lnav v0.8.2 released!


  • The timestamp format for JSON log files can be specified with the "timestamp-format" option in the "line-format" array.
  • Added "min-width", "max-width", "align", and "overflow" options to the "line-format" in format definitions for JSON log files. These options give you more control over how the displayed line looks.
  • Added a "hidden" option to log format values so that you can hide JSON log fields from being displayed if they are not in the line format.
  • Added a "rewriter" field to log format value definitions that is a command used to rewrite the field in the pretty-printed version of a log message. For example, the HTTP access log format will rewrite the status code field to include the textual version (e.g. 200 (OK)).
  • Log message fields can now be hidden using the :hide-fields" command or by setting the 'hidden' property in the log format. When hidden, the fields will be replaced with a yellow ellipsis when displayed. Hiding large fields that contain extra details can make the log easier to read. The 'x' hotkey can be used to quickly toggle whether these fields are displayed or not.
  • Added a ':mark' command to bookmark the top line in the current view.
  • Added an ':alt-msg' command that can be used to set the text to be displayed in the bottom right of the command line. This command is mostly intended for use by hotkey maps to set the help text.
  • In lnav scripts, the first row of a SQL query result will now be turned into local variables that can be referenced in other commands or queries. For example, the following script will print the number one:
    ;SELECT 1 as foobar
       :eval :echo ${foobar}
  • Added an 'lnav_view_stack' SQL table that gives access to the view stack.
  • Added a 'top_time' column to the lnav_views table so that you can get the timestamp for the top line in views that are time-based as well as allowing you to move the view to a given time with an UPDATE statement.
  • Added a 'search' column to the lnav_views table so that you can perform a text search programmatically.
  • Added a 'regexp_capture(, )' table-valued function for getting detailed results from matching a regular expression against a string.
  • Added a 'timediff(, )' SQL function for computing the difference between two relative or absolute timestamps.
  • Log formats can now define a default set of highlights with the "highlights" property.
  • Added a '|search-for ' built-in script that can be used to start a search from the command-line.
  • Log format definitions can now specify the expected log level for a sample line. This check should make it easier to validate the definition.

Interface Changes:

  • Command and SQL documentation is now displayed in a section at the bottom of the screen when a command or query is being entered. Some commands will also display a preview of the command results. For example, the ':open' command will display the first ten lines of the file to be opened and the ':filter-out' command will highlight text that matches in the current view. The preview pane can be shown/hidden by pressing CTRL-P.
  • The color used for text colored via ":highlight" is now based on the the regex instead of randomly picked so that colors are consistent across invocations.
  • The "graph" view has been removed since it's functionality has been obsoleted by other features, like ":create-search-table".
  • When doing a search, if a hit is found within a second after hitting , the view will move to the matched line. The previous behavior was to stay on the current line, which tended to be a surprise to new users.
  • Pressing 'n'/'N' to move through the next/previous search hit will now skip adjacent lines, up to the vertical size of the view. This should make scanning through clusters of hits much faster. Repeatedly pressing these keys within a short time will also accelerate scanning by moving the view at least a full page at a time.

Breaking Changes:

  • The captured timestamp text in log files must fully match a known format or an error will be reported. The previous behavior was to ignore any text at the end of the line.


  • You can now execute commands from the standard input by using a dash (-) with the '-f' command-line argument. Reading commands from a file descriptor should also work, for example, with the following bash syntax:

    $ lnav -f <(echo data-preserve-html-node="true" :open the-file-to-open)

  • Programming language syntax highlighting should now only be applied to source code files instead of everywhere.