.NET

Azure DevOps–Community Launch-Letterkenny (08-January’ 2019)

December 21, 2018 .NET, .NET Core, .NET Framework, Announcements, Azure, Azure DevOps, Azure DevOps Server, Azure DevOps Services, Community, LKMUG, Microsoft No comments

Inviting you all to Azure DevOps Community Launch in Letterkenny on 08th Jan 2019. Few months back Microsoft Visual Studio Team Services has been rebranded as Azure DevOps.

Azure DevOps is now a suite of separate but integrated services for managing software projects, source control, build and release management and automation testing to enhance your productivity and team performance in whatever development and deployment environment you choose.

Martin Woodward: The Principal GPM for @AzureDevOps and Vice-President of the .NET Foundation would be joining us in Letterkenny for this event.

To know more about Martin Woodward:

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What we’ll cover:
 Introduction to Azure DevOps
 Azure Pipelines: Fully managed CI/CD platform that works with any language, platform, and cloud
 Azure Repos: Source code repositories (Git/TFVC)
 Azure Test Plans: Manual and Automated Testing
 Azure Boards: Plan, track, and discuss work across your teams
 Azure Artifacts: Package management

Additionally, We’ll also cover how to use Azure Pipelines for Continuous builds with your GitHub projects.

If you are interested to learn how to plan smarter, collaborate better and ship faster, sign up now and RSVP/Share it: https://www.meetup.com/lk-mug/events/255764767/ 

Please follow us on:

C# 8.0 New Feature–Interface Default Implementation for Methods

December 1, 2018 .NET, .NET 4.8, .NET Core, .NET Core 3.0, ASP.NET, Microsoft, Visual Studio 2017, VisualStudio, VS2017 No comments

With upcoming C# 8.0, there is an interesting feature called default implementation body for methods within an interface definition. That means if you have few methods signatures defined and you want make implementation classes to implement these methods optionally (remember, previously all interface methods needs to be implemented in implementation classes) , with C# 8.0, you can define methods to follow default implementation body, if it not explicitly implemented by implementation classes of the same interface.

When will we get C# 8.0?

C# 8.0 will be released along .NET Core 3.0, in upcoming months. Currently preview 1 version is available to try out.

Get Started:

1.) First of all, download and install Preview 1 of .NET Core 3.0 and Preview 1 of Visual Studio 2019.

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2.) Launch Visual Studio 2019 Preview, Create a new project, and select “Console App (.NET Core)” as the project type.

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3.) Once the project is up and running, change its target framework to .NET Core 3.0 (right click the project in Solution Explorer, select Properties and use the drop down menu on the Application tab).

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Here is how it can be implemented:

using System;

namespace CSharp8Demo
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Hello World!");

            IVehicle bmw = new Bmw();
            bmw.DefaultMessage();

            IVehicle audi = new Audi();
            audi.DefaultMessage(); 
        }
    }


    interface IVehicle
    {
        //default implementation 
        void DisplayMessage();

        void DefaultMessage() { Console.WriteLine("I am  inside default method in the interface!");} 
      
    }

    public class Bmw : IVehicle
    {
        public void DisplayMessage()
        {
            Console.WriteLine("I am BMW!!!");
        }
    }

    public class Audi : IVehicle
    {
        public void DisplayMessage()
        {
            Console.WriteLine("I am AUDI!!!");
        }
        public void DefaultMessage() => Console.WriteLine("I am  inside audi class!");
    }
}

Visual Studio 2017–Version 15.9.0 released

November 13, 2018 .NET, .NET 4.8, .NET Core, .NET Core 2.0, .NET Core 2.1, .NET Core 2.2, .NET Core 3.0, .NET Framework, ASP.NET, ASP.NET Core 2.1, C#.NET, JavaScript, Microsoft, Razor, SignalR, TypeScript No comments

Microsoft has today released Visual Studio 2017 – Update 15.9.0 with lots of bug fixed and improvements to the IDE for stability and performance.

