Vicious
-------
Vicious is a modular widget library for window managers, but mostly
catering to users of the "awesome" window manager. It was derived from
the old "Wicked" widget library, and has some of the old Wicked widget
types, a few of them rewritten, and a good number of new ones:

  - http://git.sysphere.org/vicious/about/

Vicious widget types are a framework for creating your own
widgets. Vicious contains modules that gather data about your system,
and a few "awesome" helper functions that make it easier to register
timers, suspend widgets and so on.

For now Vicious doesn't depend on any third party Lua libraries, to
make it easier to install and use. That means some system utilities
are used instead, where available:

  - hddtemp        for the HDD Temperature widget type
  - alsa-utils     for the Volume widget type
  - wireless_tools for the Wireless widget type
  - curl           for widget types accessing network resources


Usage
-----
When provided by an operating system package, or installed from source
into the Lua library path Vicious can be used as a regular Lua
library, to be used stand-alone or to feed widgets of any window
manager (ie. Ion, WMII). It is compatible with both Lua v5.1 and v5.2.

  $ lua
   > widgets = require("vicious.widgets")
   > print(widgets.volume(nil, "Master")[1])
     100


Usage within Awesome
--------------------
To use Vicious with Awesome, install the package from your operating
system provider, or download the source code and move it to your
awesome configuration directory in $XDG_CONFIG_HOME (usually ~/.config):

  $ mv vicious $XDG_CONFIG_HOME/awesome/

Vicious will only load modules for widget types you intend to use in
your awesome configuration, to avoid having useless modules sitting in
your memory.

Then add the following to the top of your rc.lua:

  vicious = require("vicious")

Once you create a widget (a textbox, graph or a progressbar) call
vicious.register() to register it with Vicious:

  vicious.register(widget, wtype, format, interval, warg)

    widget
      - widget created with widget() or awful.widget() (in case of a
        graph or a progressbar)

    wtype
      - widget type or a function
        - any of the available (default, or custom) widget types can
          be used here, see below for a list of those provided by
          Vicious
      - function
        - custom functions from your own "awesome" configuration can
          be registered as widget types, see the "Custom widget types"
          section

    format
      - string argument or a function
        - $1, $2, $3... will be replaced by their respective value
          returned by the widget type, some widget types return tables
          with string keys, in that case use: ${key}
      - function
        - function(widget, args) can be used to manipulate data
          returned by the widget type, more about this below

    interval
      - number of seconds between updates of the widget, 2s by
        default, also read the "Power" section below

    warg
      - some widget types require an argument to be passed, for example
        the battery ID


Other functions
---------------
Unregister a widget:
  vicious.unregister(widget, keep)

    - if keep is true widget will be suspended, waiting to be
      activated

Suspend all widgets:
  vicious.suspend()

    - example automation script for the "laptop-mode-tools" start-stop
      module: http://sysphere.org/~anrxc/local/sources/lmt-vicious.sh

Restart suspended widgets:
  vicious.activate(widget)

    - if widget is provided only that widget will be activated

Enable caching of a widget type:
  vicious.cache(wtype)

    - enable caching of values returned by a widget type

Force update of widgets:
  vicious.force({ widget, })

    - widget argument is a table with one or more widgets that will be
      updated


Widget types
------------
Widget types consist of worker functions that take the "format"
argument given to vicious.register as the first argument, "warg" as
the second, and return a table of values to insert in the format
string.

vicious.widgets.cpu
  - provides CPU usage for all available CPUs/cores
  - returns 1st value as usage of all CPUs/cores, 2nd as usage of
    first CPU/core, 3rd as usage of second CPU/core etc.

vicious.widgets.cpuinf
  - provides speed and cache information for all available CPUs/cores
  - returns a table with string keys, using CPU ID as a base:
    {cpu0 mhz}, {cpu0 ghz}, {cpu0 kb}, {cpu0 mb}, {cpu1 mhz} etc.

