TAIL TALES

A TUI log viewer written in Rust

Objetives

To easy inspect existing logs or streaming logs, with some filters, marking of messages and easy finding information in the logs.

Use

• Can set default command or file to open: tt
• Can read exisitng files, checks for changes: tt /var/log/messages
• Can be used as pipe destination: journalctl -f | tt
• Can execute commands and show stdout / stderr: tt !journalctl -f -- AS bash does not like use of ! in commands there is an alternative format: tt -- journalctl -f. Another option is tt \!journalctl -f.

Commands

All keybindings are transalted to internal commands. It's possible to execute commands directly entering command mode (: by default).

Command	Description
quit	Exit the application
clear	Refresh the screen, usefull when its damaged because of non controlled ANSI characters
command	Opens command mode with a new command (not enough with mode command as that woudl not clear the current command)
exec	Executes a command, as wl-copy, xdg-open.. or any helper. With placeholders you can pass the original line or urlencoded
search_next	Search for the next occurrence
search_prev	Search for the previous occurrence
vmove	Move vertically, positive down, negative up
hmove	Move horizontally, positive right, negative left
vgoto	Goto to specific line number
clear_records	Clear all records
warning <msg...>	Display a warning message
toggle_mark	Toggle a mark on the current line. Its a data for the record with that color as mark, and will be used at render.
move_to_next_mark	Move to the next marked line
move_to_prev_mark	Move to the previous marked line
settings	Open the xdg program with the local settings file. If the file does not exist yet it is created with the default settings.
mode	Switch between different modes: normal, command, search or filter
toggle_details	Toggle the display of details

Keybindings

Key	Command
:	command
|	mode filter
f	mode filter
/	mode search
n	search_next
shift-n	search_prev
control-del	clear_records
control-l	refresh_screen
F1	exec xdg-open https://github.com/davidmoreno/tailtales/#use
F2	exec xdg-open https://www.perplexity.ai/search/new?q={{lineqs}}
F3	exec xdg-open https://www.duckduckgo.com/?q={{lineqs}}
F4	exec xdg-open https://google.com/search?q={{lineqs}}
q	quit
control-c	-- copy to clipboard --
up	vmove -1
k	vmove -1
page up	vmove -10
down	vmove 1
j	vmove 1
page down	vmove 10
left	hmove -1
control-left	hmove -10
right	hmove 1
control-right	hmove 10
home	vgoto 0
end	vgoto 2000000000
G	goto_line
space	toggle_mark yellow
1	toggle_mark red
2	toggle_mark green
3	toggle_mark blue
4	toggle_mark magenta
5	toggle_mark cyan
tab	move_to_next_mark
shift-back tab	move_to_prev_mark
esc	mode normal
v	toggle_details

Settings

It comes with some sensible default settings from the settings.yaml file. It can overwriten, by section at ~/.config/tailtales/settings.yaml or the appropiate XDG config directory. See the file for further information.

Rules

The settings file have several default rules, and more may be added (send your pull request with new file formats!).

It has a basic pattern on the file name to discover which rules to use and acording to the matrched rule it can set:

• Data extractors: as logfmt, patterns and regex. These extracted data allows easy filtering and search.
• Columns: From the extracted data, it can show some data into the columns.For example to easily format timestamp or processing time.
• Filters: Acording filters from the filtering language, allows to color the lines, or add a gutter (symbol at the left of the table).

Filter Language

Its possible to search and filter based on both the line and the structured parsed contents.

• Just text will look for text
• The proper way is "text", but if just a simple text is given its understood as text (converts the variable name to a string)
• ~ regex or better ~ "regex" can also be used to search / filter by regex
• Basic operations as >, <, >=, <=, ==, != between variablers (record fields) and strings or numbers

More will be added.

Example expressions

• INFO
• "^INFO -- The closing " is assumed
• timestamp <= "2025-01-01" -- The comparison is string based, so timestamps better in ISO format
• line_number > 1000 && line_number < 2000 -- TODO, no priority, no parenteheiss, will not work

Features

• TUI
• Read a log file and be able to navigate using arrows and simple search commands
• Read stdout/stderr from executed commands
• Filter messages with some simple expressions
• Parse the lines and provide a formated simple dictionary (key:value). Can see the log lines and the formatted data. Firswt version bassed on patterns.
• Logfmt format parsing
• Pattern format parsing
• Regex format parsing
• Filtering language
• Filtering and marking based on these filters
• Streaming input. Changes in the file, or pipe in, or executed command are seen inmediately.
• As it may have many many lines, be able to scroll efficiently
• Never blocking