Add IPC example, and tidy up usage of Console.

Author: ioquatix

examples/ipc/readme.md

@@ -0,0 +1,67 @@
+# IPC Example
+
+This example demonstrates Inter-Process Communication (IPC) using Unix domain sockets with two async services:
+
+- **IPC Server**: Listens on a Unix domain socket and responds with "Hello World" to each connection
+- **IPC Client**: Periodically connects to the server and prints the received message
+
+Both services use `ContainerService` as the base class, which provides built-in health checking, process title formatting, and container management.
+
+## Configuration
+
+The example uses a shared environment module (`IPCEnvironment`) that includes `ContainerEnvironment` for container configuration:
+
+```ruby
+module IPCEnvironment
+	include Async::Service::ContainerEnvironment
+	
+	def ipc_socket_path
+		File.expand_path("service.ipc", Dir.pwd)
+	end
+	
+	def ipc_connection_timeout
+		5.0
+	end
+	
+	def count
+		1  # Run single instance of each service
+	end
+end
+```
+
+### Customizing the Socket Path
+
+You can override the socket path by modifying the `IPCEnvironment` module:
+
+```ruby
+module IPCEnvironment
+	def ipc_socket_path
+		"/tmp/my_custom_ipc.sock"
+	end
+end
+```
+
+## Usage
+
+```bash
+# Run both services together:
+bundle exec service.rb
+```
+
+## Expected Output
+
+The server will start first and begin listening:
+
+```
+IPC Server listening on /Users/your-username/your-project/service.ipc
+```
+
+The client will then periodically connect:
+
+```
+Connected to server
+Received from server: Hello World
+Connection closed
+```
+
+This process repeats every 5 seconds (2 second delay + 3 second wait), demonstrating persistent IPC communication between services.

examples/ipc/service.rb

@@ -0,0 +1,116 @@
+#!/usr/bin/env async-service
+# frozen_string_literal: true
+
+# Released under the MIT License.
+# Copyright, 2025, by Samuel Williams.
+
+require "socket"
+require "async"
+require "async/service/container_service"
+require "async/service/container_environment"
+
+# Server service that listens on a Unix domain socket and responds with "Hello World"
+class IPCServer < Async::Service::ContainerService
+	def run(instance, evaluator)
+		socket_path = evaluator.ipc_socket_path
+		
+		# Clean up any existing socket
+		File.unlink(socket_path) if File.exist?(socket_path)
+		
+		# Create Unix domain socket server
+		server = UNIXServer.new(socket_path)
+		
+		Console.info(self) {"IPC Server listening on #{socket_path}"}
+		instance.ready!
+		
+		begin
+			while true
+				# Accept incoming connections
+				client = server.accept
+				Console.info(self) {"Client connected"}
+				
+				# Send greeting
+				client.write("Hello World\n")
+				client.close
+				
+				Console.info(self) {"Sent greeting and closed connection"}
+			end
+		rescue => error
+			Console.error(self, error)
+		ensure
+			server&.close
+			File.unlink(socket_path) if File.exist?(socket_path)
+		end
+		
+		return server
+	end
+end
+
+# Client service that periodically connects to the server
+class IPCClient < Async::Service::ContainerService
+	def run(instance, evaluator)
+		socket_path = evaluator.ipc_socket_path
+		timeout = evaluator.ipc_connection_timeout
+		
+		Console.info(self) {"IPC Client starting - will connect to #{socket_path}"}
+		instance.ready!
+		
+		Async do |task|
+			while true
+				begin
+					# Wait a bit before first connection attempt
+					task.sleep(2)
+					
+					# Connect to server
+					client = UNIXSocket.new(socket_path)
+					Console.info(self) {"Connected to server"}
+					
+					# Read response
+					response = client.readline.chomp
+					puts "Received from server: #{response}"
+					
+					client.close
+					Console.info(self) {"Connection closed"}
+					
+					# Wait before next connection
+					task.sleep(3)
+					
+				rescue Errno::ENOENT
+					Console.warn(self) {"Server socket not found at #{socket_path}, retrying..."}
+					task.sleep(2)
+				rescue => error
+					Console.error(self, error)
+					task.sleep(2)
+				end
+			end
+		end
+	end
+end
+
+module IPCEnvironment
+	include Async::Service::ContainerEnvironment
+	
+	def ipc_socket_path
+		File.expand_path("service.ipc", Dir.pwd)
+	end
+	
+	def ipc_connection_timeout
+		5.0
+	end
+	
+	# Override to use only 1 instance for both services.
+	def count
+		1
+	end
+end
+
+# Define both services using the shared IPC environment:
+service "ipc-server" do
+	service_class IPCServer
+	include IPCEnvironment
+end
+
+service "ipc-client" do
+	service_class IPCClient
+	include IPCEnvironment
+end

fixtures/async/service/sleep_service.rb

@@ -13,7 +13,7 @@ def setup(container)
 
 				container.run(count: 1, restart: true) do |instance|
 					# Use log level:
-					Console.logger.level = @environment.evaluator.log_level
+					Console.level = @environment.evaluator.log_level
 
 					if container.statistics.failed?
 						Console.debug(self, "Child process restarted #{container.statistics.restarts} times.")

lib/async/service/loader.rb

@@ -38,8 +38,6 @@ def self.load_file(configuration, path)
 				loader.instance_eval(File.read(path), path)
 			end
 
-			# Load a file relative to the loader's root directory.
-			# @parameter path [String] The path to the file to load.
 			def load_file(path)
 				Loader.load_file(@configuration, File.expand_path(path, @root))
 			end