vicious.widgets.cpufreq
  - provides freq, voltage and governor info for a requested CPU
  - takes the CPU ID as an argument, i.e. "cpu0"
  - returns 1st value as frequency of requested CPU in MHz, 2nd in
    GHz, 3rd as voltage in mV, 4th as voltage in V and 5th as the
    governor state

vicious.widgets.thermal
  - provides temperature levels of ACPI and coretemp thermal zones
  - takes the thermal zone as an argument, i.e. "thermal_zone0", or a
    table with 1st field as thermal zone, 2nd as data source -
    available data sources are "proc", "core" and "sys" (which is the
    default when only the zone is provided) and 3rd optional argument
    as a temperature input file to read
  - returns 1st value as temperature of requested thermal zone

vicious.widgets.uptime
  - provides system uptime and load information
  - returns 1st value as uptime in days, 2nd as uptime in hours, 3rd
    as uptime in minutes, 4th as load average for past 1 minute, 5th
    for 5 minutes and 6th for 15 minutes

vicious.widgets.bat
  - provides state, charge, remaining time and wear for a requested
    battery
  - takes battery ID as an argument, i.e. "BAT0"
  - returns 1st value as state of requested battery, 2nd as charge
    level in percent, 3rd as remaining (charging or discharging)
    time and 4th as the wear level in percent

vicious.widgets.mem
  - provides RAM and Swap usage statistics
  - returns 1st value as memory usage in percent, 2nd as memory usage,
    3rd as total system memory, 4th as free memory, 5th as swap usage
    in percent, 6th as swap usage, 7th as total system swap, 8th as
    free swap and 9th as memory usage with buffers and cache

vicious.widgets.os
  - provides operating system information
  - returns 1st value as the operating system in use, 2nd as the
    release version, 3rd as your username, 4th the hostname, 5th as
    available system entropy and 6th value as available entropy in
    percent

vicious.widgets.fs
  - provides file system disk space usage
  - takes an (optional) argument which, if true, includes remote file
    systems, only local file systems are included by default
  - returns a table with string keys, using mount points as a base:
    {/ size_mb}, {/ size_gb}, {/ used_mb}, {/ used_gb}, {/ used_p},
    {/ avail_mb}, {/ avail_gb}, {/ avail_p}, {/home size_mb} etc.

vicious.widgets.dio
  - provides I/O statistics for all available storage devices
  - returns a table with string keys: {sda total_s}, {sda total_kb},
    {sda total_mb}, {sda read_s}, {sda read_kb}, {sda read_mb},
    {sda write_s}, {sda write_kb}, {sda write_mb}, {sdb1 total_s} etc.

vicious.widgets.raid
  - provides state information for a requested RAID array
  - takes the RAID array ID as an argument
  - returns 1st value as the number of assigned, and 2nd as active,
    devices in the array

vicious.widgets.hddtemp
  - provides hard drive temperatures using the hddtemp daemon
  - takes the hddtemp listening port as an argument, or defaults to
    port 7634
  - returns a table with string keys, using hard drives as a base:
    {/dev/sda} and {/dev/sdc} for example

vicious.widgets.net
  - provides state and usage statistics of all network interfaces
  - returns a table with string keys, using net interfaces as a base:
    {eth0 carrier}, {eth0 rx_b}, {eth0 tx_b}, {eth0 rx_kb}, {eth0 tx_kb},
    {eth0 rx_mb}, {eth0 tx_mb}, {eth0 rx_gb}, {eth0 tx_gb}, {eth0 down_b},
    {eth0 up_b}, {eth0 down_kb}, {eth0 up_kb}, {eth0 down_mb},
    {eth0 up_mb}, {eth0 down_gb}, {eth0 up_gb}, {eth1 rx_b} etc.

vicious.widgets.wifi
  - provides wireless information for a requested interface
  - takes the network interface as an argument, i.e. "wlan0"
  - returns a table with string keys: {ssid}, {mode}, {chan}, {rate},
    {link}, {linp} (link quality in percent) and {sign} (signal level)

vicious.widgets.mbox
  - provides the subject of last e-mail in a mbox file
  - takes the full path to the mbox as an argument, or a table with
    1st field as path, 2nd as maximum length and 3rd (optional) as
    widget name - if 3rd field is present scrolling will be used (note: the
    path will be escaped so special variables like ~ will not work, use
    os.getenv("HOME").."mail" instead to access environment variables)
  - returns 1st value as the subject of the last e-mail

vicious.widgets.mboxc
  - provides the count of total, old and new messages in mbox files
  - takes a table with full paths to mbox files as an argument
  - returns 1st value as the total count of messages, 2nd as the count
    of old messages and 3rd as the count of new messages

vicious.widgets.mdir
  - provides the number of new and unread messages in Maildir
    structures/directories
  - takes a table with full paths to Maildir structures as an argument
  - returns 1st value as the count of new messages and 2nd as the
    count of "old" messages lacking the Seen flag

