logger 0.4.1 (2025-09-08)

New features and quality of life improvements:

• Support renaming meta fields (#217, @atusy)
• Added log_elapsed() to show cumulative elapsed running time (#221, @thomasp85)
• log_errors() gains a traceback argument that toggles whether the error traceback should be logged along with the message (fix #86 via #223, @thomasp85)
• File and line location of the log call is now available to the layouts (fix #110 via #224, @thomasp85)
• New formatter_cli() allows you to use the syntax from the cli package to create log messages (fix #210 via #225, @thomasp85)
• New log_chunk_time() helper function to automatically log the execution time of knitr code chunks (fix #222 via #227, @thomasp85)
• Allow user to overwrite the timestamp during logging if needed (fix #230, @thomasp85)

logger 0.4.0 (2024-10-19)

A lot of internal code quality improvements and standardization,
improved documentations, modernized tests, performance speedups.

New features

• logo 😻 (#196, @hadley)
• computing metadata lazily, so various expensive computations are only performed if you actually add them to the log (#105, @hadley)
• log_appender(), log_layout() and log_formatter() now check that you are calling them with a function, and return the previously set value (#170, @hadley)
• new function to return number of log indices (#194, @WurmPeter)
• appender_async is now using mirai instead of a custom background process and queue system (#214, @hadley @shikokuchuo)
• layout_gha() for providing native GitHub Action logging. This automatically gets used when running code in github actions (@thomasp85)

Fixes

• eval scoping and lazy eval (#178, @hadley)

Housekeeping

• update pkgdown site to Bootstrap 5 and related revamp, e.g. reference index and run/show examples (#159 #165 #193, @hadley)
• roxygen updated to use markdown, general cleanup (#160 #161 #191 #201, @hadley)
• testing improvements, e.g. move to testthat v3 and snapshots, syntactic sugar (#163 #167 #168 #169 #171 #192, @hadley)
• README tweaks (#162 #176, @hadley)
• modernize GitHub Actions (#171, @hadley)
• drop support for R versions below 4.0.0 (#177, @hadley)
• internal function tweaks (#181 #187 #197, @hadley)
• restyle sources (#185 #186 #191 #199, @daroczig and @hadley)

logger 0.2.2 (2021-10-10)

Maintenance release:

• fix unbalanced code chunk delimiters in vignette (yihui/knitr#2057)

logger 0.2.1 (2021-07-06)

Maintenance release:

• update appender_slack to use slackr_msg instead of text_slackr

logger 0.2.0 (2021-03-03)

Breaking changes

• appender_console writes to stderr by default instead of stdout (#28)

Fixes

• default date format in glue layouts (#44, @burgikukac)
• fn reference in loggers will not to a Cartesian join on the log lines and message, but merge (and clean up) the fn even for large anonymous functions (#20)

New features

• allow defining the log level threshold as a string (#13, @artemklevtsov)
• allow updating the log level threshold, formatter, layout and appender in all namespaces with a single call (#50)
• new argument to appender_file to optionally truncate before appending (#24, @eddelbuettel)
• new arguments to appender_file to optionally rotate the log files after appending (#42)
• new meta variables for logging in custom layouts: R version and calling package's version
• improved performance by not evaluating arguments when the log record does not meet the log level threshold (#27, @jozefhajnala)
• logger in now part of the Mikata Project: https://mikata.dev

New helper functions

• %except%: evaluate an expression with fallback
• log_separator: logging with separator lines (#16)
• log_tictoc: tic-toc logging (#16, @nfultz)
• log_failure: log error before failing (#19, @amy17519)
• log_messages, log_warnings, log_errors: optionally auto-log messages, warnings and errors using globalCallingHandlers on R 4.0.0 and above, and injecting logger calls to message, warnings and stop below R 4.0.0
• log_shiny_input_changes: auto-log input changes in Shiny apps (#25)

New formatter functions

• layout_pander: transform R objects into markdown before logging (#22)

New layout functions

• layout_blank: blank log messages without any modification
• layout_json_parser: render the layout as a JSON blob after merging with requested meta fields

New appender functions

• appender_telegram: deliver log records to Telegram (#14, @artemklevtsov)
• appender_syslog: deliver log records to syslog (#30, @atheriel)
• appender_kinesis: deliver log records to Amazon Kinesis (#35)
• appender_async: wrapper function for other appender functions to deliver log records in a background process asynchronously without blocking the master process (#35)

logger 0.3.0 (2024-03-03)

Many unrelated small features, fixes and documentation updates collected over 2+ years.

New features

• update log_* functions to invisibly return the formatted log message and record (#26, @r2evans)
• add namespace argument to log_shiny_input_changes (#93, @kpagacz)
• optionally suppress messages in globalCallingHandlers after being logged (#100, @DanChaltiel)
• as.loglevel helper to convert string/number to loglevel (requested by @tentacles-from-outer-space)
• new formatter function: formatter_glue_safe (#126, @terashim)
• support OFF log level (#138, @pawelru)
• override default INFO log level via env var (#145, requested by sellorm)

Fixes

• handle zero-length messages in formatter_glue_or_sprintf (#74, @deeenes)
• generalize log_separator to work with all layout functions (#96, @Polkas)
• support log levels in log_shiny_input_changes (#103, @taekeharkema)
• fix fn name lookup/reference with nested calls (#120, reported by @averissimo)
• force the file argument of appender_tee (#124, reported by @dbontemps)
• don't allow stacking logger hooks on messages/warnings/errors (reported by @jkeuskamp)
• improve fragile test case when Hmisc loaded (#131, @r2evans)
• pass index, namespace etc from log_ functions down to log_level (#143, @MichaelChirico)
• refer to the caller function in global message logger hooks (#146, reported by @gabesolomon10)

logger 0.1 (2018-12-20)

Initial CRAN release after collecting feedback for a month on Twitter at https://twitter.com/daroczig/status/1067461632677330944:

• finalized design of a log request defined by

  • a log level threshold,
  • a formatter function preparing the log message,
  • a layout function rendering the actual log records and
  • an appender function delivering to the log destination

• detailed documentation with 7 vignettes and a lot of examples, even some benchmarks

• ~75% code coverage for unit tests

• 5 formatter functions mostly using paste, sprintf and glue

• 6 layout functions with convenient wrappers to let users define custom layouts via glue or JSON, including colorized output

• 5 appender functions delivering log records to the console, files, Pushbullet and Slack

• helper function to evaluate an expressions with auto-logging both the expression and its result

• helper function to temporarily update the log level threshold

• helper function to skip running the formatter function on a log message

• mostly backward compatibly with the logging and futile.logger packages