contrib/statusd/statusd_mpd.lua

   1 -- Authors: <delirium@hackish.org>
   2 -- License: Unknown
   3 -- Last Changed: Unknown
   4 --
   5 -- statusd for MPD (Music Player Daemon)
   6 -- bugs/requests/comments: delirium@hackish.org
   7
   8 -- requires that netcat is available in the path
   9
  10 local defaults={
  11     -- 500 or less makes seconds increment relatively smoothly while playing
  12     update_interval=500,
  13
  14     -- mpd server info (localhost:6600 are mpd defaults)
  15     address="localhost",
  16     port=6600,
  17
  18     -- mpd password (if any)
  19     password=nil,
  20
  21     -- display template
  22     -- ---
  23     -- can use the following:
  24     --   track metadata: %artist, %title, %num, %album, %year, %len
  25     --   current track position: %pos
  26     --   escape for the percent character: %%
  27
  28     -- a default template
  29     template = "%artist - %num - %title (%pos / %len)"
  30 }
  31
  32 local settings=table.join(statusd.get_config("mpd"), defaults)
  33
  34 local success
  35 local last_success
  36
  37 local function saferead(file)
  38         local data, err, errno
  39         repeat
  40                 data, err, errno = file:read()
  41         until errno ~= 4 -- EINTR
  42         return data, err, errno
  43 end
  44
  45 local function get_mpd_status()
  46     local cmd_string = "status\ncurrentsong\nclose\n"
  47     if settings.password ~= nil then
  48         cmd_string = "password " .. settings.password .. "\n" .. cmd_string
  49     end
  50     cmd_string = string.format('echo -n "%s" | netcat %s %d',
  51                                cmd_string, settings.address, settings.port)
  52
  53     last_success = success
  54     success = false
  55
  56     local mpd = io.popen(cmd_string, "r")
  57
  58     -- welcome msg
  59     local data = saferead(mpd)
  60     if data == nil or string.sub(data,1,6) ~= "OK MPD" then
  61         mpd:close()
  62         return "mpd not running"
  63     end
  64
  65     -- 'password' response (if necessary)
  66     if settings.password ~= nil then
  67         repeat
  68             data = saferead(mpd)
  69         until data == nil or string.sub(data,1,2) == "OK" or string.sub(data,1,3) == "ACK"
  70         if data == nil or string.sub(data,1,2) ~= "OK" then
  71             mpd:close()
  72             return "bad mpd password"
  73         end
  74     end
  75
  76     local info = {}
  77
  78     -- 'status' response
  79     repeat
  80         data = saferead(mpd)
  81         if data == nil then break end
  82
  83         local _,_,attrib,val = string.find(data, "(.-): (.*)")
  84         if attrib == "time" then
  85             _,_,info.pos,info.len = string.find(val, "(%d+):(%d+)")
  86             info.pos = string.format("%d:%02d", math.floor(info.pos / 60), math.mod(info.pos, 60))
  87             info.len = string.format("%d:%02d", math.floor(info.len / 60), math.mod(info.len, 60))
  88         elseif attrib == "state" then
  89             info.state = val
  90         end
  91     until string.sub(data,1,2) == "OK" or string.sub(data,1,3) == "ACK"
  92     if data == nil or string.sub(data,1,2) ~= "OK" then
  93         mpd:close()
  94         return "error querying mpd status"
  95     end
  96
  97     -- 'currentsong' response
  98     repeat
  99         data = saferead(mpd)
 100         if data == nil then break end
 101
 102         local _,_,attrib,val = string.find(data, "(.-): (.*)")
 103         if     attrib == "Artist" then info.artist = val
 104         elseif attrib == "Title"  then info.title  = val
 105         elseif attrib == "Album"  then info.album  = val
 106         elseif attrib == "Track"  then info.num    = val
 107         elseif attrib == "Date"   then info.year   = val
 108         end
 109     until string.sub(data,1,2) == "OK" or string.sub(data,1,3) == "ACK"
 110     if data == nil or string.sub(data,1,2) ~= "OK" then
 111         mpd:close()
 112         return "error querying current song"
 113     end
 114
 115     mpd:close()
 116
 117     success = true
 118
 119     -- done querying; now build the string
 120     if info.state == "play" then
 121         local mpd_st = settings.template
 122         -- fill in %values
 123         mpd_st = string.gsub(mpd_st, "%%([%w%_]+)", function (x) return(info[x]  or "") end)
 124         mpd_st = string.gsub(mpd_st, "%%%%", "%%")
 125         return mpd_st
 126     elseif info.state == "pause" then
 127         return "Paused"
 128     else
 129         return "No song playing"
 130     end
 131 end
 132
 133
 134 local mpd_timer
 135
 136 local function update_mpd()
 137     -- update unless there's an error that's not yet twice in a row, to allow
 138     -- for transient errors due to load spikes
 139     local mpd_st = get_mpd_status()
 140     if success or not last_success then
 141         statusd.inform("mpd", mpd_st)
 142     end
 143     mpd_timer:set(settings.update_interval, update_mpd)
 144 end
 145
 146 -- Init
 147 mpd_timer=statusd.create_timer()
 148 update_mpd()
 149