use bunyan-logger-factory

use-bunyan-logger-factory.js

"use strict";

/**
 * on Mac you can use system builtin app Console to view syslog
 * but logProto has to be 'sys'
 * Note, Console only shows logs with level >= warn by default
 *
 *
 * fatal 60
 * error 50
 * warn 40
 * info 30
 * debug 20
 * trace 10
 */

const loggerFactory = require("bunyan-logger-factory");

const loggerFile = loggerFactory.init({
  logName: "filefoo",
  logStream: "stdout"
});

const loggerSyslog = loggerFactory.init({
  logName: "foo",
  logStream: "SYSLOG",
  logHost: "127.0.0.1",
  logPort: 514,
  // type LogProto = 'sys' | 'tcp'
  logProto: "sys"
});

const o = {
  name: "foo",
  num: 123,
  createdAt: new Date(),
  a: {
    b: {
      c: {
        d: "d"
      }
    }
  }
};

const err = new Error("bar");

const logger = loggerSyslog;


logger.warn("a%sc", 'b');
// {"name":"foo","hostname":"juno.lan","pid":46680,"level":40,"msg":"abc","time":"2020-02-12T09:49:22.433Z","v":0}

////////// logger can expand object nicely if it's the first param

logger.warn(o, "xxx warn");
// {"name":"foo","hostname":"juno.lan","pid":46227,"level":40,"num":123,"createdAt":"2020-02-12T09:44:49.654Z","a":{"b":{"c":{"d":"d"}}},"msg":"xxx warn","time":"2020-02-12T09:44:49.654Z","v":0}
logger.warn({ o }, "xxx warn");
// {"name":"foo","hostname":"juno.lan","pid":46227,"level":40,"o":{"name":"foo","num":123,"createdAt":"2020-02-12T09:44:49.654Z","a":{"b":{"c":{"d":"d"}}}},"msg":"xxx warn","time":"2020-02-12T09:44:49.656Z","v":0}
logger.warn("xxx warn", o); // won't work
// {"name":"foo","hostname":"juno.lan","pid":46326,"level":40,"msg":"xxx warn {\n  name: 'foo',\n  num: 123,\n  createdAt: 2020-02-12T09:45:53.104Z,\n  a: { b: { c: [Object] } }\n}","time":"2020-02-12T09:45:53.110Z","v":0}

////////// "err" is a magic prop, "error" wont work

logger.warn({ err: err }, "xxx warn"); // set NODE_ENV to 'production' before creating logger to remove the stack trace in log
// {"name":"foo","hostname":"juno.lan","pid":46069,"level":40,"err":{"message":"bar","name":"Error","stack":"Error: bar\n    at Object.<anonymous> (/Users/haishan/t/bunyan-logger-factory0/app.js:46:13)\n    at Module._compile (internal/modules/cjs/loader.js:959:30)\n    at Object.Module._extensions..js (internal/modules/cjs/loader.js:995:10)\n    at Module.load (internal/modules/cjs/loader.js:815:32)\n    at Function.Module._load (internal/modules/cjs/loader.js:727:14)\n    at Function.Module.runMain (internal/modules/cjs/loader.js:1047:10)\n    at internal/main/run_main_module.js:17:11"},"msg":"xxx warn","time":"2020-02-12T09:43:03.403Z","v":0}
logger.warn({ error: err }, "xxx warn");
// {"name":"foo","hostname":"juno.lan","pid":45929,"level":40,"error":{},"msg":"warn","time":"2020-02-12T09:41:24.598Z","v":0}