public static async Task Main()

in Hands-on lab/lab-files/TransactionGenerator/Program.cs [352:455]
82 lines of code
6 McCabe index (conditional complexity)

        public static async Task Main(string[] args)
        {
            // Setup configuration to either read from the appsettings.json file (if present) or environment variables.
            var builder = new ConfigurationBuilder()
                .SetBasePath(Directory.GetCurrentDirectory())
                .AddJsonFile("appsettings.json", optional: true, reloadOnChange: true)
                .AddEnvironmentVariables();

            _configuration = builder.Build();

            var arguments = ParseArguments();
            // Set an optional timeout for the generator.
            var cancellationSource = arguments.MillisecondsToRun == 0 ? new CancellationTokenSource() : new CancellationTokenSource(arguments.MillisecondsToRun);
            var cancellationToken = cancellationSource.Token;
            var statistics = new Statistic[0];

            // Set the Cosmos DB connection policy.
            // TODO 3: Complete the code below to create a Cosmos DB connection policy that has a Direct Connection Mode.
            // COMPLETE THIS CODE ... var clientOptions = new CosmosClientOptions...

            var numberOfMillisecondsToLead = arguments.MillisecondsToLead;

            var taskWaitTime = 0;

            if (numberOfMillisecondsToLead > 0)
            {
                taskWaitTime = numberOfMillisecondsToLead;
            }

            var progress = new Progress<Progress>();
            progress.ProgressChanged += (sender, progressArgs) =>
            {
                foreach (var message in progressArgs.Messages)
                {
                    WriteLineInColor(message.Message, message.Color.ToConsoleColor());
                }
                statistics = progressArgs.Statistics;
            };

            WriteLineInColor("Payment Generator", ConsoleColor.White);
            Console.WriteLine("======");
            WriteLineInColor("Press Ctrl+C or Ctrl+Break to cancel.", ConsoleColor.Cyan);
            Console.WriteLine("Statistics for generated payment data will updated for every 1000 sent");
            Console.WriteLine(string.Empty);

            ThreadPool.SetMinThreads(100, 100);

            // Handle Control+C or Control+Break.
            Console.CancelKeyPress += (o, e) =>
            {
                WriteLineInColor("Stopped generator. No more events are being sent.", ConsoleColor.Yellow);
                cancellationSource.Cancel();

                // Allow the main thread to continue and exit...
                WaitHandle.Set();

                OutputStatistics(statistics);
            };

            // Get records to insert:
            var paymentRecords = GetTransactionData(Transaction.FromString);

            // Instantiate Event Hub client(s):
            var eventHubClients = new List<EventHubProducerClient>
            {
                // TODO 6: Create an Event Hub Client from a connection string, using the EventHubConnectionString value.

                // TODO 8: Create additional Event Hub clients from remaining two connection strings.
            };

            // Instantiate Cosmos DB client and start sending messages to Event Hubs and Cosmos DB:
            using (_cosmosDbClient = new CosmosClient(arguments.CosmosDbEndpointUrl,
                arguments.CosmosDbAuthorizationKey, clientOptions))
            {
                await InitializeCosmosDb();

                // Find and output the collection details, including # of RU/s.
                var container = GetContainerIfExists(DatabaseName, CollectionName);
                var throughputResponse = await container.ReadThroughputAsync(requestOptions: null, cancellationToken: cancellationToken);
                
                if (throughputResponse != null)
                {
                    WriteLineInColor($"Found container `{CollectionName}` with a current throughput of {throughputResponse.Resource.Throughput} RU/s with a max throughput of {throughputResponse.Resource.AutoscaleMaxThroughput} reads/second; {throughputResponse.Resource.AutoscaleMaxThroughput / 5} writes/second @ 1KB doc size", ConsoleColor.Green);
                    var estimatedCostPerMonth = 0.06 * throughputResponse.Resource.AutoscaleMaxThroughput;
                    var estimatedCostPerHour = estimatedCostPerMonth / (24 * 30);
                    WriteLineInColor($"The container will cost a maximum of ${estimatedCostPerHour:0.00} per hour (${estimatedCostPerMonth:0.00} per month (per write region))", ConsoleColor.Green);
                }

                // Start sending data to both Event Hubs and Cosmos DB.
                await SendData(paymentRecords, eventHubClients, 100, taskWaitTime, cancellationToken, progress, arguments.OnlyWriteToCosmosDb);
            }

            cancellationSource.Cancel();
            Console.WriteLine();
            WriteLineInColor("Done sending generated transaction data", ConsoleColor.Cyan);
            Console.WriteLine();
            Console.WriteLine();

            OutputStatistics(statistics);

            // Keep the console open.
            Console.ReadLine();
            WaitHandle.WaitOne();
        }