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Spring Boot is a Java-based framework for developing web applications that helps developers build applications easily and quickly. In this course, we will delve into how to add dependencies to the build.gradle file of a Spring Boot application.

1. Understanding Gradle

Gradle is an open-source build automation tool that allows automatic execution of build, test, and deployment processes for software projects. One of the greatest advantages of Gradle is its dependency management feature. It helps manage and easily deploy all libraries and packages used in a project.

2. Creating a Spring Boot Project

A Spring Boot project can be easily created using Spring Initializr. After completing the necessary settings in Initializr, select Gradle build and download the project. Extracting the downloaded ZIP file will provide the build.gradle file and template code.

2.1 Configuring Spring Initializr

• Project: Gradle Project
• Language: Java
• Spring Boot: Select the latest version available.
• Group: com.example
• Artifact: demo

3. Understanding the build.gradle File

The build.gradle file located in the project’s root directory is the Gradle build script. This file is used to define dependencies, plugins, build settings, and more. The basic generated Gradle script is as follows:

plugins {
    id 'org.springframework.boot' version '2.5.4'
    id 'io.spring.dependency-management' version '1.0.11.RELEASE'
    id 'java'
}

group = 'com.example'
version = '0.0.1-SNAPSHOT'
sourceCompatibility = '11'

repositories {
    mavenCentral()
}

dependencies {
    implementation 'org.springframework.boot:spring-boot-starter'
    testImplementation 'org.springframework.boot:spring-boot-starter-test'
}

4. Adding Dependencies

When using Spring Boot, you can add various libraries to extend functionality. Now, let’s learn how to add dependencies to the build.gradle.

4.1 Adding Web Application Features

To create a web application, you need to add the spring-boot-starter-web dependency. This allows you to apply the MVC pattern and establishes a foundation for building RESTful services. Add the dependency as follows:

dependencies {
    implementation 'org.springframework.boot:spring-boot-starter-web'
}

4.2 Connecting to a Database

To connect to a database with Spring Boot, you can add the spring-boot-starter-data-jpa and the database driver dependency. Set the dependencies as follows:

dependencies {
    implementation 'org.springframework.boot:spring-boot-starter-data-jpa'
    implementation 'mysql:mysql-connector-java'
}

The example above is a configuration for connecting to a MySQL database. If you are using a different database, simply add the corresponding driver as a dependency.

4.3 Setting Up OAuth2 and Security

To manage user authentication and authorization using Spring Security, add the spring-boot-starter-security dependency:

dependencies {
    implementation 'org.springframework.boot:spring-boot-starter-security'
}

4.4 Adding Other Essential Libraries

If necessary, you can add logging libraries such as Logback and Jackson to improve the performance and utility of your application:

dependencies {
    implementation 'ch.qos.logback:logback-classic'
    implementation 'com.fasterxml.jackson.core:jackson-databind'
}

5. Changes After Adding Dependencies

After adding the dependencies, Gradle automatically downloads them and sets them up for use. Enter the following command in the terminal to run the Gradle build:

./gradlew build

Once the build is complete, you will be able to use the additional libraries within your project. Now, you can implement various functionalities using them!

6. Benefits of Dependency Management

Managing dependencies with Gradle offers several advantages:

• Version Control: Specify the version of certain libraries to develop in a stable environment.
• Easy Updates: Easily update only the necessary libraries.
• Industry Standard: Using Gradle, which many developers use, facilitates collaboration.

7. Conclusion

We have learned how to add dependencies to the build.gradle file of a Spring Boot application. Dependency management is a key element for efficient development. Properly manage and utilize the necessary libraries to build a powerful web application.

8. Additional Resources

You can refer to the official documentation and various materials for Spring Boot at the following links:

• Spring Boot Official Page
• Spring Boot Documentation

In recent years, the Java-based framework Spring Boot has gained popularity in the field of backend development. Spring Boot focuses on simplifying configuration and enhancing productivity, helping developers build applications more quickly and efficiently. Additionally, advancements in cloud services have opened an era where we can easily deploy our services. In particular, AWS (Amazon Web Services) provides various cloud services and features to support the flexible operation of backend applications. This course will detail the process of developing a simple backend application using Spring Boot and deploying it to AWS.

1. Introduction to Spring Boot

Spring Boot has the motto of ‘doing a lot with minimal configuration’. Traditional Spring Framework required a lot of setup and configuration, but Spring Boot supports developers by automatically configuring these settings. As a result, we are provided with an environment where we can focus on business logic.

• Features of Spring Boot
  • Autoconfiguration: Spring Boot provides most functionalities with its default configurations.
  • Starter Dependencies: Provides necessary libraries as starter dependencies for easy use.
  • Embedded Server: Reduces deployment complexity by including servers like Tomcat and Jetty.
  • Production Ready: Spring Boot offers several features necessary for monitoring and management by default.

2. Setting Up the Spring Boot Development Environment

To develop a Spring Boot application, you must first have the Java Development Kit (JDK) installed. Also, IDEs (Integrated Development Environments) like IntelliJ IDEA, Eclipse, and VS Code are recommended. In this course, we will explain using IntelliJ IDEA as the basis.

1. Install JDK

   After installing the JDK, set the JAVA_HOME environment variable. To download the latest version of the JDK, visit the Oracle official website or OpenJDK.

2. Install IDE

   Download and install IntelliJ IDEA. After installation, complete the basic settings.

3. Create a Spring Boot Project

   Run IntelliJ IDEA, select “New Project”, and choose “Spring Initializr” to create a new Spring Boot project.

3. Configuring the Spring Boot Project

When creating a Spring Boot project, you can select the desired package structure and necessary dependencies. The commonly used dependencies are as follows:

• Spring Web: Library for developing RESTful APIs
• Spring Data JPA: Library for database integration
• H2 Database: In-memory database suitable for practice

3.1 Basic Application Configuration

After the project is created, you can open the application.properties file and add basic settings. For example, if you want to change the port number settings, you can set it as follows:

server.port=8080

3.2 Create Entity Class

In this course, we will create a simple note (or to-do) management application. Let’s create the entity class as follows:

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;

@Entity
public class Todo {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    private String title;
    private boolean completed;

    // Getter and Setter methods
}

3.3 Create Repository Interface

Use Spring Data JPA to create a repository interface that can interact with the database:

import org.springframework.data.jpa.repository.JpaRepository;

public interface TodoRepository extends JpaRepository {
}

3.4 Create Service Class

Write a service class that will handle business logic:

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;

@Service
public class TodoService {
    @Autowired
    private TodoRepository todoRepository;

    public List getAllTodos() {
        return todoRepository.findAll();
    }

    public Todo createTodo(Todo todo) {
        return todoRepository.save(todo);
    }
}

3.5 Create REST API Controller

Finally, create a controller class that provides the REST API interface for this application:

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.*;

import java.util.List;

@RestController
@RequestMapping("/api/todos")
public class TodoController {
    @Autowired
    private TodoService todoService;

    @GetMapping
    public List getAllTodos() {
        return todoService.getAllTodos();
    }

    @PostMapping
    public ResponseEntity createTodo(@RequestBody Todo todo) {
        return ResponseEntity.ok(todoService.createTodo(todo));
    }
}

4. Deploying the Service to AWS

After developing the application, you prepare to deploy it to AWS. To deploy to AWS, you need an AWS account. After creating an account, log in to the AWS Management Console.

4.1 Using Elastic Beanstalk

AWS Elastic Beanstalk is a PaaS (Platform as a Service) that simplifies the deployment of web applications and services. You can deploy your application through the following steps:

1. Create Elastic Beanstalk Environment

   Select Elastic Beanstalk in the AWS Management Console and click the “Create New Application” button. Enter the application name and description.

2. Configure Environment

   When configuring the environment, select “Web server environment” and choose “Java” as the platform. Options will be provided to upload the JAR file.

3. Create Application JAR File

   Build the project in IntelliJ IDEA to generate the JAR file. You can create it using the mvn clean package command.

4. Upload JAR File

   Return to the Elastic Beanstalk dashboard and upload the generated JAR file. Then click the “Create Environment” button to create the environment.

