Mantiene la copertina YouTube se il telefono cade e avvia ffmpeg sul nodo, non via SSH.

Il relay HLS→RTMPS resta sul worker/agent del nodo assegnato, così tre dirette contemporanee restano in onda sul sito e sul canale della società senza schermo nero.

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/app/services/streams/youtube_relay.rb

@@ -1,6 +1,10 @@
+require "json"
+require "net/http"
+require "uri"
+
 module Streams
-  # Relay verso YouTube: legge RTMP/HLS da MediaMTX e inoltra su RTMPS (-c copy). Nessun overlay.
-  # ffmpeg gira solo sui worker Sidekiq con YOUTUBE_RELAY_WORKER=1 (coda youtube_relay).
+  # Relay verso YouTube: legge HLS da MediaMTX e inoltra su RTMPS (-c copy).
+  # Sul nodo cloud ffmpeg è avviato dall'agent locale (immagine CPX) all'avvio diretta.
   class YoutubeRelay
     class Error < StandardError; end
 
@@ -8,6 +12,7 @@ module Streams
     OWNER_KEY = "youtube_relay:owner:%s"
     OWNED_SET = "youtube_relay:owned:%s"
     QUEUE = :youtube_relay
+    QUEUE_PREFIX = "youtube_relay"
 
     class << self
       def worker?
@@ -18,18 +23,44 @@ module Streams
         ENV.fetch("RELAY_MAX_CONCURRENT", "4").to_i
       end
 
+      def local_node_slug
+        ENV["STREAM_NODE_SLUG"].presence || NodeRegistry::HOME_SLUG
+      end
+
+      def assigned_node_slug(session)
+        session.stream_node&.slug.presence || NodeRegistry::HOME_SLUG
+      end
+
+      def node_matches?(session)
+        assigned_node_slug(session) == local_node_slug
+      end
+
+      def queue_for(session)
+        "#{QUEUE_PREFIX}_#{assigned_node_slug(session)}"
+      end
+
+      def enqueue_ensure!(session, wait: nil)
+        opts = { queue: queue_for(session) }
+        opts[:wait] = wait if wait
+        YoutubeRelayEnsureJob.set(**opts).perform_later(session.id)
+      end
+
+      def enqueue_stop!(session)
+        YoutubeRelayStopJob.set(queue: queue_for(session)).perform_later(session.id)
+      end
+
       def start(session)
-        return unless worker?
+        return enqueue_ensure!(session) unless worker? && node_matches?(session)
 
         start_on_worker!(session)
       end
 
       # Non cancella owner/pid qui: solo il worker owner deve killare ffmpeg.
       def stop(session)
-        if worker? && owner_is_local?(session.id)
+        if worker? && owner_is_local?(session.id) && node_matches?(session)
           stop_on_worker!(session)
         else
-          YoutubeRelayStopJob.set(queue: QUEUE).perform_later(session.id)
+          enqueue_stop!(session)
         end
         true
       end
@@ -41,7 +72,7 @@ module Streams
         return false if pid.blank? && owner.present? && owner != worker_id && redis.ttl(format(OWNER_KEY, session_id)) <= 30
         return false if pid.blank?
 
-        return process_alive?(pid) if owner.blank? || owner == worker_id
+        return process_alive?(pid, session_id: session_id) if owner.blank? || owner == worker_id
 
         # Relay su altro host: attivo se lock owner ancora fresco.
         redis.ttl(format(OWNER_KEY, session_id)) > 30
@@ -52,15 +83,22 @@ module Streams
         return if session.terminal?
         return if session.stream_key.blank?
 
-        if worker?
+        if worker? && node_matches?(session)
           ensure_on_worker!(session)
         else
-          YoutubeRelayEnsureJob.set(queue: QUEUE).perform_later(session.id)
+          enqueue_ensure!(session)
         end
       end
 
       def ensure_on_worker!(session)
         return :not_worker unless worker?
+        unless node_matches?(session)
+          enqueue_ensure!(session, wait: 2.seconds)
+          Rails.logger.info(
+            "[YoutubeRelay] wrong_node local=#{local_node_slug} assigned=#{assigned_node_slug(session)} session=#{session.id}"
+          )
+          return :wrong_host
+        end
         return unless session.platform == "youtube"
         return if session.terminal?
         return if session.stream_key.blank?
@@ -68,7 +106,7 @@ module Streams
         return unless intake_available?(session)
 
         pid = pid_for(session.id)
-        if pid.present? && !process_alive?(pid.to_i)
+        if pid.present? && !process_alive?(pid.to_i, session_id: session.id)
           clear_local_ownership(session.id)
         end
 
