Microsoft Information Protection SDK - Observer concepts

The MIP SDK is designed to be almost entirely asynchronous. For example, any operation resulting in network or file IO is performed asynchronously. To handle the event notifications for these asynchronous events, the SDK makes use of the observer pattern.

Implementation overview

When constructing an object that will perform an asynchronous operation, an Observer class must be implemented. Observers will receive the notification events related to the various asynchronous operations in the MIP SDK, and provide the result to the caller.

Functions in each Observer class are virtual and are overridden for the preferred asynchronous pattern. The SDK implements the event notification observer pattern via std::promise and std::future.

Each class-specific observer contains a set of success and error/failure functions, for the outcome of an async operation. Success functions return the object associated with the operation. Error/Failure functions return an exception that contains details on why the operation was unsuccessful.

As an example, FileProfile supports the following two operations:

  • It can add a new engine to the profile via FileProfile::AddEngineAsync.
  • It can unload an engine from the profile via FileProfile::UnloadEngineAsync.

Since two Observer functions are implemented per asynchronous operation, it can be assumed that there are four Observer methods associated with FileProfile:

  • FileProfileObserver::OnAddEngineSuccess()
  • FileProfileObserver::OnAddEngineError()
  • FileProfileObserver::OnUnloadEngineSuccess
  • FileProfileObserver::OnUnloadEngineError().

MIP SDK Observer Classes

The MIP SDK File API contains two observers:

  • mip::FileProfile::Observer
  • mip::FileHandler::Observer

The MIP SDK Policy API has just a single observer:

  • mip::Profile::Observer

The MIP SDK Protection API has three observers:

  • mip::ProtectionProfile::Observer
  • mip::ProtectionEngine::Observer
  • mip::ProtectionHandler::Observer

Next Steps

Learn more about how observers are implemented and used, by the various APIs: