Tau - further work expanding link API

Now supports disabling and enabling link as well as auto-updating a cached BPM value which removes the need to round-trip an API query for every BPM lookup (API queries can be forced though)

Author: samaaron

app/server/erlang/tau/src/tau_server/tau_server_api.erl

@@ -170,6 +170,18 @@ loop(State) ->
                     send_to_link({link_rpc, UUID, get_num_peers}, State),
                     ?MODULE:loop(State);
 
+
+                {cmd, ["/link-disable"]=Cmd} ->
+                    debug_cmd(Cmd),
+                    send_to_link({link_disable}, State),
+                    ?MODULE:loop(State);
+
+                {cmd, ["/link-enable"]=Cmd} ->
+                    debug_cmd(Cmd),
+                    send_to_link({link_enable}, State),
+                    ?MODULE:loop(State);
+
+
                 {cmd, Cmd} ->
                     log("Unknown command:: ~p~n", [Cmd]),
                     ?MODULE:loop(State)

app/server/erlang/tau/src/tau_server/tau_server_cue.erl

@@ -121,6 +121,7 @@ loop(State) ->
                   cue_port := CuePort,
                   in_socket := InSocket} ->
                     forward_internal_cue(CueHost, CuePort, InSocket, "/link/tempo-change", [Tempo]),
+                    send_api_tempo_update(CueHost, CuePort, InSocket, Tempo),
                     ?MODULE:loop(State);
                 _ ->
                     debug("Link cue forwarding disabled - ignored tempo change ~n", []),
@@ -324,6 +325,12 @@ send_api_reply(State, UUID, Args) ->
     send_udp(InSocket, CueHost, CuePort, Bin),
     ok.
 
+send_api_tempo_update(CueHost, CuePort, InSocket, Tempo) ->
+    Bin = osc:encode(["/link-tempo-change", "erlang", Tempo]),
+    send_udp(InSocket, CueHost, CuePort, Bin),
+    debug("sending link tempo update [~p] to ~p:~p~n", [Tempo, CueHost, CuePort]),
+    ok.
+
 forward_internal_cue(CueHost, CuePort, InSocket, Path, Args) ->
     Bin = osc:encode(["/internal-cue", "erlang", Path | Args]),
     send_udp(InSocket, CueHost, CuePort, Bin),

app/server/erlang/tau/src/tau_server/tau_server_link.erl

@@ -89,6 +89,17 @@ loop(State) ->
             maps:get(cue_server, State) ! {link, stop},
             ?MODULE:loop(State);
 
+
+        {link_disable} ->
+            log("Disabling link~n", []),
+            sp_link:enable(false),
+            ?MODULE:loop(State);
+
+        {link_enable} ->
+            log("Enabling link~n", []),
+            sp_link:enable(true),
+            ?MODULE:loop(State);
+
         {link_rpc, UUID, get_current_time} ->
             Time = sp_link:get_current_time_microseconds(),
             log("Received link rpc current_time [~p]~n", [Time]),

app/server/ruby/lib/sonicpi/tau_api.rb

@@ -38,6 +38,7 @@ def initialize(ports, handlers)
       @link_time = nil
       @local_time = nil
 
+      @tempo = nil
       Thread.new do
         initialize_link_info!
       end
@@ -68,11 +69,17 @@ def link_current_time
 
     def link_current_and_local_time
       api_rpc("/link-get-curent-and-local-time") << Time.now
-    end
 
-    def link_tempo
-      res = api_rpc("/link-get-tempo")
-      res[0]
+    def link_tempo(force_api_call=false)
+      if force_api_call
+        res = api_rpc("/link-get-tempo")
+        @tempo = res[0]
+        return res[0]
+      elsif @tempo
+        return @tempo
+      else
+        @tempo = link_tempo(true)
+      end
     end
 
     def link_num_peers
@@ -90,6 +97,16 @@ def link_get_time_at_beat(beat, quantum)
       res[0]
     end
 
+
+
+    def link_disable
+      @tau_comms.send("/link-disable")
+    end
+
+    def link_enable
+      @tau_comms.send("/link-enable")
+    end
+
     def midi_system_start!
       @tau_comms.send("/stop-start-midi-cues", 1)
     end
@@ -137,6 +154,12 @@ def initialize_link_info!
     end
 
     def add_incoming_api_handlers!
+      @tau_comms.add_method("/link-tempo-change") do |args|
+        gui_id = args[0]
+        tempo = args[1].to_f
+        @tempo = tempo
+      end
+
       @tau_comms.add_method("/midi-ins") do |args|
         gui_id = args[0]
         ins = args[1..-1]