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Release Notes: Visual Studio 2017 version 15.9 Minor Release

Download the latest update from: visualstudio.com/downloads

Latest News: There is a new service update released on November 15, 2018 — Visual Studio 2017 version 15.9.1 Servicing Update

Useful Reads: 

Azure Cosmos DB – TTL (Time to Live) – Reference Usecase

October 9, 2018 .NET, .NET Core, .NET Framework, Analytics, Architecture, Azure, Azure, Azure Cosmos DB, Azure Functions, Azure IoT Suite, Cloud Computing, Cold Path Analytics, CosmosDB, Emerging Technologies, Hot Path Analytics, Intelligent Cloud, Intelligent Edge, IoT Edge, IoT Hub, Microsoft, Realtime Analytics, Visual Studio 2017, VisualStudio, VS2017, Windows No comments

TTL capability within Azure Cosmos DB is a live saver, as it would take necessary steps to purge redudent data based on the configurations you may. 

Let us think in terms of an Industrial IoT scenario, devices can produce vast amounts of telemetry information, logs and user session information that is only useful until we operate on them and take action on them, to be specific up to finate period of time. Once that data becomes surplus, we need an application logic that purges these old records.

With the “Time to Live” or TTL, Microsoft Cosmos DB provides an ability to have your documents automatically purged from database storage after a certian period if time(which you configured)

  • This TTL by default can be set on a document collection level and later can be overridden on a per document basis.
  • Once the TTL is set, Cosmos DB service will automatically remove the documents when its lifetime is over.
  • Inorder to track TTL, Cosmos DB uses an offset field to check when it was last modified.  This field is identifiable as “_ts”, which exists in every document you create.  Basically it is a UNIX epoch timestamp. This field is updated everytime when the document is modified. [Ref: Picture1]

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[Picture1]

Enabling TTL on Cosmos DB Collection:

You can enable TTL on a Cosmos DB collection simply by using Azure Portal –> Cosmos DB collection setting for existing or during creation of  a new collection)

TTL value needs to be set in seconds – if you need 90 days => 60 sec * 60 min * 24 hour * 90 days = 7776000 seconds

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[Picture2]

Below is a one of the reference architecture in which Cosmos DB – TTL would be essentially useful and viable to any Iot business case:

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[Picture3]

Hope that was helpful to get some understanding. For more references visit:  Cosmos DB Documentation

Azure Cosmos DB–Multi Master

October 8, 2018 .NET, .NET Core, .NET Framework, ASP.NET, Azure, Azure CLI, Azure Cosmos DB, CosmosDB, Data Consistancy, Data Integrity, Microsoft, Multi-master, Performance, Reliability, Resilliancy, Scalability, Scale Up No comments

During the Ignite 2018, Microsoft has announced the general availability of Multi-Master feature being introduced to Azure Cosmos DB to provide more control into data redundancy and elastic scalability for your data from different regions with multiple writes and read instances.

What is Multi-Master essentially?

Multi-master is a capability that provided as part of Cosmos DB, that would provide you multiple write regions and provides an option to handle conflict resolution automatically through different options provided by the platform. Most of the major scenarios you would encounter the conflict can be resolved with these simple configurations.

A sample diagram depicting a use case of load balanced web app writing to respective regional master:-

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With multi-master, Azure Cosmos DB delivers a single digit millisecond write latency at the 99th percentile anywhere in the world, and now offers 99.999 percent write availability (in addition to 99.999 percent read availability) backed by the industry-leading SLAs.

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Wow! That’s an amazing performance Cosmos DB guarantees to provide so that your mission-critical systems will have zero downtime, if they start using Cosmos DB.

 

How to Enabled Multi-Master support in your Cosmos DB solutions?

Currently multi-master can only be enabled for new Cosmos DB instances using “Enable Multi-Master” option in Azure Portal or through PowerShell or ARM templates or through SDK.

