@trasherdk/posix-syslog

POSIX syslog bindings for Node.js — based on code from node-posix.

• Extracted from a fork node-posix

Provides openlog, closelog, syslog, setlogmask, and createLogger as a native C++ addon using N-API, with full TypeScript types and ESM support.

Installation

npm install @trasherdk/posix-syslog

Usage

import { openlog, syslog, closelog } from "@trasherdk/posix-syslog";

openlog("myprog", { pid: true, ndelay: true }, "local7");
syslog("info", "hello, world!");
closelog();

Multiple facilities

Use createLogger() to direct messages to different syslog facilities within the same process. Call openlog() once to set identity and options, then create loggers for each facility:

import { openlog, createLogger, closelog } from "@trasherdk/posix-syslog";

openlog("myapp", { pid: true, ndelay: true }, "user");

const auth = createLogger("auth");
const app  = createLogger("local0");

auth.info("login successful");
app.warning("disk usage high");
app.debug("processing request #42");

closelog();

API

openlog(identity, options, facility)

Open a connection to the logger.

• identity — name of the process visible in logged entries.
• options — object with boolean flags:
  • cons — Log to the system console on error.
  • ndelay — Connect to syslog daemon immediately.
  • nowait — Do not wait for child processes.
  • odelay — Delay open until syslog() is called.
  • pid — Log the process ID with each message.
• facility — facility code string: kern, user, mail, news, uucp, daemon, auth, authpriv, cron, ftp, lpr, syslog, local0..local7

Only user and local0..local7 are defined in the POSIX standard.

closelog()

Close connection to the logger.

setlogmask(mask)

Sets a priority mask for log messages. Further syslog() calls are only sent if their priority is included in the mask. Returns an object with boolean flags indicating which priorities were previously enabled.

setlogmask({ emerg: true, alert: true, crit: true });

syslog(priority, message)

Send a message to the syslog logger.

Priorities: emerg, alert, crit, err, warning, notice, info, debug

syslog("info", "hello, world!");

createLogger(facility)

Create a logger bound to a specific facility. The facility is OR'd into the priority on each call, overriding the default set by openlog().

Returns an object with a method for each priority level: emerg, alert, crit, err, warning, notice, info, debug

const log = createLogger("auth");
log.info("user logged in");

TypeScript

All exports are fully typed. Key types:

import type {
  SyslogPriority, SyslogFacility, SyslogOptions, SyslogMask, Logger,
} from "@trasherdk/posix-syslog";

License

MIT — Copyright (c) 2011-2015 Mika Eloranta