The EDMapplicationServer
- Ivar Nor (Unlicensed)
EDMthinClient / EDMsixServer communication is said to be stateless, but that is not entirely true. In fact, the EDMsixServer is not able to handle stateless requests from clients. The explanation is that the EDMthinClients do not pass their calls to the EDMsixServer at all. Between the EDMthinClient and the EDMsixServer, there is a third component named the EDMapplicationServer. An EDMsixServer may have any number of EDMapplicationServers to handle the incoming requests from EDMthinClients. The EDMapplicationServer is actually what we may call an EDMfatClient. It retains a stateful connection to the EDMsixServer and send function calls on behalf of the EDMthinClient.
The EDMapplicationServer is an EDMfatClient application that has access to the same file system as the EDMsixServer. It receives EDMremoteInterface API function parameter sets and server contexts from the EDMthinClients and sends them to the EDMsixServer through its stateful connect. Without the EDMapplicationServer, the EDMthinClients cannot access the EDMsixServer at all.
The EDMfatClient maintains a working copy of the EDMdatabase files required for its tasks.
When drawing system diagrams for EDMsix, a simplified block is used to represent the EDMapplicationServer.
The EDMapplicationServer interconnects the EDMthinClient and the EDMsixServer
The EDMapplicationServer connects statefully to the EDMsixServer as shown in the diagram below