quarto_log: Log debug information to a configurable file

In quarto-dev/quarto-r: R Interface to 'Quarto' Markdown Publishing System

Log debug information to a configurable file

Description

This function logs messages to a file only when in debug mode to help diagnose issues with Quarto vignettes in pkgdown and other contexts.

Usage

quarto_log(
  ...,
  file = NULL,
  append = TRUE,
  timestamp = TRUE,
  prefix = "DEBUG: "
)

Arguments

...	Messages to log (will be concatenated)
file	Path to log file. If NULL, uses get_log_file() to determine the file. Default will be ./quarto-r-debug.log if no configuration is found.
append	Logical. Should the messages be appended to the file? Default TRUE.
timestamp	Logical. Should a timestamp be added? Default TRUE.
prefix	Character. Prefix to add before each log entry. Default "DEBUG: ".

Details

Debug mode will be enabled automatically when debugging Github Actions workflows, or when Quarto CLI's environment variable QUARTO_LOG_LEVEL is set to DEBUG.

Value

Invisibly returns TRUE if logging occurred, FALSE otherwise

Configuration

Enable debugging messages:

• Set quarto.log.debug = TRUE (or R_QUARTO_LOG_DEBUG = TRUE environment variable)

Change log file path:

• Set quarto.log.file to change the file path (or R_QUARTO_LOG_FILE environment variable)

• Default will be ./quarto-r-debug.log

Automatic debug mode:

• Debug mode will be on automatically when debugging Github Actions workflows

• When Quarto CLI's environment variable QUARTO_LOG_LEVEL is set to DEBUG

Examples

## Not run: 
# Set log file via environment variable
Sys.setenv(R_QUARTO_LOG_FILE = "~/quarto-debug.log")

# Or via option
options(quarto.log.file = "~/quarto-debug.log")

# Enable debug mode
options(quarto.log.debug = TRUE)

# Log some information
quarto_log("Starting process")
quarto_log("R_LIBS:", Sys.getenv("R_LIBS"))
quarto_log(".libPaths():", paste0(.libPaths(), collapse = ":"))

## End(Not run)

quarto-dev/quarto-r documentation built on June 14, 2025, 3:45 a.m.