FMD (Douban FM Daemon)

FMD stands for Douban FM Daemon, inspired by MPD (Music Player Daemon).

FMD plays music from Douban FM in background and communicate with clients through TCP connections.

Config

The main config file is ~/.fmd/fmd.conf. Config file includes several sections.

In DoubanFM section, there are the following config items:

channel [int]   # Douban FM Channel id
uid [string]    # Douban FM user id
uname [string]  # Douban FM user name
token [string]  # Douban FM authorization token
expire [string] # token expire time

To get a complete channel list, try:

wget -q -O - "http://www.douban.com/j/app/radio/channels" | json_pp

To get your own uid, uname, token and expire, try:

wget -q -O - --post-data="email=[email]&password=[passwd]&app_name=radio_desktop_win&version=100" "http://www.douban.com/j/app/login" | json_pp

Replace [email] and [passwd] with your douban account and password.

In Output section, there are the following config items:

driver [string] # audio output driver, default is "alsa"
device [string] # audio output device, can be omitted
rate [int]      # audio ouput rate, default to 44100

In Server section, there are the following config items:

address [string]# server listen address, default to "localhost"
port [int]      # server listen port, default to 10098

Please create a config file before using FMD. A sample config file is:

[DoubanFM]
channel = 0
uid = 123456
uname = username
token = 1234abcd
expire = 1345000000

[Output]
driver = alsa
device = default
rate = 44100

[Server]
address = localhost
port = 10098

As FMD uses libao for audio output, users may found it useful to refer to libao's driver document when deciding which driver to use. For example, users of PulseAudio should change the Output section to:

[Output]
driver = pulse
device = 0
rate = 44100

Protocol

The communication between FMD and clients go throught TCP connection.

Commands client can send are play, stop, pause, toggle, skip, ban, rate, unrate, info and end. These commands are all self-explained except end will tell FMD server to exit.

FMD responses to most commands are json formmated strings containing current playing infomation.

{
   "len" : 0,
   "sid" : 967698,
   "status" : "play",
   "channel" : 0,
   "like" : 0,
   "artist" : "花儿乐队",
   "album" : "幸福的旁边",
   "cover" : "http://img1.douban.com/mpic/s4433542.jpg",
   "url" : "/subject/1404476/",
   "user" : "小强",
   "pos" : 5,
   "title" : "别骗我",
   "year" : 1999
}

The simplest FMD client is telnet:

telnet localhost 10098
Trying ::1...
Connection failed: Connection refused
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
info
{"status":"play","channel":0,"user":"小强","title":"What's My Name (Intro #1)","artist":"Rihanna / Drake", "album":"Promo Only Rhythm...","year":2010,"cover":"http://img1.douban.com/mpic/s4615061.jpg","url":"/subject/5951920/","sid":1561924,"like":0,"pos":107,"len":254}
toggle
{"status":"pause","channel":0,"user":"小强","title":"What's My Name (Intro #1)","artist":"Rihanna / Drake", "album":"Promo Only Rhythm...","year":2010,"cover":"http://img1.douban.com/mpic/s4615061.jpg","url":"/subject/5951920/","sid":1561924,"like":0,"pos":111,"len":254}
toggle
{"status":"play","channel":0,"user":"小强","title":"What's My Name (Intro #1)","artist":"Rihanna / Drake", "album":"Promo Only Rhythm...","year":2010,"cover":"http://img1.douban.com/mpic/s4615061.jpg","url":"/subject/5951920/","sid":1561924,"like":0,"pos":111,"len":254}
help
{"status":"error","message":"wrong command: help"}

FMC is a command line client for FMD.

Install

FMD is written in GNU C and depends on libcurl, json-c, mpg123, libao and alsa.

Known issues

Sometimes, FMD may use too much CPU. It's a known issue of libao and alsa. Trying fmc stop and fmc play may help.

Todos

• Add support for DJ channels.
• Add logs.
• Cover more error cases.
• Improve FMD protocol.