Building REST services with WebHandlers on PASOE

The course starts with an overview and what a REST service is, together with REST’s relationship to HTTP. What an HTTP request and response consists of is discussed, including HTTP methods, status codes and key headers. In addition, a common design approach and basic style guide for REST services is outlined before moving on to implementing REST services in OpenEdge, which will include the following topics:

• options for creating REST services with OpenEdge
• REST services with the DataObjectHandler (Business Entities)
• JSON Filter Pattern
• how to return validation errors from a Business Entity
• custom methods in Business Entities
• custom HTTP responses from Business Entities
• support for JSDOs
• use of custom WebHandlers
• evaluating HTTP requests (paths, path and query parameters)
• creating and sending HTTP responses (text & binary data)
• uploading single or multiple files
• detecting and handling invalid requests
• options for versioning REST services
• WebHandler deployment

The course is taught on an up-to-date version of OpenEdge, with an emphasis on hands-on exercises carried out by the attendees. Attendees will be provided with course and exercise notes and final solutions to the exercises.