Initial functioning work to get IPC working via UNIX sockets since ractors are still not a viable option :sad:

lib/constants.rb

@@ -7,5 +7,6 @@ module W3DHubLauncher
   DEFAULT_PACKAGE_CACHE_PATH = "#{CACHE_PATH}/packages".freeze
   DEFAULT_APPLICATIONS_PATH = "#{Dir.home}/.local/share/#{DIRECTORY_NAME}/applications".freeze
 
+  IPC_PATH = "/tmp/w3dhub_linux_launcher.sock"
   USER_AGENT = "#{NAME} v#{VERSION}".freeze
 end

lib/gui_ext.rb

@@ -4,6 +4,8 @@ module W3DHubLauncher
     WHITE_IMAGE = Gosu.render(64, 64, retro: true) { Gosu.draw_rect(0, 0, 32, 32, Gosu::Color::WHITE) }
 
     def safe_get_image(path, retro: false)
+      raise RuntimeError, "Images may only be loaded from the main thread!" unless Thread.current == Thread.main
+
       return get_image(path, retro: retro) if File.exist?(path)
 
       path = "#{ROOT_PATH}/media/default.png"
@@ -21,5 +23,9 @@ module W3DHubLauncher
         circle.draw(0, 0, 1, 1, 1, 0xff_ffffff, :multiply)
       end
     end
+
+    def on_main_thread(block)
+      window.add_to_queue(block)
+    end
   end
 end

lib/pages/boot/initial_setup.rb

@@ -51,7 +51,7 @@ module W3DHubLauncher
 
                 Worker::Api.update_settings({}) do |result|
                   if result.okay?
-                    page(Page::Boot::StartUp)
+                     on_main_thread(proc { page(Page::Boot::StartUp) })
                   else
                     btn.enabled = true
                   end

lib/pages/games.rb

@@ -26,7 +26,7 @@ module W3DHubLauncher
           # game info container
           stack(width: 340, height: 1.0) do
             # logo
-            image safe_get_image("/run/media/cyberarm/Storage/W3DHub/Launcher/package-cache/games/apb/logo.png.package"), width: 1.0, max_height: 124
+            image safe_get_image("#{ROOT_PATH}/media/default.png"), width: 1.0, max_height: 124
 
             # web links
             stack(width: 1.0, fill: true, padding: 0, padding_top: LARGE_PADDING) do

lib/states/boot.rb

@@ -5,7 +5,7 @@ module W3DHubLauncher
         super
 
         # root container - background image
-        stack(width: 1.0, height: 1.0, background_image: safe_get_image("/run/media/cyberarm/Storage/W3DHub/Launcher/package-cache/games/apb/background.png.package"), background_image_mode: :fill) do
+        stack(width: 1.0, height: 1.0, background_image: safe_get_image("#{ROOT_PATH}/media/background.png"), background_image_mode: :fill) do
           # root container - background image tint
           flow(width: 1.0, height: 1.0, background: 0xaa_000000) do
             # content container

lib/states/interface.rb

@@ -5,7 +5,7 @@ module W3DHubLauncher
         super
 
         # root container - background image
-        stack(width: 1.0, height: 1.0, background_image: safe_get_image("/run/media/cyberarm/Storage/W3DHub/Launcher/package-cache/games/apb/background.png.package"), background_image_mode: :fill) do
+        stack(width: 1.0, height: 1.0, background_image: safe_get_image("#{ROOT_PATH}/media/background.png"), background_image_mode: :fill) do
           # root container - background image tint
           stack(width: 1.0, height: 1.0, background: ALPHA_BLACK) do
             # content container

lib/window.rb

@@ -4,6 +4,8 @@ module W3DHubLauncher
       self.show_cursor = true
       self.caption = format("%s | v%s (%s)", NAME, VERSION, VERSION_NAME) # "Cyberarm's W3D Hub Linux Launcher | v2.0.0 alpha"
 
+      @main_thread_queue = []
+
       push_state(States::Boot)
       # push_state(States::Interface)
     end
@@ -13,9 +15,19 @@ module W3DHubLauncher
     end
 
     def update
+      while(block = @main_thread_queue.shift)
+        block.call
+      end
+
+      WORKER.service
+
       super
 
       sleep 0.001
     end
+
+    def add_to_queue(block)
+      @main_thread_queue << block
+    end
   end
 end

lib/worker.rb

@@ -3,16 +3,28 @@ module W3DHubLauncher
     Response = Data.define(:status, :request_id, :data)
 
     def initialize
+    end
+
+    def connect
+      puts :connect
+
+      @socket = UNIXSocket.new(IPC_PATH)
+    end
+
+    def connected?
+      @socket && !@socket.closed?
+    end
+
+    def listen
+      init_server
+    end
+
+    def init_server
       @threads = []
       @requests = []
 
