Getting Started

This section provides an overview of how to get starting with developing a LightWave Client application. If you have not done so already, please read the Introduction to LightWave Client section before continuing.

LightWave Client provides access to REST APIs through the familiar NonStop interprocess message system. Your client application constructs an interprocess message (IPM) formatted according to a definition generated by LightWave Client. Your application then sends the IPM (using COBOL "SEND", or the SERVERCLASS_SEND_ or WRITEREAD[X|64] system procedures) to the LightWave Client Process, which transforms the IPM content into an HTTP message formatted as required by the REST/web API and sends it to the service endpoint. When the service completes, LightWave Client receives the response and transforms the content into an IPM which is then replied to your client application.

Client applications can be coded in any programming language supported on HPE NonStop.

The maximum interprocess message size supported by LightWave Client is the same as the maximum message size supported by the Guardian message system for process servers, and NonStop TS/MP Pathsend for Pathway serverclasses. The maximum message size is typically 2MB (2097152 bytes) on modern NonStop systems, but may vary depending on NonStop software versions and the application language in use.

These are the steps required to develop a client application:

• Using the Console, create the API definition for the service you wish to access:

  • Import a definition in OpenAPI (a/k/a Swagger) format that is provided by the service owner, or

  • Create the definition using the API Editor together with sample requests and responses provided by the service owner

• Generate the API interface IPMs to be used by your application

  • Using the Console, generate DDL source for the IPMs

  • Load generated DDL source into a DDL dictionary

  • Generate language-specific header files

• Create code in your application to call the service using the IPMs defined in the header files.

  • Include the generated header file

  • set the 'method alias' and any API-specific parameters

  • send the request IPM to the LightWave Client Process

• Run the application

  • Configure and start the LightWave Client Process Instance

  • Run your client application