syslog-protocol

SyslogProtocol.js

SyslogProtocol.js is a Syslog (RFC 3164) format parser that supports high-precision timestamps (RFC 3339, ISO 8601).

Given a Syslog message with a high-precision timestamp:

<38>1987-06-18T15:20:30.337Z server sshd[42]: Accepted publickey for user

It'll return the following object (with time being an instance of Date):

{ facility: "auth",
  facilityCode: 4,
  severity: "info",
  severityCode: 6,
  time: new Date("1987-06-18T15:20:30.337Z"),
  host: "server",
  process: "sshd",
  pid: 42,
  message: "Accepted publickey for user" }

Ironically, SyslogProtocol.js does not support plain RFC 3164's timestamps, which are in who-knows-what time zone and lack a year part. If you can, don't use them. If you're really keen on them, please let me know and I'll see about implementing.

Tour

• Supports RFC 3164 with high-precision timestamps (RFC 3339, ISO 8601).
  For example, Rsyslog's RSYSLOG_ForwardFormat uses those.
• Supports colon-less TAG/process identifiers/messages (which Heroku log drains send).
• Facility and severity names are <syslog.h> and syslog(3) compatible.
• All property names of the returned object have gone through serious sincere consideration and are amazingly well chosen.

Installing

npm install syslog-protocol

Using

Just require SyslogProtocol.js and use its parse function:

var SyslogProtocol = require("syslog-protocol")
var msg = "<38>1987-06-18T15:20:30.337Z server sshd[42]: Accepted publickey"
SyslogProtocol.parse(msg)

Alphanumeric process identifiers

SyslogProtocol.js can also handle alphanumeric process identifiers (sshd[foo]). For example, given Heroku's forwarded log:

<158>1987-06-18T15:20:30.337Z d.550e8400-e29b-41d4-a716-446655440000 heroku[router] at=info method=GET path=/

SyslogProtocol.js will return:

{ facility: "local3",
  facilityCode: 19,
  severity: "info",
  severityCode: 6,
  time: new Date("1987-06-18T15:20:30.337Z"),
  host: "d.550e8400-e29b-41d4-a716-446655440000",
  process: "heroku",
  pid: "router",
  message: "at=info method=GET path=/" }

Properties

The returned object from parse has the following properties:

Property	Description
facility	Facility name. See below for a full list of facilities.
facilityCode	Facility numeric code.
severity	Severity name. See below for a full list of severities.
severityCode	Severity numeric code.
time	Date instance from the timestamp.
host	Hostname or IP address.
process	Process name.
pid	Process identifier (taken from brackets after process name). If the message lacks one, pid won't be set at all. If it looks like a number, it'll be cast to Number.
message	Rest of the message.

Facilities

Facility names returned by SyslogProtocol.js match <syslog.h> and syslog(3).

Code	Facility
0	kern
1	user
2	mail
3	daemon
4	auth
5	syslog
6	lpr
7	news
8	uucp
9	cron
10	authpriv
11	ftp
12	ntp
13	logaudit
14	logalert
15	clock
16	local0
17	local1
18	local2
19	local3
20	local4
21	local5
22	local6
23	local7

Severities

Severity names returned by SyslogProtocol.js match <syslog.h> and syslog(3).
Blame them for the inconsistent naming.

Code	Severity
0	emerg
1	alert
2	crit
3	err
4	warning
5	notice
6	info
7	debug

License

SyslogProtocol.js is released under a Lesser GNU Affero General Public License, which in summary means:

• You can use this program for no cost.
• You can use this program for both personal and commercial reasons.
• You do not have to share your own program's code which uses this program.
• You have to share modifications (e.g. bug-fixes) you've made to this program.

For more convoluted language, see the LICENSE file.

About

Andri Möll typed this and the code.
Monday Calendar supported the engineering work.

If you find SyslogProtocol.js needs improving, please don't hesitate to type to me now at [e-mail] or create an issue online.