Service Logging

[osxhacker]

The microservices currently support Logstash JSON log events via the net.logstash.logback.layout.LogstashLayout class. Also, minimal context is provided by each subsystem with the ContextualLoggerFactory type.

The purpose of this enhancement is to ensure consistent configuration of the logging subsystem and to establish best practices for:

• [x] Identifying what is expected in each subsystem's minimal logging context.
• [x] Specifying the expectations for when to use each log level.
• [x] Refactor where needed existing log usage.
• [x] Document examples of common logging practices.

[osxhacker]

Grafana Loki does not support JSON fields which have separators (such as . or -). Fortunately, Logstash supports transforming JSON log events.

Included in this effort is additional configuration and documentation which captures what must be done to transform ECS in logstash into JSON objects which Loki can successfully ingest.

[osxhacker]

During the effort to standardize logging, the functional Aspect Oriented Programming component required enhancements to better model functional programming techniques. As such, this enhancement contains them as well.