Extend MQTTnet.Server application.

2026-10-16 01:03:01 +08:00 · 2019-03-05 21:37:00 +01:00
parent b68247f56d
commit 6f5f507323
32 changed files with 1114 additions and 309 deletions
@@ -0,0 +1,130 @@
+using System;
+using System.Collections.Generic;
+using System.Dynamic;
+using System.IO;
+using System.Linq;
+using System.Text;
+using Microsoft.Extensions.Logging;
+using Microsoft.Scripting;
+using Microsoft.Scripting.Hosting;
+
+namespace MQTTnet.Server.Scripting
+{
+    public class PythonScriptHostService
+    {
+        private readonly IDictionary<string, object> _proxyObjects = new ExpandoObject();
+        private readonly List<PythonScriptInstance> _scriptInstances = new List<PythonScriptInstance>();
+        private readonly ILogger<PythonScriptHostService> _logger;
+        private readonly ScriptEngine _scriptEngine;
+        
+        public PythonScriptHostService(PythonIOStream pythonIOStream, ILogger<PythonScriptHostService> logger)
+        {
+            _logger = logger ?? throw new ArgumentNullException(nameof(logger));
+
+            _scriptEngine = IronPython.Hosting.Python.CreateEngine();
+            _scriptEngine.Runtime.IO.SetOutput(pythonIOStream, Encoding.UTF8);
+        }
+
+        public void Configure()
+        {
+            AddSearchPaths(_scriptEngine);
+
+            var scriptsDirectory = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "Scripts");
+            foreach (var filename in Directory.GetFiles(scriptsDirectory, "*.py", SearchOption.AllDirectories).OrderBy(file => file))
+            {
+                TryInitializeScript(filename);
+            }
+        }
+
+        public void RegisterProxyObject(string name, object action)
+        {
+            if (name == null) throw new ArgumentNullException(nameof(name));
+            if (action == null) throw new ArgumentNullException(nameof(action));
+
+            _proxyObjects.Add(name, action);
+        }
+
+        public void InvokeOptionalFunction(string name, object parameters)
+        {
+            if (name == null) throw new ArgumentNullException(nameof(name));
+
+            lock (_scriptInstances)
+            {
+                foreach (var pythonScriptInstance in _scriptInstances)
+                {
+                    try
+                    {
+                        pythonScriptInstance.InvokeOptionalFunction(name, parameters);
+                    }
+                    catch (Exception exception)
+                    {
+                        _logger.LogError(exception, $"Error while invoking function '{name}' at script '{pythonScriptInstance.Name}'.");
+                    }
+                }
+            }
+        }
+
+        private void TryInitializeScript(string filename)
+        {
+            try
+            {
+                var scriptName = new FileInfo(filename).Name;
+
+                _logger.LogTrace($"Initializing Python script '{scriptName}'...");
+                var code = File.ReadAllText(filename);
+
+                var scriptInstance = CreateScriptInstance(scriptName, code);
+                scriptInstance.InvokeOptionalFunction("initialize");
+
+                _scriptInstances.Add(scriptInstance);
+
+                _logger.LogInformation($"Initialized script '{scriptName}'.");
+            }
+            catch (Exception exception)
+            {
+                _logger.LogError(exception, $"Error while initializing script '{new FileInfo(filename).Name}'.");
+            }
+        }
+
+        private PythonScriptInstance CreateScriptInstance(string name, string code)
+        {
+            var scriptScope = _scriptEngine.CreateScope();
+
+            var source = scriptScope.Engine.CreateScriptSourceFromString(code, SourceCodeKind.File);
+            var compiledCode = source.Compile();
+
+            scriptScope.SetVariable("mqtt_net_server", _proxyObjects);
+            compiledCode.Execute(scriptScope);
+            
+            return new PythonScriptInstance(name, scriptScope);
+        }
+
+        private void AddSearchPaths(ScriptEngine scriptEngine)
+        {
+            var paths = new List<string>
+            {
+                Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "Lib"),
+                "/usr/lib/python2.7",
+                @"C:\Python27\Lib"
+            };
+            
+            AddSearchPaths(scriptEngine, paths);
+        }
+
+        private void AddSearchPaths(ScriptEngine scriptEngine, IEnumerable<string> paths)
+        {
+            var searchPaths = scriptEngine.GetSearchPaths();
+
+            foreach (var path in paths)
+            {
+                if (Directory.Exists(path))
+                {
+                    searchPaths.Add(path);
+                    _logger.LogInformation($"Added Python lib path: {path}");
+                }
+            }
+
+            scriptEngine.SetSearchPaths(searchPaths);
+        }
+    }
+}