The following specification defines the Data Mapper JSON schema of WSO2 ESB. It is intended to be the authoritative specification. Implementations of schemas for the Data Mapper mediator must adhere to this.
Schema declaration
A schema is represented in JSON by one of:
- A JSON string, naming a defined type.
- A JSON object, of the form:
{"type": "typeName" ...attributes...}
, wheretypeName
is either a primitive or a derived type name, as defined below. - A JSON array, representing a union of embedded types.
A WSO2 ESB Data Mapper schema should start with the $schema
attribute with the WSO2 Data Mapper schema version. For example: { “$schema”:”http://wso2-data-mapper-json-schema/1.0v”}
Also, it can contain following optional attributes that will define more information about the schema.
- “id”: a JSON string declaring a unique identifier for the schema.
- “title”: a JSON string defining the root element name.
- “description”: a JSON string providing a detailed description about the schema.
- “type”: a JSON string providing the element type.
- “namespaces”: a JSON array of JSON objects defining namespaces and prefix values used in the schema as shown in the following example.
{ “$schema” : ”http://wso2-data-mapper-json-schema/1.0v”, “id”:”http://wso2-data-mapper-json-schema-sample-o1”, “title”:”RootElement”, "type":"object", “description”:”This schema represent any form of object without any restriction” , "namespaces":[ { "prefix":"ns1", "url":"http://ns1.com"}, {"prefix":"ns2", "url":"http://ns2.com"}] }
Primitive types
Primitive types have no specified attributes. The set of primitive type names are as follows.
- null: no value
- boolean: a binary value
- integer: integer value
- number: rational numbers
- string: unicode character sequence
Primitive type names are also defined type names. Thus, for example, the schema "string" is equivalent to: {"type": "string"}