# fluent-logger for Node.js fluent-logger implementation for Node.js inspired by [fluent-logger-python]. [![NPM](https://nodei.co/npm/fluent-logger.png?downloads=true&downloadRank=true)](https://nodei.co/npm/fluent-logger/) [![Build Status](https://secure.travis-ci.org/fluent/fluent-logger-node.png?branch=master,develop)](http://travis-ci.org/fluent/fluent-logger-node) ## Install $ npm install fluent-logger ## Prerequistes Fluent daemon should listen on TCP port. Simple configuration is following: ```aconf @type forward port 24224 @type stdout ``` ## Usage ### Send an event record to Fluentd Singleton style ```js var logger = require('fluent-logger') // The 2nd argument can be omitted. Here is a default value for options. logger.configure('tag_prefix', { host: 'localhost', port: 24224, timeout: 3.0, reconnectInterval: 600000 // 10 minutes }); // send an event record with 'tag.label' logger.emit('label', {record: 'this is a log'}); ``` Instance style ```js var logger = require('fluent-logger').createFluentSender('tag_prefix', { host: 'localhost', port: 24224, timeout: 3.0, reconnectInterval: 600000 // 10 minutes }); ``` The emit method has following signature ```js .emit([label string], , [timestamp number/date], [callback function]) ``` Where only the `record` argument is required. If the label is set it will be appended to the configured tag. ### Disable automatic reconnect Both Singleton and Instance style can disable automatic reconnect allowing the user to handle reconnect himself ```js logger.configure('tag_prefix', { host: 'localhost', port: 24224, timeout: 3.0, enableReconnect: false // defaults to true }); ``` ### Shared key authentication Logger configuration: ```js var logger = require('fluent-logger').createFluentSender('dummy', { host: 'localhost', port: 24224, timeout: 3.0, reconnectInterval: 600000, // 10 minutes security: { clientHostname: "client.localdomain", sharedKey: "secure_communication_is_awesome" } }); logger.emit('debug', { message: 'This is a message' }); ``` Server configuration: ```aconf @type forward port 24224 self_hostname input.testing.local shared_key secure_communication_is_awesome @type stdout ``` See also [Fluentd](https://github.com/fluent/fluentd) examples. ### TLS/SSL encryption Logger configuration: ```js var logger = require('fluent-logger').createFluentSender('dummy', { host: 'localhost', port: 24224, timeout: 3.0, reconnectInterval: 600000, // 10 minutes security: { clientHostname: "client.localdomain", sharedKey: "secure_communication_is_awesome" }, tls: true, tlsOptions: { ca: fs.readFileSync('/path/to/ca_cert.pem') } }); logger.emit('debug', { message: 'This is a message' }); ``` Server configuration: ```aconf @type forward port 24224 ca_cert_path /path/to/ca_cert.pem ca_private_key_path /path/to/ca_key.pem ca_private_key_passphrase very_secret_passphrase self_hostname input.testing.local shared_key secure_communication_is_awesome @type stdout ``` FYI: You can generate certificates using fluent-ca-generate command since Fluentd 1.1.0. See also [How to enable TLS/SSL encryption](https://docs.fluentd.org/input/forward#how-to-enable-tls-encryption). ### Mutual TLS Authentication Logger configuration: ```js var logger = require('fluent-logger').createFluentSender('dummy', { host: 'localhost', port: 24224, timeout: 3.0, reconnectInterval: 600000, // 10 minutes security: { clientHostname: "client.localdomain", sharedKey: "secure_communication_is_awesome" }, tls: true, tlsOptions: { ca: fs.readFileSync('/path/to/ca_cert.pem'), cert: fs.readFileSync('/path/to/client-cert.pem'), key: fs.readFileSync('/path/to/client-key.pem'), passphrase: 'very-secret' } }); logger.emit('debug', { message: 'This is a message' }); ``` Server configuration: ```aconf @type forward port 24224 ca_path /path/to/ca-cert.pem cert_path /path/to/server-cert.pem private_key_path /path/to/server-key.pem private_key_passphrase very_secret_passphrase client_cert_auth true self_hostname input.testing.local shared_key secure_communication_is_awesome @type stdout ``` ### EventTime support We can also specify [EventTime](https://github.com/fluent/fluentd/wiki/Forward-Protocol-Specification-v1#eventtime-ext-format) as timestamp. ```js var FluentLogger = require('fluent-logger'); var EventTime = FluentLogger.EventTime; var logger = FluentLogger.createFluentSender('tag_prefix', { var eventTime = new EventTime(1489547207, 745003500); // 2017-03-15 12:06:47 +0900 logger.emit('tag', { message: 'This is a message' }, eventTime); ``` ### Events * `connect` : Handle [net.Socket Event: connect](https://nodejs.org/api/net.html#net_event_connect) * `error` : Handle [net.Socket Event: error](https://nodejs.org/api/net.html#net_event_error_1) ```js var logger = require('fluent-logger').createFluentSender('tag_prefix', { host: 'localhost', port: 24224, timeout: 3.0, reconnectInterval: 600000 // 10 minutes }); logger.on('error', (error) => { console.log(error); }); logger.on('connect', () => { console.log('connected!'); }); ``` ## Logging Library Support ### log4js Use [log4js-fluent-appender](https://www.npmjs.com/package/log4js-fluent-appender). ### winston Before using [winston](https://github.com/winstonjs/winston) support, you should install it IN YOUR APPLICATION. ```js