node-bunyan-lite/test/child-behaviour.test.js

/*
 * Copyright (c) 2012 Trent Mick. All rights reserved.
 *
 * Test some `<Logger>.child(...)` behaviour.
 */

var test = require('tap').test;
var bunyan = require('../lib/bunyan');

function CapturingStream(recs) {
  this.recs = recs || [];
}
CapturingStream.prototype.write = function (rec) {
  this.recs.push(rec);
}



test('child can add stream', function (t) {
  var dadStream = new CapturingStream();
  var dad = bunyan.createLogger({
    name: 'surname',
    streams: [{
      type: 'raw',
      stream: dadStream,
      level: 'info'
    }]
  });

  var sonStream = new CapturingStream();
  var son = dad.child({
    component: 'son',
    streams: [{
      type: 'raw',
      stream: sonStream,
      level: 'debug'
    }]
  });

  dad.info('info from dad');
  dad.debug('debug from dad');
  son.debug('debug from son');

  var rec;
  t.equal(dadStream.recs.length, 1);
  rec = dadStream.recs[0];
  t.equal(rec.msg, 'info from dad');
  t.equal(sonStream.recs.length, 1);
  rec = sonStream.recs[0];
  t.equal(rec.msg, 'debug from son');

  t.end();
});


test('child can set level of inherited streams', function (t) {
  var dadStream = new CapturingStream();
  var dad = bunyan.createLogger({
    name: 'surname',
    streams: [{
      type: 'raw',
      stream: dadStream,
      level: 'info'
    }]
  });

  // Intention here is that the inherited `dadStream` logs at 'debug' level
  // for the son.
  var son = dad.child({
    component: 'son',
    level: 'debug'
  });

  dad.info('info from dad');
  dad.debug('debug from dad');
  son.debug('debug from son');

  var rec;
  t.equal(dadStream.recs.length, 2);
  rec = dadStream.recs[0];
  t.equal(rec.msg, 'info from dad');
  rec = dadStream.recs[1];
  t.equal(rec.msg, 'debug from son');

  t.end();
});


test('child can set level of inherited streams and add streams', function (t) {
  var dadStream = new CapturingStream();
  var dad = bunyan.createLogger({
    name: 'surname',
    streams: [{
      type: 'raw',
      stream: dadStream,
      level: 'info'
    }]
  });

  // Intention here is that the inherited `dadStream` logs at 'debug' level
  // for the son.
  var sonStream = new CapturingStream();
  var son = dad.child({
    component: 'son',
    level: 'trace',
    streams: [{
      type: 'raw',
      stream: sonStream,
      level: 'debug'
    }]
  });

  dad.info('info from dad');
  dad.trace('trace from dad');
  son.trace('trace from son');
  son.debug('debug from son');

  t.equal(dadStream.recs.length, 3);
  t.equal(dadStream.recs[0].msg, 'info from dad');
  t.equal(dadStream.recs[1].msg, 'trace from son');
  t.equal(dadStream.recs[2].msg, 'debug from son');

  t.equal(sonStream.recs.length, 1);
  t.equal(sonStream.recs[0].msg, 'debug from son');

  t.end();
});