binder-logging

binder-logging

Consistent logging reader/writer functions for all Node-based Binder modules

Takes a configuration file (the default version in conf/example.main) that specifies how to

• connect to a Logstash server for log writing
• connect to Elasticsearch/Kibana servers for log reading
• stream build logs from a websocket

The example configuration file included in the module has these defaults:

{
  "host": "localhost",
  "testing": true,
  "logstash": {
    "port": 8050,
    "configDir": "~/binder-control/services/logging/logstash/"
  },

  "elasticsearch": {
    "port": 8052,
    "dir": "/data/binder/elasticsearch"
  },

  "kibana": {
    "port": 8053
  },

  "streaming": {
    "port": 2121
  }
}

binder-control can launch Docker containers for Elasticsearch, Logstash and Kibana (with the same default values) through the binder-control start-service logging command. If you'd prefer to use existing logging infrastructure, specify the custom host/port in the config file.

If testing is enabled, the Winston logger will output to both Logstash and stdout (only Logstash otherwise).

install

npm install binder-logging

reader

lib/reader.js contains functions that wrap Elasticsearch queries to make it simpler to search through Binder logs. If you'd prefer to monitor a realtime stream of build logs, the streamLogs function is available (which will connect to Logstash's WebSocket output).

BinderLogReader.getLogs(opts, cb)

Get all historical logs, optionally matching an app name and optionally between before/after times

• app string - app name to filter on
• before string - ISO8601 GMT timestamp
• after string - ISO8601 GMT timestamp
• cb function - callback(err, msgs)

BinderLogReader.streamLogs(opts)

Stream logs for a given app (mandatory option), optionally since an after timestamp. Returns a through stream

• app string - app name to filter on
• after string - ISO8601 GMT timestamp

usage

var getReader = require('binder-logging/lib/reader')
var reader = getReader({ host: '<custom logging host>' })

writer

lib/writer.js exposes a getInstance function that will return a Winston logger given a logger name. This logger exposes the standard logging api (logger.info, logger.error, ...).

getInstance(name)

Returns a Winston logger that's connected to the Binder logging stack

• name string - logger name (one logger will be created per name, per process)

usage

var getLogger = require('binder-logging/lib/writer')
var logger = getLogger('<logger name>')
logger.info('this is an info message')