@@ -78,8 +116,8 @@ module Streams
         end
 
         if at_capacity?
-          YoutubeRelayEnsureJob.set(wait: 5.seconds, queue: QUEUE).perform_later(session.id)
-          Rails.logger.info("[YoutubeRelay] at capacity worker=#{worker_id} session=#{session.id} requeue")
+          enqueue_ensure!(session, wait: 5.seconds)
+          Rails.logger.info("[YoutubeRelay] at capacity worker=#{worker_id} node=#{local_node_slug} session=#{session.id} requeue")
           return :at_capacity
         end
 
@@ -109,7 +147,7 @@ module Streams
           return :noop
         end
 
-        terminate_pid(pid)
+        terminate_pid(pid, session_id: session.id)
         clear_local_ownership(session.id)
         Rails.logger.info("[YoutubeRelay] stopped pid=#{pid} session=#{session.id} worker=#{worker_id}")
         :stopped
@@ -140,26 +178,88 @@ module Streams
 
         stop_on_worker!(session) if pid_for(session.id).present? && owner_is_local?(session.id)
 
+        # Due EnsureJob concorrenti (concurrency Sidekiq > 1) non devono spawnare due ffmpeg.
+        unless redis.set(format("youtube_relay:startlock:%s", session.id), worker_id, nx: true, ex: 20)
+          return pid_for(session.id).to_i
+        end
+
         log_path = log_file(session)
         FileUtils.mkdir_p(File.dirname(log_path))
         intake_source = mediamtx_intake_source(session)
         output = "rtmps://a.rtmps.youtube.com/live2/#{session.stream_key}"
 
-        pid = Process.spawn(
-          *youtube_ffmpeg_args(intake_source, output),
-          %i[out err] => log_path,
-          pgroup: true
-        )
-        Process.detach(pid)
+        pid = if relay_agent_enabled?
+                start_via_agent!(session)
+              else
+                spawn_ffmpeg!(youtube_ffmpeg_args(intake_source, output), log_path)
+              end
         store_pid(session.id, pid)
         claim_ownership!(session.id)
-        Rails.logger.info("[YoutubeRelay] started pid=#{pid} session=#{session.id} intake=#{intake_source.join(":")} worker=#{worker_id}")
+        Rails.logger.info(
+          "[YoutubeRelay] started pid=#{pid} session=#{session.id} intake=#{intake_source.join(':')} " \
+          "worker=#{worker_id} agent=#{relay_agent_url || '-'}"
+        )
         schedule_youtube_activate(session)
         pid
       rescue Errno::ENOENT => e
         raise Error, "ffmpeg non disponibile: #{e.message}"
       end
 