These options are detailed below with necessary examples:

1.) Azure Portal – Enable Multi-region writes and Enable geo-redundancy

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2.) Azure CLI 
Set the “enable-multiple-write-locations” parameter to “true”

az cosmosdb create \
   –-name "thingx-cosmosdb-dev" \
   --resource-group "consmosify-dev" \
   --default-consistency-level "Session" \
   --enable-automatic-failover "true" \
   --locations "EastUS=0" "WestUS=1" \
   --enable-multiple-write-locations true \

3.) AzureRM PowerShell
In AzureRM PowerShell cmdlet – Set enableMultipleWriteLocations parameter to “true”

$locations = @(@{"locationName"="East US"; "failoverPriority"=0},
             @{"locationName"="West US"; "failoverPriority"=1})

$iprangefilter = ""

$consistencyPolicy = @{"defaultConsistencyLevel"="Session";
                       "maxIntervalInSeconds"= "10";
                       "maxStalenessPrefix"="200"}

$CosmosDBProperties = @{"databaseAccountOfferType"="Standard";
                        "locations"=$locations;
                        "consistencyPolicy"=$consistencyPolicy;
                        "ipRangeFilter"=$iprangefilter;
                        "enableMultipleWriteLocations"="true"}

New-AzureRmResource -ResourceType "Microsoft.DocumentDb/databaseAccounts" `
  -ApiVersion "2015-04-08" `
  -ResourceGroupName "consmosify-dev" `
  -Location "East US" `
  -Name "thingx-cosmosdb-dev" `
  -Properties $CosmosDBProperties

4.) Through CosmosDB SDK
Setting connection policy in DocumentDBClient and set UseMultipleWriteLocations to true.

ConnectionPolicy policy = new ConnectionPolicy
{
   ConnectionMode = ConnectionMode.Direct,
   ConnectionProtocol = Protocol.Tcp,
   UseMultipleWriteLocations = true,
};
policy.PreferredLocations.Add("East US");
policy.PreferredLocations.Add("West US");
policy.PreferredLocations.Add("West Europe");
policy.PreferredLocations.Add("North Europe");
policy.PreferredLocations.Add("Southeast Asia");
policy.PreferredLocations.Add("Japan East");
policy.PreferredLocations.Add("Japan West");

Azure Cosmos DB multi-master configuration is the game changes that really makes it a true global scale database with automatic conflict resolution capabilities for data synchronization and consistancy.

In my later sessions I will write examples to cover how conflict resolutions can be configured and used in realtime scenarios.

Useful Refs:

Azure Cosmos DB – 429 Too Many Requests

October 6, 2018 .NET, Azure, CosmosDB, Document DB, Microsoft, Performance, Reliability, Resilliancy, Scalability, Visual Studio 2017, VisualStudio, VS2017 No comments

Recently while I was doing Performance Testing in one of the APIs interacting with Cosmos DB, I encountered a problem as Azure Cosmos DB API’s started returning Http Code 429.  Http Status Code 429 indicates that too many request been received or request rate is very large. This error would happen when we have concurrent users trying to write or read from same cosmos db collection.

Following diagram covers the architecture of the performance test I am performing:

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Based on analysis it found out to be the Throttling happening from Azure Cosmos DB, as we make requests that may use more than provisioned Request Units(RU) per second. We were using default Cosmos DB configuration for a fixed collection of 1000 RU’s per second which is sufficient enough for a 500 reads and 100 writes for a 1 kb file. You can refer more about Request Units from Azure Docs.

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Solution(s):

1. Now first logical step we can do is to get rid off this error by increasing the Throughput for the collection.  I am going to increase to 10000 RU/s maximum allocatable for a Storage Capacity: Fixed.   This should ideally improve the Throughput for 250 or more virtual users hitting.

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2. Second logical step is to improve the code: Improve the connection parameters in the Document DB SDK –> DocumentDbClient. For this I referred to the Microsoft Docs: Performance tips for Azure Cosmos DB and .NET

Providing optimum values to the following Properties in RetryOption class   to be passed as parameter to Connection Policy.

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In my case I provided a value of 30 to give ultimate results:

new RetryOptions() { MaxRetryAttemptsOnThrottledRequests = 30, MaxRetryWaitTimeInSeconds = 30  }

That should resolve most of the 429 issues when dealing with Cosmos DB SDK