_user_id
• amqp_absolute_expiry_time

MessageID and CorrelationID are type-aware — UUID values are formatted as xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx, uint64 as decimal strings, and byte arrays as strings.

What's new on output:

Individual interpolated string fields to set each property:

output:
  amqp_1:
    urls: ["amqp://localhost:5672/"]
    target_address: "queue:/destination"
    message_properties_message_id: '${! meta("amqp_message_id") }'
    message_properties_correlation_id: '${! meta("amqp_correlation_id") }'
    message_properties_subject: '${! meta("amqp_subject") }'
    message_properties_reply_to: '${! meta("amqp_reply_to") }'
    message_properties_group_id: '${! meta("amqp_group_id") }'
    message_properties_group_sequence: '${! meta("amqp_group_sequence") }'
    message_properties_reply_to_group_id: '${! meta("amqp_reply_to_group_id") }'
    message_properties_user_id: '${! meta("amqp_user_id") }'
    message_properties_content_type: "application/json"
    message_properties_content_encoding: "utf-8"

For message_properties_message_id and message_properties_correlation_id, the value type is auto-detected: UUID format → AMQP UUID, purely numeric → uint64, otherwise string. This should handle JMS interop well since JMS typically uses string message IDs.

The config above shows a passthrough pattern — reading properties from one AMQP system and forwarding them to another with all standard properties preserved.

[zhlangsas]

Thanks @mmatczuk !