#Services synchronization

If a service has dependencies to other services, it should be started after its dependencies are started.

For example, a ServiceA may be dependent on the ServiceDB. It means that the ServiceA can not be started unless the ServiceDB successfully starts.

It is a part of the Services Synchronization feature to order services based on their dependencies.

#Service Manifest

Each service should export its manifest. The manifest may contain the following information:

• name
• dependencies to other services
• start timeout

WARNING: Currently there is no fail-safe mechanism to handle service startup failure - it will cause non-handled exception SystemInitialisationError{"System startup failed: unable to start a system service."};

Please see: ServiceManifest.hpp to check current defaults

The System Manager needs to read the manifests to run the services in the correct order.

#Synchronization algorithm

The topological sorting algorithm may be used to build a linear ordering of services that are to be started by the System Manager.

Important note: The Dependency Graph implementation handles Directed Acyclic Graphs only.