The source application component is any application that uses the logback framework for logging arbitrary log messages. For our purposes, we will create a simple application that logs structured messages at certain intervals. However, as you'll see, any existing application that uses either the logback or slf4j frameworks can be substituted with a simple configuration change.

The logback framework has an extension mechanism that allows you to add additional appenders to its configuration. A logback appender is simply a Java class that receives logging events and does something with them. The most commonly used appenders are one of several FileAppender subclasses that simply format and write log messages to a file on disk. Other appender implementations write log data to network sockets, relational databases, and...