# Liquidsoap

## Audio Stream Generation

### dolebrai.liq

    #!/home/dbaelde/bin/liquidsoap -v

    set("root.max_latency",30.)
    set("server.telnet",true)
    set("server.socket.permissions",0o660)
    set("tag.encodings",["UTF-8","ISO-8859-1"])

    %include "dolutils.liq"

    root     = "/var/cache/dolebrai/"
    scripts  = "/home/dbaelde/scripts/"
    last_xml = "/home/dbaelde/dolebrai_public_html/last.xml"
    default  = "/var/cache/dolebrai/local/gelnior/jazz/07-patamouchto.mp3"

    add_protocol("dolebrai",
      fun (arg,delay) ->
        get_process_lines("#{scripts}dolebrai-filename #{quote(arg)}"))

    # === MAIN SOURCE ===

    # play explicit requests (from admins) or the playlist

    default = single(id="default",default)

    s =
      request.dynamic(id="scheduler",default_duration=30.,length=1.,
        fun () ->
          request(get_process_output("#{scripts}/scheduler.pl 2>> #{scripts}/log")))

    s = fallback([ request.queue(id="q"), s, default ])

    # Feedback is provided for any file played, be it from scheduler.pl, user
    # request via the queue or the default file.
    # By the way we refresh the XML describing the latest tracks.
    def feedback(m)
      system("#{scripts}/feedback.pl #{quote(m['filename'])} 2>> #{scripts}/logf")
      system("#{scripts}/last.rb > #{last_xml}")
    end
    # Add a telnet control to get info before metadata rewriting, used by last.rb
    s = store_metadata(size=20,id="history",s)
    s = on_metadata(feedback,s)

    # Prepend introductory tracks if necessary
    intro_mix = single("/var/cache/dolebrai/local/jingles/in_vitro/DJLEmb2.mp3")
    def choose_prepend(m)
      if m["prepend_track"] != "" then
        request.queue(interactive=false,queue=[request(m["prepend_track"])])
      elsif m["track_type"] == "mix" then
        # This is more reliable than prepend_track as intro_mix is always ready
        intro_mix
      else
        fallback([])
      end
    end
    s = prepend(s, choose_prepend)

    # === TWEAKS (blanks & metadata) ===

    # Cut blanks (bonus-tracks)
    s = skip_blank(length=7.,s)

    # Rewrite metadata
    s = rewrite_metadata([("title","$(title) (Dolebrai)"),
                          ("comment","http://dolebrai.net")],s)

    # === JINGLES ===

    # Metadata rewriting wrapper for jingle sources
    def jingle_meta(j)
      rewrite_metadata([("artist", "Dolebrai"),
                        ("title","Jingle (Dolebrai)"),
                        ("comment","http://dolebrai.net")],j)
    end

    # One source for static jingles, added between tracks
    jingles_stat = jingle_meta(playlist.safe(reload=3600,root^"jingles.static"))

    # Add cross-fading, inserting "static" jingles during the fade..
    def fade(jingles,s)
      fade_in = 2.
      fade_out = 2.
      start_next = 2.
      j = random(id="jrand",
                 strict=true,weights=[1,5],
                 [jingles, blank(id="bbb",duration=1.)])
      def fader(from,to)
        from = fade.out(duration=fade_out,from)
        to = fade.in(duration=fade_in,to)
        add(normalize=false,
            [ to,
              sequence([ j, fallback([]) ]),
              from ])
      end
      cross(duration=start_next,fader,s)
    end
    # s = fade(jingles_stat,s)
    # Use the fader defined in dolutils.liq
    # The smart fade tends to loose some metadata because there is no handling of
    # them in the generators...
    s = dole_fade(jingles=jingles_stat,s)

    # One for dynamic jingles, mixed on top of the stream with smooth starts/ends.
    jingles_dyn = jingle_meta(playlist(reload=3600,root^"jingles.dynamic"))
    jingles_dyn = fallback([request.queue(id="dynq"),jingles_dyn])
    s = smooth_add(normal=s,special=switch([({ 0m0s or 30m0s }, jingles_dyn)]))

    # === ADMIN INTERACTION ===
    # More interactivity to come, included live show hooks & co
    # s = mix([s,request.equeue(id="eq")])

    # === OUTPUT ===
    out_mp3 = output.icecast(%mp3,
        password="XXX", bitrate=64, samplerate=22050, quality=2,
        genre="Musique Libre",
        url="http://dolebrai.net",
        description="La radio des musiques libres")
    out_vorbis = output.icecast(%vorbis,
        password="XXX",
        genre="Musique Libre",
        description="La radio des musiques libres")

    # s = normalize(s)
    s = audio_process(s)

    out_vorbis(port=8000,mount="dolebrai.ogg",s)
    out_mp3(port=8000,mount="dolebrai.mp3",s)

    # out(port=7144,s) # One for peercast

    # Start a watchdog to tell us if liquidsoap crashes
    system("#{scripts}watchdog-dolebrai &")

Download