Is it a good idea to include schema name in JSON document - json

Question

We are developing a public service that ingests JSON messages to be stored in the database.
Now this service is probably the first of many, and I'm working on a way to structure the JSON Schemas. We have a lot of experience with XML Schema, but JSON Schema is a bit new to us.
One the the ideas is to include a Header section into each JSON Schema that contains the schema name, the major version and a unique message ID
Here's a simplified version of such a schema
{
"$schema": "http://json-schema.org/draft-04/schema#",
"id": "http://www.example.com/json/01/sampleMessage",
"type": "object",
"title": "Sample Message for stackoverflow",
"description": "version 01.01",
"properties": {
"Header": {
"$ref": "#/definitions/Header"
},
"EanGsrn": {
"description": "Unique identifier of the Headpoint.",
"type": "string",
"pattern": "^[0-9]{18}$"
},
"Sector": {
"description": "Sector for which the Headpoint is valid.",
"type": "string",
"enum": [
"Electricity", "Gas"
]
}
},
"additionalProperties": false,
"required": [
"Header", "EanGsrn", "Sector"
],
"definitions": {
"Header": {
"id": "#Header",
"type": "object",
"description": "Standard header for all messages",
"properties": {
"Schema": {
"description": "$id of the schema of this message",
"type": "string",
"enum": ["http://www.example.com/json/01/sampleMessage"]
},
"Version": {
"description": "The specific version of the shema of this message",
"type": "string",
"pattern": "^01\\.[0-9]{2,3}$"
},
"MessageId": {
"description": "Unique identifier for the Message",
"type": "string",
"pattern": "^[a-f0-9]{8}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{12}$"
}
},
"required": [
"Schema", "Version", "MessageId"
],
"additionalProperties": false
}
}
}
The advantages of this should be:
A message for the wrong schema or major version would be rejected immediately at the schema validation step.
The JSON itself contains information about it's schema and version, making life easier for the people needing to investigate issues etc... later on.
Questions
Is this usual, or are there other best practices in the JSON world to handle things like this?
Is this a good idea, of am I missing something obvious here?

Answer 1

There is no "best practice" for defining how a JSON instance identifies the schema it should conform to outside of an HTTP request.
The spec provides a header name to define the schema, but this only works if your JSON data is always served over HTTP.
Other systems similar to yours have included this information in the JSON data as a header like section, but there's no defined "best practice" or approach which the specification itself details.