4.2 Check Environment URL

Once the environment is created, you can access the application through the URL provided by AWS. Enter this URL in the browser to verify that the application is functioning correctly.

4.3 Integrating with the Database

In a production environment, it is common to manage the database using RDS (Amazon Relational Database Service). Let’s explain how to set up RDS and connect the application to the database:

1. Create RDS Instance

   In the RDS dashboard, click “Create database”. Choose a database engine and complete the instance type and other settings.

2. Set Security Group

   Set the security group for the RDS instance to allow access from the application.

3. Update Application Settings

   Add the connection information for RDS to the application’s application.properties file:

   spring.datasource.url=jdbc:mysql://:/
   spring.datasource.username=
   spring.datasource.password=

5. Conclusion

In this course, we have explored how to develop and deploy a simple backend application using Spring Boot and AWS Elastic Beanstalk. Spring Boot provides a lot of convenience to developers, and AWS makes it easy to deploy developed applications. It will greatly help in building various services in real-world applications. I encourage you to continue learning more features and apply them in real business scenarios.

6. References

• Official Spring Boot Documentation
• Official AWS Elastic Beanstalk Guide
• AWS RDS Getting Started Guide

Hello! In this course, we will learn how to create an AWS (Amazon Web Services) account, which is the first step needed for Spring Boot backend development. AWS is a cloud computing service provider that offers various services and tools to help developers deploy applications quickly and easily.

1. What is AWS?

AWS is a cloud service platform provided by Amazon, and it has the following advantages:

• Reliability: Operates data centers around the world to provide high availability and disaster recovery
• Cost-effectiveness: A pay-as-you-go structure allows for flexible cost management
• Scalability: Flexibility to easily increase or decrease resources as needed
• Diverse services: Supports a variety of services including computing, storage, databases, and machine learning

2. Creating an AWS Account

The process of creating an AWS account is simple but requires a few steps. Let’s create an account following the steps below.

2.1 Access the AWS Homepage

Open a web browser and navigate to the official AWS homepage.

2.2 Select “Create an Account”

Click the “Create an Account” button at the top of the homepage. If you already have an AWS account, you will be redirected to the login page.

2.3 Enter Email Address and Password

To create a new account, enter a valid email address and set a password. The email address you enter here will be used for all communications from AWS.

2.4 Select Account Type

The account types offered by AWS are divided into personal or business accounts. Choose the account that fits your situation.

2.5 Enter Payment Information

Most AWS services offer a free tier, but you will need to enter basic payment information (credit card details). This information will be used for billing by AWS. For security reasons, AWS safely protects your card information.

2.6 Verify Identity

To verify your identity, you will need to perform phone verification. Enter the code sent to the phone number you provided to complete the verification.

2.7 Select Support Plan

AWS offers a variety of support plans. It is common for individual users or small developers to choose the free plan.

2.8 Complete Account Creation

Your account creation is now complete. Follow the confirmation email sent to the email address you entered to activate your account.

3. Navigating the AWS Console

After creating an account, you can log in to the AWS console to explore various services. The AWS console is an easy-to-use web-based dashboard that provides access to all AWS services.

3.1 Select a Service

On the main screen of the console, a variety of available services are listed. For example, you can select EC2 (Virtual Server), S3 (Storage Service), RDS (Relational Database Service), etc.

3.2 Choose a Region

AWS allows you to select a region to use the closest server. Choosing a region can reduce latency and help with disaster recovery planning.

4. Integrating Spring Boot with AWS

Now that your AWS account is created, let’s learn how to deploy a Spring Boot application to AWS. AWS provides various services suitable for hosting Spring Boot applications.

4.1 Amazon EC2

Amazon EC2 (Elastic Compute Cloud) is a virtual server service provided by AWS. By creating an EC2 instance, you can deploy and manage your Spring Boot application directly.

4.2 AWS Elastic Beanstalk

AWS Elastic Beanstalk is a platform service that helps you easily and quickly deploy applications. It supports Spring Boot and can automate deployment, server management, and monitoring.

