AppenderSyslog: Log to the POSIX system log

In lgrExtra: Extra Appenders for 'lgr'

Log to the POSIX system log

Description

An Appender that writes to the syslog on supported POSIX platforms. Requires the rsyslog package.

Value

The ⁠$new()⁠ method returns an R6::R6 that inherits from lgr::Appender and can be uses as an appender by a lgr::Logger.

Super classes

lgr::Filterable -> lgr::Appender -> AppenderSyslog

Public fields

syslog_levels.

Either a named character vector or a function mapping lgr lgr::log_levels to rsyslog log levels. See ⁠$set_syslog_levels()⁠.

Active bindings

identifier

character scalar. A string identifying the process; if NULL defaults to the logger name

syslog_levels.

Either a named character vector or a function mapping lgr lgr::log_levels to rsyslog log levels. See ⁠$set_syslog_levels()⁠.

Methods

Public methods

• AppenderSyslog$new()

• AppenderSyslog$append()

• AppenderSyslog$set_syslog_levels()

• AppenderSyslog$set_identifier()

Inherited methods

• lgr::Filterable$add_filter()
• lgr::Filterable$filter()
• lgr::Filterable$remove_filter()
• lgr::Filterable$set_filters()
• lgr::Appender$format()
• lgr::Appender$set_layout()
• lgr::Appender$set_threshold()

---

Method new()

Usage

AppenderSyslog$new(
  identifier = NULL,
  threshold = NA_integer_,
  layout = LayoutFormat$new("%m"),
  filters = NULL,
  syslog_levels = c(CRITICAL = "fatal", ERR = "error", WARNING = "warn", INFO = "info",
    DEBUG = "debug", DEBUG = "trace")
)

---

Method append()

Usage

AppenderSyslog$append(event)

---

Method set_syslog_levels()

Define conversion between lgr and syslog log levels

Usage

AppenderSyslog$set_syslog_levels(x)

Arguments

x

• a named character vector mapping whose names are log levels as understood by rsyslog::syslog() and whose values are lgr log levels (either character or numeric)

• a function that takes a vector of lgr log levels as input and returns a character vector of log levels for rsyslog::syslog().

---

Method set_identifier()

Set a string to identify the process.

Usage

AppenderSyslog$set_identifier(x)

See Also

lgr::LayoutFormat, lgr::LayoutGlue

Other Appenders: AppenderAWSCloudWatchLog, AppenderDbi, AppenderDynatrace, AppenderElasticSearch, AppenderGmail, AppenderPool, AppenderPushbullet, AppenderSendmail

Examples

if (requireNamespace("rsyslog", quietly = TRUE) && Sys.info()[["sysname"]] == "Linux") {
  lg <- lgr::get_logger("rsyslog/test")
  lg$add_appender(AppenderSyslog$new(), "syslog")
  lg$info("A test message")
  print(system("journalctl -t 'rsyslog/test'"))

  invisible(lg$config(NULL))  # cleanup
}

lgrExtra documentation built on Nov. 5, 2025, 7:13 p.m.