-      @settings = # Settings.new
+      @settings = 0# Settings.new
 
-      # next available request_id to assign incoming requests
-      @request_id = 0
-
-      # listen for requests from frontend
-      listener = Thread.new { listen }
       # connect to and monitor GSH web service
       @threads << Thread.new { game_server_hub_websocket }
       # connect to and monitor Backend web service
@@ -20,20 +32,26 @@ module W3DHubLauncher
 
       @w3dhub_api = W3DHubLauncher::W3DHubApi.new
 
-      listener.join
+      Async do |task|
-    end
+        UNIXServer.open(IPC_PATH) do |server|
+          while(socket = server.accept)
+            task.async do
+              data = socket.gets
+              json = JSON.parse(data)
+              query = Request::Query.new(type: json["type"].to_sym, request_id: json["request_id"], data: json["data"])
 
-    def listen
+              pp [:server_incoming, data, query]
-      loop do
-        query = Ractor.receive
-        pp query
 
               if respond_to?(query.type)
-          Async do
+                response = send(query.type, query)
-            send(query.type, query)
+                pp [:server_to_client, response]
+                payload = { status: response.status, request_id: response.request_id, data: response.data.data }.to_json
+                socket.puts(payload)
               end
-        else
+            end
-          raise "UNKNOWN REQUEST: #{query}"
+          end
+        ensure # manually delete "socket"
+          File.delete(IPC_PATH)
         end
       end
     end
@@ -44,6 +62,45 @@ module W3DHubLauncher
     def backend_websocket
     end
 
+    # Send request to server
+    def request(query)
+      pp [:client_request, query]
+      payload = { type: query.type, request_id: query.request_id, data: query.data }.to_json
+
+      if respond_to?(query.type)
+        @socket.puts(payload)
+      else
+        raise "UNKNOWN REQUEST: #{query}"
+      end
+    end
+
+    def service
+      data = @socket.read_nonblock(1_048_576) # 1 MB
+      pp [:CLIENT, data]
+      json = JSON.parse(data)
+      response = Response.new(status: json["status"], request_id: json["request_id"], data: json["data"])
+      request = W3DHubLauncher::Worker::Request.requests.find { |r| r.request_id == response.request_id }
+
+      pp [json, response, request]
+      return unless request
+
+      CyberarmEngine::Window.instance&.add_to_queue(proc {
+        request.handle_event(
+          response.status,
+          CyberarmEngine::Result.new(data: response.data, error: response.status.negative? ? true : nil)
+        )
+      })
+
+    rescue Errno::EWOULDBLOCK
+    end
+
+    def deliver_response(result, query)
+      response = Response.new(result.okay? ? Request::STATUS_COMPLETE : Request::STATUS_ERROR, query.request_id, result)
+      pp response
+
+      response
+    end
+
     #
     # ------------ query / request handlers ------------
     #
@@ -54,11 +111,9 @@ module W3DHubLauncher
     end
 
     def w3dhub_api_call(query)
-      result = @w3dhub_api.send(query.data[:call], *(query.data[:arguments] || []))
+      result = @w3dhub_api.send(query.data["call"], *(query.data["arguments"] || []))
-      pp result
-      response = Response.new(result.okay? ? Request::STATUS_COMPLETE : Request::STATUS_ERROR, query.request_id, result)
 
