R: Logging levels

loglevel {log4r} | R Documentation

## Logging levels

### Description

Functions for handling logging levels. With each log entry, a logging level is associated that indicate its severity – debugging output, informational output, warning message, error message or fatal error. Each logger only prints log entries where the log level is equal or above its threshold.

### Usage

    loglevel(i)

    is.loglevel(x, ...)

    as.loglevel(i)

    ## S3 method for class 'loglevel'
    print(x, ...)

    ## S3 method for class 'loglevel'
    as.numeric(x, ...)

    ## S3 method for class 'loglevel'
    as.character(x, ...)

    available.loglevels()

    verbosity(v)

### Arguments

`i` | An integer from the set 1..5. Otherwise it will be modified sensibly to fit in that range. Alternatively, a named logging level (one of "DEBUG", "INFO", "WARN", "ERROR", or "FATAL").
`x` | An object of class "loglevel"
`...` | Unused
`v` | A verbosity level from the set 5..1. For historical reasons, they do not match the log levels; a verbosity level of 1 corresponds to a logging level of 5, 2 corresponds to 4, etc.

### Details

To specify a logging level, use a character value, e.g. `"WARN"`, or an integer between 1 and 5. The function `available.levels` lists all possible logging levels.

### Value

An object of class "loglevel"

### Examples

    loglevel(2) == loglevel("INFO")
    loglevel("WARN") < loglevel("ERROR")
    loglevel(-1)
    try(loglevel("UNDEFINED"))
    is.loglevel("DEBUG")
    is.loglevel(loglevel("DEBUG"))
    as.numeric(loglevel("FATAL"))
    available.loglevels()

    ## Not run:
    library(optparse)
    library(log4r)

    optlist <- list(make_option(c('-v', '--verbosity-level'),
      type = "integer",
      dest = "verbosity",
      default = 1,
      help = "Verbosity threshold (5=DEBUG, 4=INFO 3=WARN, 2=ERROR, 1=FATAL)"))

    optparser <- OptionParser(option_list=optlist)
    opt <- parse_args(optparser)

    my.logger <- create.logger(logfile = "", level = verbosity(opt$verbosity))

    fatal(my.logger, "Fatal message")
    error(my.logger, "Error message")
    warn(my.logger, "Warning message")
    info(my.logger, "Informational message")
    debug(my.logger, "Debugging message")

    ## End(Not run)

[Package log4r version 0.4.2 Index]