var winston = require('winston'); var config = { host: 'localhost', port: 24224, timeout: 3.0, requireAckResponse: true // Add this option to wait response from Fluentd certainly }; var fluentTransport = require('fluent-logger').support.winstonTransport(); var fluent = new fluentTransport('mytag', config); var logger = winston.createLogger({ transports: [fluent, new (winston.transports.Console)()] }); logger.on('flush', () => { console.log("flush"); }) logger.on('finish', () => { console.log("finish"); fluent.sender.end("end", {}, () => {}) }); logger.log('info', 'this log record is sent to fluent daemon'); logger.info('this log record is sent to fluent daemon'); logger.info('end of log message'); logger.end(); ``` **NOTE** If you use `winston@2`, you can use `fluent-logger@2.7.0` or earlier. If you use `winston@3`, you can use `fluent-logger@2.8` or later. ### stream Several libraries use stream as output. ```js 'use strict'; const Console = require('console').Console; var sender = require('fluent-logger').createFluentSender('tag_prefix', { host: 'localhost', port: 24224, timeout: 3.0, reconnectInterval: 600000 // 10 minutes }); var logger = new Console(sender.toStream('stdout'), sender.toStream('stderr')); logger.log('this log record is sent to fluent daemon'); setTimeout(()=> sender.end(), 5000); ``` ## Options **tag_prefix** The tag prefix string. You can specify `null` when you use `FluentSender` directly. In this case, you must specify `label` when you call `emit`. **host** The hostname. Default value = 'localhost'. See [socket.connect][1] **port** The port to listen to. Default value = 24224. See [socket.connect][1] **path** The path to your Unix Domain Socket. If you set `path` then fluent-logger ignores `host` and `port`. See [socket.connect][1] **timeout** Set the socket to timetout after `timeout` milliseconds of inactivity on the socket. See [socket.setTimeout][2] **reconnectInterval** Set the reconnect interval in milliseconds. If error occurs then reconnect after this interval. [1]: https://nodejs.org/api/net.html#net_socket_connect_path_connectlistener [2]: https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback **requireAckResponse** Change the protocol to at-least-once. The logger waits the ack from destination. **ackResponseTimeout** This option is used when requireAckResponse is true. The default is 190. This default value is based on popular `tcp_syn_retries`. **eventMode** Set [Event Modes](https://github.com/fluent/fluentd/wiki/Forward-Protocol-Specification-v1#event-modes). This logger supports `Message`, `PackedForward` and `CompressedPackedForward`. Default is `Message`. NOTE: We will change default to `PackedForward` and drop `Message` in next major release. **flushInterval** Set flush interval in milliseconds. This option has no effect in `Message` mode. The logger stores emitted events in buffer and flush events for each interval. Default `100`. **messageQueueSizeLimit** Maximum number of messages that can be in queue at the same time. If a new message is received and it overflows the queue then the oldest message will be removed before adding the new item. This option has effect only in `Message` mode. No limit by default. **security.clientHostname** Set hostname of this logger. Use this value for hostname based authentication. **security.sharedKey** Shared key between client and server. **security.username** Set username for user based authentication. Default values is empty string. **security.password** Set password for user based authentication. Default values is empty string. **sendQueueSizeLimit** Queue size limit in bytes. This option has no effect in `Message` mode. Default is `8 MiB`. **tls** Enable TLS for socket. **tlsOptions** Options to pass to tls.connect when tls is true. For more details, see following documents * [tls.connect()](https://nodejs.org/api/tls.html#tls_tls_connect_options_callback) * [tls.createSecureContext()](https://nodejs.org/api/tls.html#tls_tls_createsecurecontext_options) **internalLogger** Set internal logger object for FluentLogger. Use `console` by default. This logger requires `info` and `error` method. ## Examples ### Winston Integration An example of integrating with Winston can be found at [`./example/winston`](./example/winston). You will need Docker Compose to run it. After navigating to `./example/winston`, run `docker-compose up` and then `node index.js`. You should see the Docker logs having an `"it works"` message being output to FluentD. ## License Apache License, Version 2.0. [fluent-logger-python]: https://github.com/fluent/fluent-logger-python ## About NodeJS versions This package is compatible with NodeJS versions >= 6.

	Stars	Issues	Version	Updated	Created
fluent-logger	258	22	3.4.1	4 years ago	13 years ago
log4javascript	8	2	1.4.16	3 years ago	8 years ago
logging	54	6	3.3.0	3 years ago	13 years ago
morgan	7,827	25	1.10.0	4 years ago	10 years ago
pino	13,338	99	9.1.0	3 days ago	8 years ago
winston	22,116	504	3.13.0	2 months ago	13 years ago

fluent-logger vs log4javascript vs logging vs morgan vs pino vs winston

Downloads in past1 Month3 Months6 Months1 Year2 Years5 YearsAll time

Stats

Popular Searches

Sick of boring JavaScript newsletters?

Downloads in past