Lens server components
Lens server comes up with embedded http server. It offers services for session management, metastore and query.
Here is the diagram describing all the components:
Lens services
Session service
Allows user to start a session, close a session, add/delete resources in session, set session level parameters.
Metastore service
Allows user to do crud on cubes, fact tables, dimension tables, partitions. Administrator would be managing the storages available. So, all the crud for storages will be done by administrator. See Storages API and Storage API for details.
Metastore service talks to Hive metastore server.Hive metastore server end point has to be configured for lens server.
Query service
Allows user to launch query, monitor the query and get results. User can also look at history of his queries.
Lens server allows pluggable execution drivers for running queries. Available execution engines are Hive and JDBC. For configuring Hive as an execution engine, administrator should configure the HiveServer2 end point. More details on configuring multiple drivers will be covered in configuration guide