4.3 Amazon RDS

Amazon RDS (Relational Database Service) is a service for managing relational databases. You can easily set up and operate the databases needed for your Spring Boot application.

5. Conclusion

In this course, we learned in detail about the first step for Spring Boot backend development—how to create an AWS account and the basic AWS services. Through AWS, you can easily deploy and manage your Spring Boot applications in the cloud.

In future lectures, we will cover the theory in more detail and have hands-on practice through real projects. Let’s keep working hard!

References

• AWS Documentation
• Official Spring Boot Page
• AWS Getting Started

Hello! In this tutorial, we will learn about GitHub Actions, a method to automate CI/CD (Continuous Integration/Continuous Deployment) for Spring Boot applications. GitHub Actions is a CI/CD tool that is directly integrated into GitHub repositories, making it very useful for automating software development workflows. In this article, we will cover the basic concepts of GitHub Actions, how to set it up, and how to apply it to a Spring Boot project.

1. What is GitHub Actions?

GitHub Actions is a CI/CD platform provided by GitHub that allows you to automatically perform various tasks based on events in your project repository. When code is pushed or a Pull Request (PR) is created, it can automatically handle tasks such as running tests, creating builds, and deploying by executing a specific workflow.

1.1 Features of GitHub Actions

• Flexibility: You can easily create custom workflows and actions, leveraging numerous open-source actions.
• Version Control: Each action supports versioning, allowing you to maintain a consistent environment by using specific versions of actions.
• Security: It offers various security tools and authentication features to ensure safety in production environments.

2. Getting Started

First, to use GitHub Actions, you need to create a repository on GitHub. If you already have a repository, you can simply add actions to that repository.

2.1 Create a GitHub Account

If you do not have a GitHub account, sign up here.

2.2 Create a New Repository

After logging in to GitHub, click the ‘+’ button in the top-right corner and select ‘New repository’. Set the repository name, description, visibility, etc., and click ‘Create repository’ to create a new repository.

3. Create a Simple Spring Boot Application

Now let’s develop a Spring Boot application. We will use Spring Initializr to generate the basic structure.

3.1 Using Spring Initializr

Visit the following link to set up your project: Spring Initializr. Choose the necessary dependencies and click the ‘Generate’ button to download a zip file. Now unzip this file and open it in your IDE.

3.2 Writing Basic Code

To create a simple REST API, write the following code.

@RestController
public class HelloController {
    @GetMapping("/hello")
    public String hello() {
        return "Hello, Spring Boot!";
    }
}

4. Setting Up GitHub Actions

Next, let’s set up GitHub Actions to add automated builds and test executions.

4.1 Create .github/workflows Directory

Create a .github/workflows directory in the project root. This is where the action definition files will be placed.

4.2 Create Workflow File

The workflow file is written in YAML format. Write the following code in a file named java_ci.yml.

name: Java CI

on:
  push:
    branches: [ main ]
  pull_request:
    branches: [ main ]

jobs:
  build:
    runs-on: ubuntu-latest

    steps:
    - name: Check out code
      uses: actions/checkout@v2

    - name: Set up JDK 11
      uses: actions/setup-java@v1
      with:
        java-version: '11'
        
    - name: Build with Gradle
      run: ./gradlew build

4.3 Explanation of the Workflow

In the above code, the on keywords followed by push and pull_request define that the workflow will execute when those events occur. The jobs section can define multiple tasks, each running in a specific environment. The steps section defines necessary scripts to be executed in each step.

5. Adding Tests

Now, let’s add test code to the Spring Boot application. We will add a simple unit test as follows.

@SpringBootTest
public class HelloControllerTest {

    @Autowired
    private MockMvc mockMvc;

    @Test
    public void helloShouldReturnMessage() throws Exception {
        mockMvc.perform(get("/hello"))
               .andExpect(status().isOk())
               .andExpect(content().string("Hello, Spring Boot!"));
    }
}

5.1 Updating the Test Workflow

Add the command to execute the tests in the YAML file created above.

