Combining Subschemas

In this module, you will learn how to combine multiple subschemas to create more complex JSON Schemas. You will learn about the following keywords: allOf, anyOf, oneOf, not, $defs,$ref and recursive schemas.

$defs and $ref

In JSON Schema, the $defs keyword allows you to define reusable subschemas. You can then reference these subschemas using the $ref keyword.

To define a subschema with $defs, you can use the following syntax:

1{
2  "$defs": {
3    "mySubschema": {
4      "type": "string",
5      "maxLength": 10
6    }
7  }
8}

In the above example, we define a subschema named mySubschema which specifies that the value should be a string with a maximum length of 10 characters.

To reference this subschema using $ref, you can use the following syntax:

1{
2  "$ref": "#/$defs/mySubschema"
3}

In the above example, we reference the mySubschema subschema using $ref. This allows us to reuse the definition of mySubschema wherever we need it.

Using $defs and $ref can help make your JSON Schema more modular and maintainable by promoting code reuse.

Task

1{
2  "name":{
3    "firstName":"John",
4    "middleName":"Smith",
5    "lastName":"Doe"
6  }
7}

Define a subschema named stringType in the schema given in side editor, which is just "type": "string" and then reference it using $ref for the properties firstName, middleName and lastName