Message Schema

Summary

This page provides details to implement the Azure Service Bus Message Schema. The properties have been extracted from the official Microsoft Azure Source.

Data Contract

Data Contracts are common during message interchange between systems. A data contract is a formal agreement between a Sender and a Receiver which describes the data and any associated metadata to be exchanged. This removes any impedance mismatch because both the Sender and Receiver have agreed on the message format.

Message Format

A typical message will consist of three parts; Header, Parameters and Body. Protocols such as HTTP, AMQP, and SOAP will construct messages differently and use these properties during message exchange.

Message Types

A message during an exchange can fall into the following categories: Command, Event, Query & Document. More information is available here.

Schema Registry

A Schema Registry is a registry that holds a catalogue of message formats. These schemas can be used by the Sender during message construction to create the message object. Because the message schema defines the properties of the message, the Sender must strictly adhere to the schema. The Receiver will then use the same schema registry during message transformation; i.e. taking an existing serialised message and then de-serialising it to a message that is meaningful to the Receiver.

Azure Service Bus Schema Definition

Message Properties

ServiceBusSender sender = client.CreateSender(queue);

ServiceBusMessage message = new ServiceBusMessage
{
    Message​Id = new Guid().ToString(),
    Subject = "Order 2007463",
    ContentType = "application/json",
    CorrelationId = new Guid().ToString(),
    TimeToLive = TimeSpan.FromSeconds(600)
};

await sender.SendMessageAsync(message

Message Payload

{  
    "employee": {  
        "name":       "sonoo",   
        "salary":      56000,   
        "married":    true  
    }  
}