- name: Run tests
      run: ./gradlew test

6. Commit and Push

Commit all changes and push to the remote repository.

git add .
git commit -m "Add GitHub Actions workflow"
git push origin main

6.1 Check Workflow Execution

Go to the ‘Actions’ tab of your GitHub repository to check if the workflow has executed successfully. If the build completes successfully, all settings have been configured correctly.

Conclusion

In this tutorial, we learned how to easily set up CI/CD using GitHub Actions in a Spring Boot application. Automated workflows can keep the development and deployment process efficient and consistent. Continuously leverage GitHub Actions to improve the quality of your projects!

Additional Resources

• GitHub Actions Documentation
• Spring Boot Project
• Gradle

Understanding @SpringBootApplication

Spring Boot is a framework that simplifies the development of enterprise applications. Developers often forget complex configurations or waste time on tedious tasks. To address this, Spring Boot provides various features, among which the @SpringBootApplication annotation plays the most fundamental and important role. In this tutorial, we will take a detailed look at the functionality and role of this annotation, and how it is utilized in the development of Spring Boot applications.

Definition of @SpringBootApplication

@SpringBootApplication serves as the starting point for a Spring Boot application and is a compound annotation made by combining several annotations. Internally, it includes annotations such as @Configuration, @EnableAutoConfiguration, and @ComponentScan, providing the functionality to quickly configure a Spring Boot application.

1. @Configuration

The @Configuration annotation designates the class as a Spring configuration class. It is used to define Beans and register them with the Spring container. In Spring Boot, there is no need to configure this setup separately. When the application starts, Spring Boot automatically detects the configuration and creates Beans through the Configuration class.

2. @EnableAutoConfiguration

The @EnableAutoConfiguration annotation instructs Spring Boot applications to automatically configure settings. Through this annotation, Spring Boot automatically sets up the necessary components based on the libraries and configurations included in the application’s classpath. For example, if there are database-related libraries present, Spring Boot will automatically configure the DataSource, Repository, and related Beans suitable for those libraries.

3. @ComponentScan

The @ComponentScan annotation directs Spring to scan for components in specified packages. This annotation allows the application to automatically search for and register various components, services, and repositories. By default, it is set to automatically scan the package where the class declaring @SpringBootApplication is located, as well as its sub-packages.

Example Code

The code below is an example of a simple Spring Boot application.

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class MySpringBootApplication {
    public static void main(String[] args) {
        SpringApplication.run(MySpringBootApplication.class, args);
    }
}

Running the Application

The above class defines a Spring Boot application named MySpringBootApplication. It calls the SpringApplication.run() method in the main method to run the application. During this process, all configurations applied by @SpringBootApplication are automatically loaded.

Additional Features of Spring Boot

Spring Boot offers various additional features based on @SpringBootApplication. These include profiles, external configuration files (application.properties or application.yml), database migration, logging, monitoring, testing capabilities, and more.

Profiles

Spring Boot provides the profile feature to manage settings that vary depending on the environment. This allows easy management of different configurations for development, testing, and production environments. For example, using an H2 database in a local environment and MySQL in production.

External Configuration Files

Spring Boot helps manage application settings externally through application.properties or application.yml files. Various configurations can be defined in these files, and environment variables can be used to manage sensitive information.

Database Migration

Spring Boot easily integrates with database migration tools like Flyway or Liquibase. This allows for managing database schemas and automatically performing necessary migrations in response to application version changes.

Logging

Spring Boot uses SLF4J and Logback as the default logging framework. Logging configuration can be adjusted with simple properties, and log levels and output formats can be modified as needed.

Monitoring

Spring Boot Actuator provides tools for monitoring and managing the application’s state. This allows for easy health checks, metrics, traffic monitoring, and more.

Testing

Spring Boot facilitates easy setup of tests using JUnit and Mockito. The @SpringBootTest annotation can be used to create integration tests to verify that each component operates correctly.

Conclusion

Spring Boot is a powerful tool for developers. The @SpringBootApplication annotation is the simplest way to configure these features. By utilizing Spring Boot with various additional functionalities, productivity in backend development can be greatly enhanced.

References

• Spring Boot Official Documentation
• Guide to Spring Boot and OAuth2
• Spring Boot Reference Documentation