Create a custom JSON schema

According to its file content, every OA document follows a particular structure that makes it valid. To ensure the document adheres to the structure, you can create a custom schema to use the document as a validation upon the wrapping process.

This guide will show you how to create a custom schema.

Document (invoice)

The document below is used as an example in subsequent sections for creating an OA document.

JSON schema

A custom schema for the Invoice document is in the code example below.

{
  "$id": "https://example.com/invoice/1.0/schema.json",
  "$schema": "http://json-schema.org/draft-07/schema#",
  "type": "object",
  "title": "Description of data expected for invoices",
  "required": ["id"],
  "properties": {
    "id": {
      "type": "string"
    },
    "date": {
      "type": "string"
    },
    "customerId": {
      "type": "string"
    },
    "terms": {
      "type": "string"
    },
    "subtotal": {
      "type": "string"
    },
    "tax": {
      "type": "string"
    },
    "taxTotal": {
      "type": "string"
    },
    "total": {
      "type": "string"
    },
    "billFrom": {
      "type": "object",
      "properties": {
        "name": {
          "type": "string"
        },
        "streetAddress": {
          "type": "string"
        },
        "city": {
          "type": "string"
        },
        "postalCode": {
          "type": "string"
        },
        "phoneNumber": {
          "type": "string"
        }
      }
    }
    // other properties
  }
}

It contains the following variables:

Variable	Necessity	Definition
$id	Required	URI location of where the schema resides.
$schema	Optional	JSON schema vocabulary.
type	Optional	Data type of the schema.
title	Optional	Description of what the schema represents.
required	Optional	Whether some properties are required for the document. If the properties stated here do not exist in the properties variable, an error will occur during validation.
properties	Optional	Properties of the document and their respective data types. If the document contains any fields that do not conform to what is defined here, an error will occur during validation.

Usage

Once you have created a custom schema for the document, you can use it during the wrapping process for validation.

Additional reading

To learn more about the wrapping process, see this guide.