vicious.widgets.gmail
  - provides count of new and subject of last e-mail on Gmail
  - takes an (optional) argument, if it's a number subject will be
    truncated, if a table, with 1st field as maximum length and 2nd
    the widget name (i.e. "gmailwidget"), scrolling will be used
  - keeps login information in the ~/.netrc file, example:
    machine mail.google.com login user password pass
  - returns a table with string keys: {count} and {subject}
  - to be able to use this widget, make sure in your Gmail account
    you disabled "two step verification" (https://support.google.com/accounts/answer/1064203)
    and then "allowed access to your account for less secure apps" (https://www.google.com/settings/security/lesssecureapps)

vicious.widgets.org
  - provides agenda statistics for Emacs org-mode
  - takes a table with full paths to agenda files, that will be
    parsed, as an argument
  - returns 1st value as count of tasks you forgot to do, 2nd as count
    of tasks for today, 3rd as count of tasks for the next 3 days and
    4th as count of tasks to do in the week

vicious.widgets.pkg
  - provides number of pending updates on UNIX systems
  - takes the distribution name as an argument, i.e. "Arch"
  - returns 1st value as the count of available updates

vicious.widgets.mpd
  - provides Music Player Daemon information
  - takes a table as an argument, 1st field should be the password (or
    nil), 2nd the hostname (or nil) and 3rd port (or nil) - if no
    argument is provided connection attempt will be made to localhost
    port 6600 with no password
  - returns a table with string keys: {volume}, {state}, {Artist},
    {Title}, {Album}, {Genre} and optionally {Name} and {file}

vicious.widgets.volume
  - provides volume levels and state of requested ALSA mixers
  - takes the ALSA mixer control as an argument, i.e. "Master",
    optionally append the card ID or other options, i.e. "PCM -c 0"
  - returns 1st value as the volume level and 2nd as the mute state of
    the requested channel

vicious.widgets.weather
  - provides weather information for a requested station
  - takes the ICAO station code as an argument, i.e. "LDRI"
  - returns a table with string keys: {city}, {wind}, {windmph},
    {windkmh}, {sky}, {weather}, {tempf}, {tempc}, {humid}, {dewf},
    {dewc}, {press}

vicious.widgets.date
  - provides access to os.date, with optional time formatting provided
    as the format string - using regular date sequences
  - takes optional time offset, in seconds, as an argument for example
    to calculate time zone differences, otherwise current time is
    formatted
  - returns the output of os.date, formatted by provided sequences


Custom widget types
-------------------
Use any of the existing widget types as a starting point for your
own. Write a quick worker function that does the work and plug it
in. How data will be formatted, will it be red or blue, should be
defined in rc.lua (or somewhere else, outside the actual module).

Before writing a widget type you should check if there is already one
in the contrib directory of Vicious. The contrib directory contains
extra widgets you can use. Some are for less common hardware, and
other were contributed by Vicious users. The contrib directory also
holds widget types that were obsoleted or rewritten. Contrib widgets
will not be imported by init unless you explicitly enable it, or load
them in your rc.lua.

Rudi Siegel, a FreeBSD user, published his FreeBSD branch. If you are
also a BSD user you can find his work here:

  - https://bitbucket.org/mutluyum/vicious_bsd/

Some users would like to avoid writing new modules. For them Vicious
kept the old Wicked functionality, possibility to register their own
functions as widget types. By providing them as the second argument to
vicious.register. Your function can accept "format" and "warg"
arguments, just like workers.


Power and Caching
-----------------
When a lot of widgets are in use they, and awesome, can generate a lot
of wake-ups and also be very expensive for system resources. This is
especially important when running on battery power. It was a big
problem with awesome v2 and widgets that used shell scripts to gather
data, and with widget libraries written in languages like Ruby.

Lua is an extremely fast and efficient programming language, and
Vicious takes advantage of that. But suspending Vicious widgets is one
way to prevent them from draining your battery, despite that.

Update intervals also play a big role, and you can save a lot of power
with a smart approach. Don't use intervals like: 5, 10, 30, 60... to
avoid harmonics. If you take the 60-second mark as an example, all of
your widgets would be executed at that point. Instead think about
using only prime numbers, in that case you will have only a few
widgets executed at any given time interval. When choosing intervals
also consider what a widget actually does. Some widget types read
files that reside in memory, others call external utilities and some,
like the mbox widget, read big files.

