...

• The client could be either a CLI or a Web Service
• A gateway component that exposes a JSON RPC API and interacts with the rest of the system through the internal's system protocol
• A database component which stores the data being used
• A scheduler component that organizes the projects and assigns jobs to the observing mode
• An observing mode which abstracts an observation entirely

There are a couple of use cases the system should allow:

• Add new science projects
  • User interacts with CLI / WS
  • CLI / WS connects through JSON RPC API method XXXX with Gateway Component
  • Gateway Component interacts with Database Component to add the new science project
• Remove science projects only if they haven't been observed yet (and are not being observed).
  • User interacts with CLI / WS
  • CLI / WS connects through JSON RPC API method XXXX with Gateway Component
  • Gateway Component interacts with Database Component to remove science project
    • Database Component removes the science project if possible
    • Database Component should raise an exception if the project is being observed or has already been observed
• Retrieve next N projects
  • User interacts with CLI / WS
  • CLI / WS connects through JSON RPC API method XXXX with Gateway Component
  • Gateway Component interacts with Scheduling Component and requests the next 10 projects to be observed
    
• Schedule projects
  • Scheduling Component regularly checks the available projects with the Database Component
  • If there are projects available, then it prioritizes them and queues them in an internal list
  • A different thread is regularly checking with the Observing Mode component whether it is able to observe
    • If the Observing Mode component is IDLE, then the Scheduling Component sends an observation request
• Observe project
  • The Observing Mode component is a very simple participant that receives a request to observe
    • If it is already observing it should raise an exception
    • Otherwise it should mark the project as "Running" with the Database Component and start the observation
      • It should simulate the observation by waiting a configured time in the project
      • Once it finishes it should mark the project as either "Success" or "Failure" with the Database Component

Interface

ObservingMode Component

...