public async Task CreateOrUpdate()

in src/WebJobs.Script.WebHost/Management/WebFunctionsManager.cs [95:172]
55 lines of code
11 McCabe index (conditional complexity)

        public async Task<(bool Success, bool ConfigChanged, FunctionMetadataResponse Response)> CreateOrUpdate(string name, FunctionMetadataResponse functionMetadata, HttpRequest request)
        {
            var hostOptions = _applicationHostOptions.CurrentValue.ToHostOptions();
            var configChanged = false;
            var functionDir = Path.Combine(hostOptions.RootScriptPath, name);

            // Make sure the function folder exists
            if (!FileUtility.DirectoryExists(functionDir))
            {
                // Cleanup any leftover artifacts from a function with the same name before.
                DeleteFunctionArtifacts(functionMetadata);
                Directory.CreateDirectory(functionDir);
            }

            string newConfig = null;
            string configPath = Path.Combine(functionDir, ScriptConstants.FunctionMetadataFileName);
            string dataFilePath = Extensions.FunctionMetadataExtensions.GetTestDataFilePath(name, hostOptions);

            // If files are included, write them out
            if (functionMetadata?.Files != null)
            {
                // If the config is passed in the file collection, save it and don't process it as a file
                if (functionMetadata.Files.TryGetValue(ScriptConstants.FunctionMetadataFileName, out newConfig))
                {
                    functionMetadata.Files.Remove(ScriptConstants.FunctionMetadataFileName);
                }

                // Delete all existing files in the directory. This will also delete current function.json, but it gets recreated below
                FileUtility.DeleteDirectoryContentsSafe(functionDir);

                await functionMetadata
                    .Files
                    .Select(e => FileUtility.WriteAsync(Path.Combine(functionDir, e.Key), e.Value))
                    .WhenAll();
            }

            // Get the config (if it was not already passed in as a file)
            if (newConfig == null && functionMetadata?.Config != null)
            {
                newConfig = JsonConvert.SerializeObject(functionMetadata?.Config, Formatting.Indented);
            }

            // Get the current config, if any
            string currentConfig = null;
            if (FileUtility.FileExists(configPath))
            {
                currentConfig = await FileUtility.ReadAsync(configPath);
            }

            // Save the file and set changed flag is it has changed. This helps optimize the syncTriggers call
            if (newConfig != currentConfig)
            {
                await FileUtility.WriteAsync(configPath, newConfig);
                configChanged = true;
            }

            if (functionMetadata.TestData != null && !_hostingConfigOptions.CurrentValue.IsTestDataSuppressionEnabled)
            {
                await FileUtility.WriteAsync(dataFilePath, functionMetadata.TestData);
            }

            // Using HostFunctionMetadataProvider instead of IFunctionMetadataManager. More details logged here https://github.com/Azure/azure-functions-host/issues/10691
            var metadata = (await _hostFunctionMetadataProvider.GetFunctionMetadataAsync(_languageWorkerOptions.CurrentValue.WorkerConfigs, true))
                .FirstOrDefault(metadata => Utility.FunctionNamesMatch(metadata.Name, name));

            bool success = false;
            FunctionMetadataResponse functionMetadataResult = null;
            if (metadata != null)
            {
                functionMetadataResult = await GetFunctionMetadataResponseAsync(metadata, hostOptions, request, _hostingConfigOptions.CurrentValue.IsTestDataSuppressionEnabled);
                success = true;
            }

            // we need to sync triggers if config changed, or the files changed
            await _functionsSyncManager.TrySyncTriggersAsync();

            return (success, configChanged, functionMetadataResult);
        }