Author: admin

Node.js nut-ioc usage

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nut-ioc npm package is a simple, lightweight and fast IoC Container Framework.

nut-ioc injects dependencies run-time so that developers don't need to require modules.

Developers can implement in their codes following OOP basics, principles, patterns and concepts and probably more than that 🙂

  • Separation of Concern(SoC)
  • Single Responsibility Principle(SRP)
  • Open Closed Principle
  • Dipendency Inversion(Injection) Principle(DIP)
  • Chain of Responsibility Pattern
  • Aspect Oriented Programming

you can reach github repository.

https://github.com/nodejs-projects-kenanhancer/nut-ioc

Installing nut-ioc with npm

npm i nut-ioc

Demo GitHub Repository

You can find different usages of nut-ioc framework in separate brances.

https://github.com/nodejs-projects-kenanhancer/nut-ioc-basic-demo.git

Branch list
load-dependencies-with-dependencyPath
load-dependencies-with-dependencyPath-and_dynamically
load-dependencies-with-different-loaders
load-dependencies-with-interceptors
load-dependencies-with-new-loaders-and-filters
load-dependencies-with-programatic-notation
nut-swagger-usage
Continue reading →

How to install Maven

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Downloading and Installing Maven

if you want to download Maven manually, download it from http://maven.apache.org/download.cgi

But you can download Maven programmatically as the following. So, run below script in your terminal.

wget https://downloads.apache.org/maven/maven-3/3.6.3/binaries/apache-maven-3.6.3-bin.tar.gz

tar -xzvf apache-maven*bin.tar.gz

# Fix the permissions:
# chown -R root:wheel Downloads/apache-maven*

mkdir /usr/local/apache-maven

mv apache-maven* /usr/local/apache-maven

rm apache-maven*

Setting environment variables in zsh

If you are using zsh, then run the following script in your terminal.

nano ~/.zshrc

export M2_HOME=/usr/local/apache-maven/apache-maven-3.6.3
export M2=$M2_HOME/bin
export PATH=$M2:$PATH

source ~/.zshrc

Setting environment variables in bash

nano ~/.bashrc

# add these three lines at the end of file and CTRL+X and Y and click enter :)

export M2_HOME=/usr/local/apache-maven/apache-maven-3.6.3
export M2=$M2_HOME/bin
export PATH=$M2:$PATH

source ~/.bashrc

Check Maven Version

# Verify if Maven is running
mvn -version

How to install Kafka

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Downloading

wget "https://archive.apache.org/dist/kafka/1.1.0/kafka_2.11-1.1.0.tgz"

tar -xzf kafka_2.11-1.1.0.tgz

Starting Zookeeper and kafka

bin/zookeeper-server-start.sh config/zookeeper.properties
bin/kafka-server-start.sh config/server.properties

Create topic

bin/kafka-topics.sh --create --bootstrap-server localhost:9092 --replication-factor 1 --partitions 1 --topic test

List topics

bin/kafka-topics.sh --list --bootstrap-server localhost:9092

or

bin/kafka-topics.sh --list --zookeeper localhost:2181

Send some messages to Kafka

bin/kafka-console-producer.sh --broker-list localhost:9092 --topic test

or

bin/kafka-console-producer.sh --zookeeper localhost:2181 --topic test

Consume messages from Kafka

bin/kafka-console-consumer.sh --bootstrap-server localhost:9092 --topic test --from-beginning

How to install Java

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Java Specification Versions:

Here are the major releases:

  1. Java 1.0 (January 1996) – The original version.
  2. Java 1.1 (February 1997) – Introduced several significant features, including the JavaBeans API.
  3. Java 2 (J2SE 1.2) (December 1998) – Introduced the Swing application framework.
  4. J2SE 1.3 (May 2000) – Introduced the HotSpot JVM.
  5. J2SE 1.4 (February 2002) – Introduced regular expressions, image I/O API, and more.
  6. Java SE 5 (J2SE 1.5) (September 2004) – Introduced generics, metadata annotations, enumerated types, and more.
  7. Java SE 6 (December 2006) – Introduced scripting support, JVM improvements, and more.
  8. Java SE 7 (July 2011) – Introduced the try-with-resources statement, the diamond operator, and more.
  9. Java SE 8 (March 2014) – Introduced lambdas, streams, and the java.time package.
  10. Java SE 9 (September 2017) – Introduced the module system.
  11. Java SE 10 (March 2018) – Introduced local-variable type inference (var).
  12. Java SE 11 (September 2018) – Introduced String::lines, isBlank, and other methods, plus the java.net.http HttpClient.
  13. Java SE 12 (March 2019) – Introduced switch expressions (preview) and more.
  14. Java SE 13 (September 2019) – Introduced text blocks (preview) and more enhancements.
  15. Java SE 14 (March 2020) – Introduced pattern matching for instanceof (preview) and other improvements.
  16. Java SE 15 (September 2020) – Continued the introduction and enhancement of several features.
  17. Java SE 16 (March 2021) – Introduced sealed classes (preview) and other enhancements.
  18. Java SE 17 (September 2021) – This version is an LTS (Long Term Support) release, which means it will receive updates for a longer period than the interim releases.
  19. Java SE 18 (March 2022)
  20. Java SE 19 (September 2022)
  21. Java SE 20 (March 2023)
  22. Java SE 21 (September 2023)

