How to Analyze API RPC Schema

The following instructions can help you analyze an XML API schema.

If you use API RPC 1.4.0.0 or higher:

• Start with the main agent_input.xsd schema. It lists all supported operator elements within the packet element. For example,

  

  On the above figure, complex data type RequestPacketType lists all operator elements supported in API RPC 1.4.0.0. These operators are: server, client, domain, etc. Each operator has a matching request data type (the type attribute). This data type describes the structure of the operator.

• To see the structure of a certain operator, you need to find the low-level 'input' schema where its data type is defined. File agent_input.xsd lists all subsequent schemas as follows:

  

  The schema name contains the name of the operator you need and the _input suffix.

• Open the schema matching any operator. It will contain several complex data types, including the request data type specified for the operator. For example, here is the contents of the client_input.xsd schema (v.1.4.0.0) matching the client operator.

  

  The client operator is described by type ServerOperatorType (highlighted). To see its structure, click the + sign to the left and expand the section.

• Type ServerOperatorType describes the client operator as follows: It lists all operations that can be applied to Plesk Client (get_protos, get, set, srv_man, etc.). The same principle is true for any operator: its request data type (specified in the agent_input.xsd schema) declares operations that can be applied to the relevant object.

  

• Each operation element is also presented by a special data type specified in the type attribute. Operation data types are normally defined in the same schema. For example, the set operation (type AdminSetType) is defined in the same client_input.xsd schema as follows:

  

  All nested elements (operation parameters) are described by specific data types. You can find their definitions either in the same schema, or in the included schema:

  

Thus, when you analyse the schemas, the approach is as follows: start with the main schema to choose the operator and drill down to the subsequent data types that can be found in the included schemas.

If you use API RPC 1.3.5.1 or lower, find the required input schema by its name. The schema describes the structure of the XML packet within the packet element: It contains a single operator element that, in turn, contains some operation elements. Operations are structured as described above: Each operation is a complex data type that contains sequences of various parameters. Some parameters are fully defined within the operation element, others have just a complex data type specified against them. Such data types can be defined in the same schema or in some other schema included into this one with the include directive.