DEV Community: aburra12

What am I currently reading 📚 📚

aburra12 — Thu, 24 Feb 2022 08:15:52 +0000

https://noidea.dog/glue - A coworker shared this article and it is amazing to understand how much important glue work is for a project and what it means for a Senior Engineer to be that glue.

https://livebook.manning.com/book/the-art-of-unit-testing-third-edition/welcome/v-6/1

Powerful insights from Chapter 1 :
So, what’s a “good” unit test?

Unit tests should run quickly and be consistent in its results (it always returns the same result if you don’t change anything between runs).

should have full control of the code under test.
should be fully isolated (runs independently of other tests).
should run in memory without requiring system files, networks, databases.
should be as synchronous and linear as possible when it makes sense. (no parallel threads if we can help it)

Wait... Synchronous??? What about asyncs/awaits..

From a unit testing point of view, we should find a way to make the processes happening through a single path in a unit of work, from entry point to exit point, as synchronous as possible. That might mean triggering callbacks directly from the test, or it might mean faking the time in the test to the point where the test does not need to wait for any async code to finish executing, unless there’s no other choice (at that point it might not be a unit test, but the situations can vary quite a bit).

My prep towards AWS Solutions Architect certification

aburra12 — Thu, 24 Feb 2022 07:58:03 +0000

First things first : 1. I finally made up my mind to take this certification. have been putting it off since last October..phew

Purchased course material from Udemy - costed about $40( got a good deal) Here's the link to purchase - https://www.udemy.com/course/aws-certified-solutions-architect-associate-saa-c02/
There are a total of 30 Sections with each section divided into little pieces for easy digestion ( love that!)

Course starts off with AWS Cloud Overview - Regions, Tour of the Console & Services in AWS

Major topics

IAM & AWS CLI
EC2 Fundamentals
EC2 Solutions Architect Associate Level
EC2 Instance Storage
High Availability & Scalability - ELB & ASG
RDS + Aurora + ElastiCache
Route 53
Amazon S3 & Athena
AWS SDK, IAM Roles & Policies
CloudFront & AWS Global Accelerator
AWS Storage Extras
SQS, SNS, Kinesis, Active MQ
Containers on AWS : ECS, Fargate, ECR &EKS
and many more...

Task Vs Thread ( C#)

aburra12 — Thu, 24 Feb 2022 07:39:20 +0000

Notes gathered from different sources:

System threads are nothing but resources for tasks

Key differences between Task and Thread

Usually you hear Task is a higher level concept than thread... and that's what this phrase means:

You can't use Abort/ThreadAbortedException, you should support cancel event in your "business code" periodically testing token.IsCancellationRequested flag (also avoid long or timeoutless connections e.g. to db, otherwise you will never get a chance to test this flag). By the similar reason Thread.Sleep(delay) call should be replaced with Task.Delay(delay, token) call (passing token inside to have possibility to interrupt delay)

Code sample for Cancellation Tokens in my github repo : https://github.com/aburra12/TaskCancellation

There are no thread's Suspend and Resume methods functionality with tasks. Instance of task can't be reused either.

But you get two new tools:

a) continuations

// continuation with ContinueWhenAll - execute the delegate, when ALL
// tasks[] had been finished; other option is ContinueWhenAny

Task.Factory.ContinueWhenAll( 
   tasks,
   () => {
       int answer = tasks[0].Result + tasks[1].Result;
       Console.WriteLine("The answer is {0}", answer);
   }
);

b) nested/child tasks
//StartNew - starts task immediately, parent ends whith child

var parent = Task.Factory.StartNew
(() => {
          var child = Task.Factory.StartNew(() =>
         {
         //...
         });
      },  
      TaskCreationOptions.AttachedToParent
);

The task can return a result. There is no direct mechanism to return the result from a thread.
A task can have multiple processes happening at the same time. Threads can only have one task running at a time.
A new Thread()is not dealing with Thread pool thread, whereas Task does use thread pool thread.

How to create a Task

static void Main(string[] args) {  
    Task < string > obTask = Task.Run(() => (  
        return“ Hello”));  
    Console.WriteLine(obTask.result);  
}

How to create a Thread

static void Main(string[] args) {  
    Thread thread = new Thread(new ThreadStart(getMyName));  
    thread.Start();  
}  
public void getMyName() {}