Java has moved to a time-driven release model, with new versions being released every six months. Not all of these are long-term support (LTS) versions. As of Java 17, the LTS versions have been Java 8, Java 11, and Java 17.

Downloading and Installing Java from OpenJDK

if you want to download OpenJDK manually, download it from https://jdk.java.net/

But you can download JDK programmatically as the following. Java SE 7, 8, 9, 10, 11, 12, 13 are included below script. So, run below script in your terminal.

# Java SE 7
wget https://download.java.net/openjdk/jdk7u75/ri/openjdk-7u75-b13-linux-x64-18_dec_2014.tar.gz

# Java SE 8
wget https://download.java.net/openjdk/jdk8u40/ri/openjdk-8u40-b25-linux-x64-10_feb_2015.tar.gz

# Java SE 9
wget https://download.java.net/java/GA/jdk9/9.0.4/binaries/openjdk-9.0.4_linux-x64_bin.tar.gz

# Java SE 10
wget https://download.java.net/java/GA/jdk10/10.0.2/19aef61b38124481863b1413dce1855f/13/openjdk-10.0.2_linux-x64_bin.tar.gz

# Java SE 11
wget https://download.java.net/java/GA/jdk11/9/GPL/openjdk-11.0.2_linux-x64_bin.tar.gz

# Java SE 12
wget https://download.java.net/java/GA/jdk12.0.2/e482c34c86bd4bf8b56c0b35558996b9/10/GPL/openjdk-12.0.2_linux-x64_bin.tar.gz

# Java SE 13
wget https://download.java.net/java/GA/jdk13/5b8a42f3905b406298b72d750b6919f6/33/GPL/openjdk-13_linux-x64_bin.tar.gz


mkdir /usr/lib/jvm


# Extract all downloaded jdk files
tar -xvzf openjdk-7u75-b13-linux-x64-18_dec_2014.tar.gz -C /usr/lib/jvm

tar -xvzf openjdk-8u40-b25-linux-x64-10_feb_2015.tar.gz -C /usr/lib/jvm

tar -xvzf openjdk-9.0.4_linux-x64_bin.tar.gz -C /usr/lib/jvm

tar -xvzf openjdk-10.0.2_linux-x64_bin.tar.gz -C /usr/lib/jvm

tar -xvzf openjdk-11.0.2_linux-x64_bin.tar.gz -C /usr/lib/jvm

tar -xvzf openjdk-12.0.2_linux-x64_bin.tar.gz -C /usr/lib/jvm

tar -xvzf openjdk-13_linux-x64_bin.tar.gz -C /usr/lib/jvm



# Remove downloaded jdk files
rm openjdk*


# Install Java and Java Compiler to Environment
update-alternatives --install /usr/bin/java java /usr/lib/jvm/java-se-7u75-ri/bin/java 1

update-alternatives --install /usr/bin/javac javac /usr/lib/jvm/java-se-7u75-ri/bin/javac 1

update-alternatives --install /usr/bin/java java /usr/lib/jvm/java-se-8u40-ri/bin/java 2

update-alternatives --install /usr/bin/javac javac /usr/lib/jvm/java-se-8u40-ri/bin/javac 2

update-alternatives --install /usr/bin/java java /usr/lib/jvm/jdk-9.0.4/bin/java 3

update-alternatives --install /usr/bin/javac javac /usr/lib/jvm/jdk-9.0.4/bin/javac 3

update-alternatives --install /usr/bin/java java /usr/lib/jvm/jdk-10.0.2/bin/java 4

