Deprecate `console.log` in favor of node-bunyan.

deprecate-console-test.js

var deprecate = require('depd')('bunyan')
  , bunyan = require('bunyan')
  ;

// Bunyan logger used by the app.
var logger = bunyan.createLogger({ name:'app', level:'debug' });

// Bunyan logger to catch only the console.
var depdconsole = bunyan.createLogger({ name:'console', level:'warn' });

// Overwrite `process.stderr.write` which is used by depd to log warnings.
// I'm not sure this is a good idea.
process.stderr.isTTY = false;
process.stderr.write = function(message){
  depdconsole.warn(message.replace(/(.*)GMT\s(.*)\n/g, '$2'));
};

// Deprecate `console.log` and use the Bunyan instance.
console.log = deprecate.function(function(){
  logger.info.apply(logger, arguments);
}, 'console.log');

// Legacy code not yet updated to Bunyan.
console.log('Hello %s!', 'World');

output.json

{"name":"console","hostname":"flesch.local","pid":3893,"level":40,"msg":"bunyan deprecated console.log at module.js:456:26","time":"2014-11-20T17:43:07.642Z","v":0}
{"name":"app","hostname":"flesch.local","pid":3893,"level":30,"msg":"Hello World!","time":"2014-11-20T17:43:07.645Z","v":0}