-      Ractor.main.send(response)
+      deliver_response(result, query)
     end
 
     def update_settings(query)
@@ -67,9 +122,7 @@ module W3DHubLauncher
       FileUtils.mkdir_p(W3DHubLauncher::CONFIG_PATH) # FIXME: FAILABLE!
       File.write("#{W3DHubLauncher::CONFIG_PATH}/settings.json", query.data) # FIXME: FAILABLE!
       result.data = query.data
-      response = Response.new(result.okay? ? Request::STATUS_COMPLETE : Request::STATUS_ERROR, query.request_id, result)
+      deliver_response(result, query)
-
-      Ractor.main.send(response)
     end
 
     def install_application(query)

lib/worker/api.rb

@@ -1,4 +1,4 @@
-# Helper for launcher frontend to safely communicate with ractor (prevent deadlocks and concurrent access errors)
+# Helper for launcher frontend to safely communicate with launcher backend
 
 module W3DHubLauncher
   class Worker

lib/worker/request.rb

@@ -47,7 +47,7 @@ module W3DHubLauncher
 
       def enqueue(type, id, data)
         Request.requests << self
-        W3DHubLauncher::WORKER.send(Query.new(type, id, data))
+        W3DHubLauncher::WORKER.request(Query.new(type, id, data))
       end
 
       # event from Worker received

lib/worker/w3dhub_api.rb

@@ -21,7 +21,7 @@ module W3DHubLauncher
       array << ["content-type", "application/x-www-form-urlencoded"] if form_encoded
       array << ["authorization", "Bearer #{@access_token}"] if @access_token
 
-      pp array
+      # pp array
 
       array
     end
@@ -36,6 +36,7 @@ module W3DHubLauncher
             if response.success?
               result.data = response.read
             else
+              pp response
               result.error = true
             end
           end
@@ -99,9 +100,24 @@ module W3DHubLauncher
 
     def fetch_applications
       result = CyberarmEngine::Result.new
-      primary_result = fetch("#{PRIMARY_W3DHUB_API_ENDPOINT}/apis/launcher/1/get-applications")
+      # If we're not signed in, then the primary backend will try to redirect us to the alternate backend. So skip it if we're not signed in.
+      primary_result = @access_token ? fetch("#{PRIMARY_W3DHUB_API_ENDPOINT}/apis/launcher/1/get-applications") : CyberarmEngine::Result.new(error: true)
       alternate_result = fetch("#{ALTERNATIVE_W3DHUB_API_ENDPOINT}/apis/launcher/1/get-applications")
 
+      # We've failed to retrieve data
+      if primary_result.error? && alternate_result.error?
+        return result
+      # We've only gotten data back from the primary backend
+      elsif primary_result.okay? && alternate_result.error?
+        result.data = primary_result.data
+        return result
+      # We've only gotten data back from the alternate backend
+      elsif primary_result.error? && alternate_result.okay?
+        result.data = alternate_result.data
+        return result
+      end
+
+      # We've gotten data back from both backends, merge them.
       pp [primary_result, alternate_result]
 
       # FIXME: Merge primary and alternate results

w3d_hub_linux_launcher.rb

@@ -4,6 +4,7 @@ rescue LoadError
   require "cyberarm_engine"
 end
 
+require "socket"
 require "rexml"
 require "base64"
 require "logger"
@@ -44,30 +45,20 @@ require_relative "lib/worker/tasks/repair_application"
 require_relative "lib/worker/tasks/update_application"
 
 module W3DHubLauncher
-  WORKER = Ractor.new(name: "Parallel Worker") { W3DHubLauncher::Worker.new }
+  # UNIXServer
-end
+  Thread.new do
-
+    W3DHubLauncher::Worker.new.listen
-# Hello, I exist because there presently exists no way to ask if there are pending
-# messages in our ractors mailbox without making a blocking call which is a big no no
-# for a GUI application. :|
-#
-# Keep an eye on: https://bugs.ruby-lang.org/issues/21930: "Add Ractor#empty? method to check for pending messages without blocking"
-#
-# NOTE: May need to mangle Window#update to do ruby-land sleep so thread gets time to process :(
-Thread.new do
-  loop do
-    response = Ractor.receive
-    pp response
-
-    request = W3DHubLauncher::Worker::Request.requests.find { |r| r.request_id == response.request_id }
-    request&.handle_event(response.status, response.data)
   end
+
+  # UNIXSocket / client
+  WORKER = W3DHubLauncher::Worker.new
+  WORKER.connect
 end
 
 # 10.times do
-  W3DHubLauncher::Worker::Request.new(:w3dhub_api_call, { call: :fetch_applications }) do |result|
+  # W3DHubLauncher::Worker::Request.new(:w3dhub_api_call, { call: :fetch_applications }) do |result|
-    pp result
+  #   pp [:CALLBACK, result]
-  end
+  # end
 # end
 
 window = W3DHubLauncher::Window.new(width: 1280, height: 800, resizable: true)