Vicious can also cache values returned by widget types. Caching
enables you to have multiple widgets using the same widget type. With
caching its worker function gets executed only once - which is also
great for saving power.

  - Some widget types keep internal data and if you call one multiple
    times without caching, the widget that executes it first would
    modify stored values. This can lead to problems and give you
    inconsistent data. Remember it for widget types like CPU and
    Network usage, which compare the old set of data with the new one
    to calculate current usage.

  - Widget types that require a widget argument to be passed should be
    handled carefully. If you are requesting information for different
    devices then caching should not be used, because you could get
    inconsistent data.


Security
--------
At the moment only one widget type (Gmail) requires auth. information
in order to get to the data. In the future there could be more, and
you should give some thought to the issue of protecting your data. The
Gmail widget type by default stores login information in the ~/.netrc
file, and you are advised to make sure that file is only readable by
the owner. Other than that we can not force all users to conform to
one standard, one way of keeping it secure, like in some keyring.

First let's clear why we simply don't encrypt the login information
and store it in ciphertext. By exposing the algorithm anyone can
reverse the encryption steps. Some claim even that's better than
plaintext but it's just security trough obscurity.

Here are some ideas actually worth your time. Users that have KDE (or
parts of it) installed could store their login information into the
Kwallet service and request it via DBus from the widget type. It can
be done with tools like "dbus-send" and "qdbus". The Gnome keyring
should support the same, so those with parts of Gnome installed could
use that keyring.

Users of GnuPG (and its agent) could consider encrypting the netrc
file with their GPG key. Trough the GPG Passphrase Agent they could
then decrypt the file transparently while their session is active.


Usage examples
---------------------------------
Start with a simple widget, like date. Then build your setup from
there, one widget at a time. Also remember that besides creating and
registering widgets you have to add them to a wibox (statusbar) in
order to actually display them.

Date widget
  datewidget = wibox.widget.textbox()
  vicious.register(datewidget, vicious.widgets.date, "%b %d, %R")

  - updated every 2 seconds (the default interval), uses standard
    date sequences as the format string

Memory widget
  memwidget = wibox.widget.textbox()
  vicious.cache(vicious.widgets.mem)
  vicious.register(memwidget, vicious.widgets.mem, "$1 ($2MB/$3MB)", 13)

  - updated every 13 seconds, appends "MB" to 2nd and 3rd returned
    values and enables caching of this widget type

HDD temperature widget
  hddtempwidget = wibox.widget.textbox()
  vicious.register(hddtempwidget, vicious.widgets.hddtemp, "${/dev/sda} °C", 19)

  - updated every 19 seconds, requests the temperature level of the
    {/dev/sda} key/disk and appends "°C" to the returned value, does
    not provide the port argument so default port is used

Mbox widget
  mboxwidget = wibox.widget.textbox()
  vicious.register(mboxwidget, vicious.widgets.mbox, "$1", 5, "/home/user/mail/Inbox")

  - updated every 5 seconds, provides full path to the mbox as an
    argument

Battery widget
  batwidget = awful.widget.progressbar()
  batwidget:set_width(8)
  batwidget:set_height(10)
  batwidget:set_vertical(true)
  batwidget:set_background_color("#494B4F")
  batwidget:set_border_color(nil)
  batwidget:set_color({ type = "linear", from = { 0, 0 }, to = { 0, 10 },
      stops = { { 0, "#AECF96" }, { 0.5, "#88A175" }, { 1, "#FF5656" }})
  vicious.register(batwidget, vicious.widgets.bat, "$2", 61, "BAT0")

  - updated every 61 seconds, requests the current battery charge
    level and displays a progressbar, provides "BAT0" battery ID as an
    argument

CPU usage widget
  cpuwidget = awful.widget.graph()
  cpuwidget:set_width(50)
  cpuwidget:set_background_color("#494B4F")
  cpuwidget:set_color({ type = "linear", from = { 0, 0 }, to = { 50, 0 },
      stops = { { 0, "#FF5656" }, { 0.5, "#88A175" }, { 1, "#AECF96" }})
  vicious.cache(vicious.widgets.cpu)
  vicious.register(cpuwidget, vicious.widgets.cpu, "$1", 3)

  - updated every 3 seconds, feeds the graph with total usage
    percentage of all CPUs/cores and enable caching of this widget
    type


Format functions
----------------
You can use a function instead of a string as the format parameter.
Then you are able to check the value returned by the widget type and
change it or perform some action. You can change the color of the
battery widget when it goes below a certain point, hide widgets when
they return a certain value or maybe use string.format for padding.