update-alternatives --install /usr/bin/javac javac /usr/lib/jvm/jdk-10.0.2/bin/javac 4

update-alternatives --install /usr/bin/java java /usr/lib/jvm/jdk-11.0.2/bin/java 5

update-alternatives --install /usr/bin/javac javac /usr/lib/jvm/jdk-11.0.2/bin/javac 5

update-alternatives --install /usr/bin/java java /usr/lib/jvm/jdk-12.0.2/bin/java 6

update-alternatives --install /usr/bin/javac javac /usr/lib/jvm/jdk-12.0.2/bin/javac 6

update-alternatives --install /usr/bin/java java /usr/lib/jvm/jdk-13/bin/java 7

update-alternatives --install /usr/bin/javac javac /usr/lib/jvm/jdk-13/bin/javac 7



# Verify Java and Java Compiler Installation
# check if java command is pointing to correct path in system
update-alternatives --display java
update-alternatives --display javac

# List all environment variables
update-alternatives --get-selections
# or
update-alternatives --get-selections | grep java
# or
update-alternatives --get-selections | grep ^java

Check Java Version

# Verify if Java is running
java -version

# Verify if Java Compiler is running
javac -version

ES6 (ECMAScript 2015) Class Usage

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There are some new features in ES6(ECMAScript 2015) like the following. But, we will focus on classes.

  • JavaScript let
  • JavaScript const
  • JavaScript Arrow Functions
  • JavaScript Classes
  • Default parameter values
  • Array.find()
  • Array.findIndex()

Class Declaration Syntax

Instance properties must be defined inside of class methods.

Continue reading →

Node.js Babel 7.x different usage transpiling to ES5 and Debugging

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I already mentioned many details in the following link. So I don't want to duplicate everything in this post one more time.

You can reach github project from the following link.

https://github.com/kenanhancer/babel7-usage.git

You can reach Babel 6.x post from the following link.

Node.js Babel 6.x different usage transpiling to ES5 and Debugging

Creating Babel configuration file

.babelrc

{
  "presets": [
    "@babel/preset-env",
    "@babel/preset-react"
  ],
  "plugins": [
    "@babel/plugin-transform-runtime"
  ],
  "env": {
    "development": {
      "presets": [
        [
          "@babel/preset-react",
          {
            "development": true
          }
        ]
      ],
      "sourceMaps": true,
      "retainLines": true
    }
  }
}

Node.js nut-pipe usage

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nut-pipe npm package is an implementation of Chain of Responsibility Pattern. We can encapsulate or wrap every aspect of code in separate module or class or function, etc. So that, separated aspect modules would implement Single Responsibility Principle(SRP) and Seperation of Concern Principle(SoC) properly.

🙂 so if you want to implement OOP basics and principles, then you can use nut.pipe npm package.

This design provides to developer clean business logic code. They don't need to think about Error, Exception, Log handling business logic. Before their business logic code is called, pipeline is called and it means first middleware is triggered then first middleware will trigger next one, but no middleware knows about next middleware. Middleware should know about its business logic then should call next one.

I know too much words but developers want to see code 🙂 same code will be developed in different ways.

Code example v1

I wrote a greeting service with sayHello() and sayGoodbye() functions. They include all business logic in their body. This is not good approach definitely. Code duplications are everywhere 🙂 For example, every functions have try/catch, console.log('ENTRY: …'), console.log('SUCCESS: …'), console.log('ERROR: …'), etc. Notice that getFullName doesn't contain these business logics. So, we can't know whether it is called or not. If developer like me 🙂 doesn't write these kind of aspects(logging and exception handling is kind of aspect) then we never understand that that method is called in run-time.

Continue reading →

JavaScript Promise and Async/Await

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Asynchronous functions always return a Promise. So, I added following promise example firstly.

Promise Examples

The following three examples are doing same job. I used function statement and arrow function in Promise.

Promise with Function Declaration(Function Statement)

Promise with Arrow Function

Async Examples

Async Function Declaration(Function Statement)

Async Function Expression

Async Arrow Function

Await Examples

JavaScript – ECMAScript

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I finally decided to write this post as well. I have collected many information from different links. When I need to remember fundamentals of JavaScript, I spend too much time in google. Because many developers just focused on specific features of JavaScript. In addition to this, different naming conventions are used, even they are mentioning about same topic 🙂
So, this is very very useful post for me. I hope that it will help any developers who need this kinds of collective documentation.

Continue reading →