Introduction to Stateless API Scripts in System Platform

This help shows you how to use the MES Stateless API.

The new API libraries in the current version of MES offers a more structural hierarchy and provide the flexibility to work on a specific API that is licensed, rather than listing all the API's in a single library.

The MES APIs are grouped under the following types:

• MES Stateful APIs
• MES Stateless APIs

The Stateless API is designed for more complex applications that require access to the full range of calls available within MES.

The Stateless APIs interact with the database through the middleware to perform database operations. The Stateless API does not hold any contextual data. When an API method is called, it passes the necessary information to the middleware along with the supplied information if any, and returns the result back to the caller. Any error during the execution of the Stateless API is sent back to the caller, and it puts the onus on the caller to handle all the errors raised by the Stateless APIs.

There are Base Level Classes which generally map to a table in the MES database. The Base Level Classes contain methods for standard table functions, such as Add, Update, Insert, Delete, and Select along with specific functional methods associated with the table. Each base level class exposes the following standard methods:

• Add
• Update
• UpdateSpecific
• Delete
• DeleteAll
• GetAll
• GetByKey

These methods interact directly with the table in the database and are subject to any constraints placed on the table. Any additional methods may interact with other tables in the database. This help file does not list the specific table interactions.

This topic shows how to:

Stateless API Wrapper

Installing the Stateless API Wrapper in System Platform

Installing the Stateless API Wrapper for Visual Studio

Using the Stateless API Functions

Using the DB Data Types Conversion Methods

Result Object (aaMES.Result)

General Coding Comments

Using the API call from System Platform

Overloads

Result Properties Table