  - Do not confuse this with just coloring the widget, in those cases
    standard pango markup can be inserted into the format string.

The format function will get the widget as its first argument, table
with the values otherwise inserted into the format string as its
second argument, and will return the text/data to be used for the
widget.

Example
  mpdwidget = wibox.widget.textbox()
  vicious.register(mpdwidget, vicious.widgets.mpd,
    function (widget, args)
      if   args["{state}"] == "Stop" then return ""
      else return '<span color="white">MPD:</span> '..
             args["{Artist}"]..' - '.. args["{Title}"]
      end
    end)

  - hides the mpd widget when no song is playing, updated every 2
    seconds (the default interval)

Example
  uptimewidget = wibox.widget.textbox()
  vicious.register(uptimewidget, vicious.widgets.uptime,
    function (widget, args)
      return string.format("Uptime: %2dd %02d:%02d ", args[1], args[2], args[3])
    end, 61)

  - uses string.format for padding uptime values to a minimum amount
    of digits, updated every 61 seconds

When it comes to padding it is also useful to mention how a widget can
be configured to have a fixed width. You can set a fixed width on your
textbox widgets by changing their .width field (by default width is
automatically adapted to text width).

Example
  uptimewidget = wibox.widget.textbox()
  uptimewidget:set_align("right")
  vicious.register(uptimewidget, vicious.widgets.uptime, "$1 $2:$3", 61)
  uptimewidget = wibox.layout.constraint(uptimewidget, "exact", 50, nil)

  - forces a fixed width of 50px to the uptime widget, and aligns its
    text to the right

Another use case are stacked graphs (aka multigraphs) which Vicious
does not handle on its own at the moment, as it's hard to pass on
color index arguments elegantly. But they are not unusable, far from
it.

Example
  ctext = wibox.widget.textbox()
  cgraph = awful.widget.graph()
  cgraph:set_width(100):set_height(20)
  cgraph:set_stack(true):set_max_value(100)
  cgraph:set_background_color("#494B4F")
  cgraph:set_stack_colors({ "#FF5656", "#88A175", "#AECF96" })
  vicious.register(ctext, vicious.widgets.cpu,
    function (widget, args)
      cgraph:add_value(args[2], 1) -- Core 1, color 1
      cgraph:add_value(args[3], 2) -- Core 2, color 2
      cgraph:add_value(args[4], 3) -- Core 3, color 3
    end, 3)

  - enables graph stacking/multigraph and plots usage of all three CPU
    cores on a single graph, the textbox "ctext" is just an empty
    placeholder, graph is updated every 3 seconds

A lot of users are not happy with default symbols used in volume,
battery, cpufreq and other widget types. You can use your own symbols
without any need to modify modules.

  volumewidget = wibox.widget.textbox()
  vicious.register(volumewidget, vicious.widgets.volume,
    function(widget, args)
      local label = { ["♫"] = "O", ["♩"] = "M" }
      return "Volume: " .. args[1] .. "% State: " .. label[args[2]]
    end, 2, "PCM")

  - uses a custom table map to modify symbols representing the mixer
    state; on or off/mute


Other
-----
Read "awesome" manual pages:

  - awesome(1)  awesomerc(5)

Awesome widgets explained:

  - http://awesome.naquadah.org/wiki/Widgets_in_awesome

Example "awesome" configuration:

  - http://git.sysphere.org/awesome-configs/


Authors
-------
Wicked written by:
  - Lucas de Vries           <lucas glacicle.com>

Vicious written by:
  - Adrian C. (anrxc)        <anrxc sysphere.org>

Vicious major contributors:
  - Benedikt Sauer           <filmor gmail.com>
  - Greg D.                  <jabbas jabbas.pl>
  - Henning Glawe            <glaweh debian.org>
  - Rémy C.                  <shikamaru mandriva.org>
  - Hiltjo Posthuma          <hiltjo codemadness.org>
  - Hagen Schink             <troja84 googlemail.com>
  - Jörg Thalheim            <jthalheim gmail.com>
  - Arvydas Sidorenko        <asido4 gmail.com>
  - Dodo The Last            <dodo.the.last gmail.com>
  - ...
  - Consult git log for a complete list of contributors