Regardless of the logging framework in use (Microsoft.Extension.Logging, Serilog, Log4net, NLog, …), logger fields should be:
- private: this restricts access to the logger from outside the enclosing type (class, struct, record…). Using any other access
modifier would allow other types to use the logger to log messages in the type where it’s defined.
- static: making the logger field
static will ensure that the lifetime of the object doesn’t depend on the lifetime
of the instance of the enclosing type.
- readonly: marking the field as
readonly will prevent modifications to the reference of the logger. This ensures
that the reference to the logger remains consistent and doesn’t get accidentally reassigned during the lifetime of the enclosing type.
This rule should be activated when Service Locator Design pattern is followed
in place of Dependency Injection for logging.
The rule supports the most popular logging frameworks:
