Middleware Layer

This Open Semantic Framework stack may be controlled or interacted with via external services at the middleware layer. Some of this interaction may occur via a dedicated API, some programmatically.

The OSF Web Sevices PHP API is a framework available to PHP developers to help them generate queries to any OSF Web Service endpoint. Each endpoint has its own WebServiceQuery class in the API that is used to generate the query, send it to the appropriate endpoint, and get back a resultset. The resultset can then be manipulated by using the Resultset API. This same API can be used to transform the resultset into different formats.

The OSF Web Services PHP API enables developers to write function calls directly in PHP that then issue the HTTP queries to the respective OSF Web Service endpoints. It is also the API interace for other Drupal modules and connectors (see the OSF for Drupal overview) to programmatically interact with the Web service endpoints. This same design can be replicated in other languages (such as Java, etc.).

It is via the middleware layer that security and external services may also interact with the system. In these areas specific APIs are not available, but programmatically other external systems have been successfully interfaced in the past.

For security, it is possible to either use the native OSF service or invoke an external system. Additional experience with incorporating other external applications in authoring, version control or harvesting are also documented at the middleware layer.