BlockBlob Generator module for testing IoT Edge Blob storage module

gistfile1.txt

using System;
using System.IO;
using System.Runtime.Loader;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using Microsoft.Azure.Devices.Client;
using Microsoft.Azure.Devices.Client.Transport.Mqtt;
using Microsoft.WindowsAzure.Storage;
using Microsoft.WindowsAzure.Storage.Blob;
using System.Collections.Generic;
using System.Linq;

class Program
{
	private static  MemoryStream _stream; 
	private static StreamWriter  _writer;
	private static string _currentFileName; 
	private const int _interval = 5000;
	private static UInt16 _counter;
	private static CloudBlobContainer _container;

	static void Main(string[] args)
	{
		Init().Wait();
		var cts = new CancellationTokenSource();
		AssemblyLoadContext.Default.Unloading += (ctx) => cts.Cancel();
		Console.CancelKeyPress += (sender, cpe) => cts.Cancel();
		WhenCancelled(cts.Token).Wait();
	}

	public static Task WhenCancelled(CancellationToken cancellationToken)
	{
		var tcs = new TaskCompletionSource<bool>();
		cancellationToken.Register(s => ((TaskCompletionSource<bool>)s).SetResult(true), tcs);
		return tcs.Task;
	}

	static async Task Init()
	{
		MqttTransportSettings mqttSetting = new MqttTransportSettings(TransportType.Mqtt_Tcp_Only);
		ITransportSettings[] settings = { mqttSetting };
		ModuleClient ioTHubModuleClient = await ModuleClient.CreateFromEnvironmentAsync(settings);
		await ioTHubModuleClient.OpenAsync();
		Console.WriteLine("IoT Hub module Generator client initialized.");

		// Blob container construction and thread start
		var account = CloudStorageAccount.Parse(
			"DefaultEndpointsProtocol=https;BlobEndpoint=http://blob:11002/blobaccount;AccountName=blobaccount;AccountKey=[local storage key]");
		var client = account.CreateCloudBlobClient();
		_container = client.GetContainerReference("updatedblockblobcontainer");
		_container.CreateIfNotExistsAsync().Wait();
		var thread = new Thread(() => ThreadBody(ioTHubModuleClient));
		thread.Start();
	}

	private static void ThreadBody(object userContext)
	{
		while (true)
		{
			WriteBlockBlob().GetAwaiter().GetResult();

			Thread.Sleep(_interval);
		}
	}

	private static async Task WriteBlockBlob()
	{
		_counter += 1;

		var now = DateTime.UtcNow;
		var filename = "File" + now.ToString("yyyyMMddHHmm");
		var blob = _container.GetBlockBlobReference(filename);

		var blockList = new List<string>();

		if (blob.ExistsAsync().Result)
		{
			IEnumerable<ListBlockItem> existingBlockList = await blob.DownloadBlockListAsync();
			blockList.AddRange(existingBlockList.Select(a => a.Name));
		}

		string blockId = Convert.ToBase64String(ASCIIEncoding.ASCII.GetBytes(now.ToString()));

		if (filename != _currentFileName)
		{
			if (!string.IsNullOrEmpty( _currentFileName))
			{
				_writer.Close();
				_stream.Close();
			}

			_stream = new MemoryStream();
			_writer = new StreamWriter(_stream);
			_currentFileName = filename; 
		}

		_writer.Write($"We add a test for counter {_counter} at {now:yyyyMMddHHmmss}");
		_writer.Flush();
		_stream.Position = 0;

		await blob.PutBlockAsync(blockId, _stream, null);
		blockList.Add(blockId);
		await blob.PutBlockListAsync(blockList.ToArray());

		Console.WriteLine($"Block {_counter} written for file {filename} at {now:yyyy-MM-dd HH:mm:ss}");
	}      
}