Category: tutorials

Docker for Developers crash course

Who is addressed to

This tutorial is aimed to programmers that what to automate the infrastructure surrounding their application. It will contain practical examples of how to improve your application with Docker infrastructure.

The class will be taken by Andrei Ignat, former C# MVP for 6 years, https://forums.asp.net moderator and OpenSource contributor( you can find his AspNetCoreImageTagHelper mentioned on https://github.com/aspnet/Mvc ). More details at his blog at http://msprogrammer.serviciipeweb.ro .

What it contains

Day 1 –Docker basics

Docker starters

– images

– containers

Examples:

Docker for Databases – SqlServer, Mongo

Docker for messaging – RabbitMq

Docker for Applications – .NET Core, Angular

Docker CLI commands

Docker File

Docker-Compose File and CLI for orchestration

Day 2 –Docker

Docker for CI / CD

– automated reproducible building

– automated reproducible testing

Visual Studio Code and Docker

Architecture of Applications with Docker

5 Minutes .NET–Memory Cache

At https://youtu.be/BL5yo_p7x-E you can find the new video about caching in .NET with Memory Cache.

The code is:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.Caching;
using System.Text;
using System.Threading.Tasks;

namespace MemoryCacheNet
{
    public static class GlobalData
    {
        static object lockMe = new object();

        public static List<string> CountryList()
        {
            string key = "countries";
            var data = MemoryCache.Default.Get(key) as List<string>;
            if(data == null)
            {
                lock (lockMe)
                {
                    data = MemoryCache.Default.Get(key) as List<string>;
                    if(data != null)
                    {
                        return data ;
                    }
                    data = CountryListFromDatabase();
                    var duration = DateTimeOffset.UtcNow.AddSeconds(5);
                    MemoryCache.Default.AddOrGetExisting(key,data,duration);
                   

                }
            }
            return data;
        }
        static List<string> CountryListFromDatabase()
        {
            Console.WriteLine("obtaining data from database");
            return new List<string>()
            {
                "Romania",
                "India",
                "USA"
                // add your country 😉
            };
        }
    }
}

and using from Console:

using MemoryCacheNet;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading;
using System.Threading.Tasks;

namespace MemoryCacheDOS
{
    class Program
    {
        static void Main(string[] args)
        {
            var data = GlobalData.CountryList();
            Console.WriteLine(data.Count);

            Console.WriteLine("waiting 1 sec");
            Thread.Sleep(1000);
            data = GlobalData.CountryList();
            Console.WriteLine(data.Count);

            Console.WriteLine("waiting 5 sec");
            Thread.Sleep(5000);
            data = GlobalData.CountryList();
            Console.WriteLine(data.Count);

        }
    }
}