Appendix D: Internal Adapter API

If the adapters available from SAP do not meet your needs, Event Stream Processor provides an internal adapter API that you can use to build internal adapters. However, with the addition of the ESP adapter toolkit, the internal API is being deprecated and may be removed in future releases of Event Stream Processor. It is highly recommended that you get familiar with and use the ESP adapter toolkit instead.

As part of creating a custom internal adapter, you must also create a custom adapter library. This library uses the Event Stream Processor shared utility library to help convert external data to ESP Server format.

You can implement life cycle and information management functions for your custom adapter using the C APIs provided by the adapter shared utility library. You can use the C interface to implement your custom adapter in C or C++ without any compiler restrictions.

The header file, GenericAdapterInterface.h, contains the import declarations that are required to call utility functions in the adapter shared utility library.

The Adapter Shared Utility Library
The adapter shared utility library provides the utility functions required for a custom adapter implementation, including data conversion, data manipulation, and data management.
Sample Model File
Sample syntax you can use to build a basic model file.
The Adapter Configuration File
The internal adapter configuration file is an XML file (.cnxml) that contains the properties and commands used by ESP to start and stop the internal adapter, as well as other information that allows the internal adapter to be configured from the ESP Studio.
DLL Export Functions
The DLL export functions define how a custom internal adapter controls its life cycle and communicates with the ESP Server. These functions must be implemented and exported in the DLL.
DLL Import Functions
A custom internal adapter can import DLL import functions, which provide useful functionalities for implementing a custom adapter.
Adapter Run States
Adapters progress through a set of run states (RS) as they interact with Event Stream Processor.
Sample Custom Internal Adapter Implementation
Sample syntax you can use to build your custom internal adapter implementation. This implementation incorporates extern "C" methods that enable schema discovery in a custom adapter.