API Logging in Json format

Question

I would like to log API request/response as json format.

The expected LogEntry is something like

{ 
 "timestamp" : "...",
 "level" : "DEBUG",
 "headers" : [
    "header1" : "value1",
    "header2" : "value2",
    "header3" : "value3"
 ],
 "requestPayload" : "<Request Json>"   // prefereablly as sub-document, worst case string is fine.   
 "labels" : [        //key fields which can be used for searching the logentry
     "searchField1" : "....",
     "searchField2" : "....",
     "searchField3" : "...."
  ]
}

My Question is :

Using Logback, How to log nested fields (e.g. headers, labels, requestPaylod in above example), as json sub-document. I tried MDC, but its limited to Map of 'String, String' only, and considers all fields after first level as String.

I hate to write my custom logger for this, and would like to use the goodness of proven logging frameworks(logback/log4j) to control the logging level, time stamping log event, etc.

Answer 1

For request/response logging try Logbook and logstash-logback-encoder. You'll be able to use Markers to add structured contents.

For adding 'your own' fields in a JSON structure, I've written a code generator you might find interesting, it adds builder support: json-log-domain