+      def relay_agent_url
+        ENV["STREAM_NODE_RELAY_AGENT_URL"].presence
+      end
+
+      def relay_agent_enabled?
+        relay_agent_url.present?
+      end
+
+      def relay_agent_secret
+        ENV["STREAM_NODE_AGENT_SECRET"].presence || ENV["MEDIAMTX_WEBHOOK_SECRET"].presence || ""
+      end
+
+      def spawn_ffmpeg!(args, log_path)
+        pid = Process.spawn(*args, %i[out err] => log_path, pgroup: true)
+        Process.detach(pid)
+        pid
+      end
+
+      def start_via_agent!(session)
+        payload = {
+          "session_id" => session.id,
+          "path" => session.mediamtx_path_name,
+          "rtmps" => "rtmps://a.rtmps.youtube.com/live2/#{session.stream_key}"
+        }
+        res = agent_request(Net::HTTP::Post, "/relays", payload)
+        pid = res["pid"].to_i
+        raise Error, "relay agent spawn failed: #{res.inspect}" if pid <= 0
+
+        File.write(
+          log_file(session),
+          "agent=#{relay_agent_url} pid=#{pid} path=#{session.mediamtx_path_name}\n"
+        )
+        pid
+      end
+
+      def agent_request(http_class, path, payload = nil)
+        uri = URI.parse("#{relay_agent_url.chomp('/')}#{path}")
+        http = Net::HTTP.new(uri.host, uri.port)
+        http.open_timeout = 5
+        http.read_timeout = 10
+        req = http_class.new(uri)
+        req["Authorization"] = "Bearer #{relay_agent_secret}" if relay_agent_secret.present?
+        req["Content-Type"] = "application/json"
+        req.body = JSON.generate(payload) if payload
+        res = http.request(req)
+        body = res.body.present? ? JSON.parse(res.body) : {}
+        unless res.is_a?(Net::HTTPSuccess)
+          raise Error, "relay agent #{path} HTTP #{res.code} #{body.inspect}"
+        end
+
+        body
+      rescue JSON::ParserError => e
+        raise Error, "relay agent JSON: #{e.message}"
+      end
+
       # Remux verso YouTube: video+audio copy (AAC già da app/slate a 48k mono).
       # HLS (ADTS) → FLV richiede -bsf:a aac_adtstoasc; RTMP ha già ASC in FLV tags.
       def youtube_ffmpeg_args(intake_source, output)
@@ -179,6 +279,9 @@ module Streams
         end
 
         common_head + [
+          "-reconnect", "1",
+          "-reconnect_streamed", "1",
+          "-reconnect_delay_max", "2",
           "-rw_timeout", "15000000",
           "-live_start_index", "-1",
           "-i", url,
@@ -190,14 +293,29 @@ module Streams
       end
 
       def mediamtx_intake_source(session)
-        base = session.mediamtx_internal_rtmp_url
+        rtmp_base, hls_base = intake_bases(session)
         if Mediamtx::PublisherOnline.active?(session)
-          return [:rtmp, "#{base.chomp('/')}/#{session.mediamtx_path_name}"]
+          return [:rtmp, "#{rtmp_base.chomp('/')}/#{session.mediamtx_path_name}"]
         end
 
         path = session.mediamtx_path_name
-        hls = session.mediamtx_internal_hls_url.chomp("/")
-        [:hls, "#{hls}/#{path}/index.m3u8"]
+        [:hls, "#{hls_base.chomp('/')}/#{path}/index.m3u8"]
+      end
+
+      # Sul nodo assegnato ffmpeg legge MediaMTX in loopback (o hostname Docker locale).
+      def intake_bases(session)
+        if relay_agent_enabled? && node_matches?(session)
+          return ["rtmp://127.0.0.1:1935", "http://127.0.0.1:8888"]
+        end
+
+        if node_matches?(session)
+          [
+            ENV["STREAM_NODE_LOCAL_RTMP_URL"].presence || session.mediamtx_internal_rtmp_url,
+            ENV["STREAM_NODE_LOCAL_HLS_URL"].presence || session.mediamtx_internal_hls_url
+          ]
+        else
+          [session.mediamtx_internal_rtmp_url, session.mediamtx_internal_hls_url]
+        end
       end
 
       def intake_available?(session)
@@ -257,7 +375,9 @@ module Streams
         redis.get(format(REDIS_KEY, session_id))
       end
 
-      def process_alive?(pid)
+      def process_alive?(pid, session_id: nil)
+        return agent_session_running?(session_id) if relay_agent_enabled? && session_id.present?
+
         stat = File.read("/proc/#{pid.to_i}/stat")
         return false if stat.split[2] == "Z"
 
@@ -267,12 +387,26 @@ module Streams
         false
       end
 
-      def terminate_pid(pid)
+      def agent_session_running?(session_id)
+        res = agent_request(Net::HTTP::Get, "/relays/#{session_id}")
+        res["running"] == true
+      rescue Error
+        false
+      end
+
+      def terminate_pid(pid, session_id: nil)
+        if relay_agent_enabled? && session_id.present?
+          agent_request(Net::HTTP::Delete, "/relays/#{session_id}")
+          return
+        end
+
         Process.kill("TERM", -pid.to_i)
         sleep 0.5
       rescue Errno::ESRCH
         nil
       else
+        return if relay_agent_enabled?
+
         begin
           Process.kill("KILL", -pid.to_i)
         rescue Errno::ESRCH