Adding Additional logging before throwing WorkerConfig for runtime: {workerRunTime} not found (#8236)

* Adding logging when loading functions using custom providers(IFunctionProvider implementations). Also Added debug log entry to log all the

* Moved the "reading functions" message inside AddMetadataFromCustomProviders

Author: kshyju

src/WebJobs.Script/Host/FunctionMetadataManager.cs

@@ -207,6 +207,8 @@ private void LoadCustomProviderFunctions(List<FunctionMetadata> functionMetadata
 
         private void AddMetadataFromCustomProviders(IEnumerable<IFunctionProvider> functionProviders, List<FunctionMetadata> functionMetadataList)
         {
+            _logger.FunctionMetadataProviderParsingFunctions();
+
             var functionProviderTasks = new List<Task<ImmutableArray<FunctionMetadata>>>();
             foreach (var functionProvider in functionProviders)
             {
@@ -218,6 +220,8 @@ private void AddMetadataFromCustomProviders(IEnumerable<IFunctionProvider> funct
             // This is used to make sure no duplicates are registered
             var distinctFunctionNames = new HashSet<string>(functionMetadataList.Select(m => m.Name));
 
+            _logger.FunctionMetadataProviderFunctionFound(functionMetadataListArray.Length);
+
             foreach (var metadataArray in functionMetadataListArray)
             {
                 if (!metadataArray.IsDefaultOrEmpty)

src/WebJobs.Script/Workers/Rpc/FunctionRegistration/RpcFunctionInvocationDispatcher.cs

@@ -233,6 +233,10 @@ public async Task InitializeAsync(IEnumerable<FunctionMetadata> functions, Cance
             {
                 // Only throw if workerConfig is null AND some functions have been found.
                 // With .NET out-of-proc, worker config comes from functions.
+
+                var allLanguageNamesFromWorkerConfigs = string.Join(",", _workerConfigs.Select(c => c.Description.Language));
+                _logger.LogDebug($"Languages present in WorkerConfig: {allLanguageNamesFromWorkerConfigs}");
+
                 throw new InvalidOperationException($"WorkerConfig for runtime: {_workerRuntime} not found");
             }