Handle FunctionEnvironmentReloadRequest (#441)

Author: AnatoliB

src/RequestProcessor.cs

@@ -339,6 +339,19 @@ internal StreamingMessage ProcessInvocationCancelRequest(StreamingMessage reques
 
         internal StreamingMessage ProcessFunctionEnvironmentReloadRequest(StreamingMessage request)
         {
+            var stopwatch = new Stopwatch();
+            stopwatch.Start();
+
+            var environmentReloadRequest = request.FunctionEnvironmentReloadRequest;
+            foreach (var (name, value) in environmentReloadRequest.EnvironmentVariables)
+            {
+                Environment.SetEnvironmentVariable(name, value);
+            }
+
+            var rpcLogger = new RpcLogger(_msgStream);
+            rpcLogger.SetContext(request.RequestId, null);
+            rpcLogger.Log(isUserOnlyLog: false, LogLevel.Trace, string.Format(PowerShellWorkerStrings.EnvironmentReloadCompleted, stopwatch.ElapsedMilliseconds));
+
             StreamingMessage response = NewStreamingMessageTemplate(
                 request.RequestId,
                 StreamingMessage.ContentOneofCase.FunctionEnvironmentReloadResponse,

src/resources/PowerShellWorkerStrings.resx

@@ -313,4 +313,7 @@
   <data name="InvalidFunctionsWorkerRuntimeVersion" xml:space="preserve">
     <value>Invalid PowerShell version specified in the {0} environment variable: {1}. This version is not supported on Azure Functions Runtime v2.</value>
   </data>
+  <data name="EnvironmentReloadCompleted" xml:space="preserve">
+    <value>Environment reload completed in {0} ms.</value>
+  </data>
 </root>