Web handlers have been available in PASOE since 11.6.0 and are an easy – for the ABL programmer – way of adding a REST API to an application. Web handlers give programmers many options, but they also require that the ABL code deal with most aspects of the request and response, including conversion from “HTTP” to “ABL” (or even “4GL” if you’re that way inclined) and back again. An application may have one web handler per business service, or just one for the application, or something in between.
This workshop discusses how to decide on approaches for how many web handlers your application needs, how to write a web handler – covering content types, strategies for error handling and status codes, routing requests and more – and also covers topics like deployment and authorization.
