Add request logging

[sapessi]

• Framework version: 1.0
• Implementations: Jersey / Spring / Spring Boot / Spark

Scenario

Log each request using Apache's combined log format or JSON objects (containing the same values).

Apache

LogFormat "%h %l %u %t \"%r\" %>s %b \"%{Referer}i\" \"%{User-agent}i\"" combined
127.0.0.1 - frank [10/Oct/2000:13:55:36 -0700] "GET /apache_pb.gif HTTP/1.0" 200 2326 "http://www.example.com/start.html" "Mozilla/4.08 [en] (Win98; I ;Nav)" 

Add a configuration variable to specify whether the logs should be in string or json format.

[sapessi]

Added request logging to LambdaContainerHandler object. The format of the log line is dictated by an implementation for the LogFormatter interface.

You can configure custom formatters on the container handler object:

handler.setLogFormatter(new MyCustomLogFormatter<>());

By default we include the ApacheCombinedServletLogFormatter implementation. This is automatically set when we initialized a AwsLambdaServletContainerHandler - currently used in all implementations.

Still outstanding is to add the documentation.

[sapessi]

Docs pushed to the next-release branch of the wiki (hidden at the moment).