Hi people!!

Today, I will teach you how to create the calculator with basic functions.

But before starting, is important to refer to the CRUD definition.

The CRUD defintion are the acronyms for Create, Read, Update and Delete and these are the four basic operations used in relational databases.

In the ISO / SQL standard, this is the mapped abbreviation CRUD:

• Create — INSERT
• Read — SELECT
• Update — UPDATE
• Delete — DELETE

So, let’s put this into practice!!

1st step: Create a directory for the project

mkdir calculator
cd calculator

2nd step: Start the project

npm init

Remember that at the end of this step a package.json file will be created.

3rd step: Installing required packages

npm…

Agora que concluímos a instalação do Hadoop podemos prosseguir a instalação do Apache Spark com dois slaves, tal como no tutorial anterior no qual instalamos o Apache Hadoop faremos a nossa instalação por passos simples para facilitar o processo.

Introdução

O Spark é um framework open-source para processamento de Big Data construído com foco em velocidade, facilidade de uso e análises sofisticadas.

O Spark permite que aplicações em clusters Hadoop executem até 100 vezes mais rápido em memória e até 10 vezes mais rápido em disco, desenvolver rapidamente aplicações em Java, Scala ou Python. …

Hi people!!

In this tutorial, we will install and configure Hadoop on Ubuntu with single-node only.

But before we start, we need the following requirements:

• Ubuntu 18.04 (Can be used on a virtualized machine in VirtualBox);
• Java installed;

After installing ubuntu, to make sure you have Java installed, use the following command:

java -version

If not, use the following commands to install:

sudo apt-get install default-jre
sudo apt-get install default-jdk

Now you already have Java installed

Neste tutorial, iremos mostrar como foi implementada a nossa API que é sobre o registo de Take Away. A mesma foi desenvolvida em JavaScript complementando ainda com mongoDB Atlas e o SwaggerUI.

Vamos então indicar todos os passos precisos para a criação desta API

1º Passo: Criação do Projeto

2º Passo: Criação da Base de Dados

3º Passo: Desenvolvimento da API

4º Passo: Disponibilizar a API online

1º passo: Criação do Projeto

Usando a linha de comandos, criámos os diretórios precisos juntamente com os ficheiros necessários

• Criação do projeto juntamente com a respetiva instalação:

mkdir api-TakeAway
cd api-TakeAway
npm init

• Preencher a description e o author (opcional):

Hi people!!

Today, I will explain the Distributed Systems Concept, concretely:

• What it is?
• Some examples of the same
• The features
• Advantages and disadvantages of a Distributed System

What is a Distributed System?

In general, a Distributed System is a system with several components that is found on different machines so that it is connected through a data network and that presents itself as a single system for users.

Examples of Distributed System

In the current world, we find several examples of distributed systems, with special emphasis:

• Telecommunication networks;
• Network applications;
• Online games;
• Etc.

The key features of a Distributed System

• Openess: In order for the systems to “talk” between then, it is very important that…

Hi people!!

In this tutorial, you will learn how to make a calculator API with elementary arithmetic operations, using Swagger.

Swagger is an interface description language for describing RESTful APIs expressed using JSON and is used in conjunction with a set of Open Source software tools to design, build, document and use RESTful web services.

So let’s start the tutorial!!

1st step: Open the command line and use the following commands to create the project.

mkdir calculatorSwagger
cd calculatorSwagger
npm init

After that, we will indicate the requested parameters.

Hi people!!

In this tutorial, I will show you how to build an API using the JWT authentication in LoopBack 4.

1st step: Install node.js the Todo example and install the JWT authentication extension

npm init
lb4 example todo
cd loopback4-example-todo
npm i --save @loopback/authentication @loopback/authentication-jwt

2nd step: Create the Controller for login

Hi people!!

In this tutorial, I will show you how to build an API using node.js and, especially, LoopBack 4.

To do this, you only need the PC’s command line.

1st step: Install node.js and LoopBack 4

npm init
npm i -g @loopback/cli

2nd step: Create the app scanffolding