Spring Boot - Modularizing project into modules and re-use

While working with microservices, there will be many small modules in your systems, they calls each others, for me it would be great if we can share at least the data transfer classes. It will save time on development

Here is the structure of my example

In the example, I created a rest-module-example module, it is the main module which separated into 2 modules ( dto.jar and app.jar )

The rest-module-consumer-example will include the dto.jar ( by Maven or Gradle ) , so It will be easy to consume the REST API

You can find details implementation in the repos below:

rest-module-example: https://github.com/vanduc1102/spring-boot-examples/tree/master/module-rest-example

rest-module-consumer-example: https://github.com/vanduc1102/spring-boot-examples/tree/master/module-rest-consumer-example

Spring Boot override Bootstrap properties

1. Bootstrap properties file is inside the packaged jar

This is not a useful case to manage the bootstrap properties or application properties, the reason is you have to rebuild your application again if made any change to the properties

You should have properties file name following the format bootstrap-{profile}.yml ( or .properties variants)

2. Bootstrap properties is outside of the packaged jar.

I prefer this case to manage properties, we don’t need to rebuild the application again if we made change to properties also we can manage our properties better with VCS like git.

Let assume that we have a configuration file outside of packaged jar.

In order to load the file, we need to change the bootstrap properties location by override the spring.cloud.bootstrap.location attribute.

With this approach we can easily override the bootstrap properties.

Spring Boot Sleuth and ZipKin

This post is my implementation of the post here: https://reflectoring.io/tracing-with-spring-cloud-sleuth/

Although the post already included the source code, but it is still pretty hard for me to start

So I created this post to help me to remember how to make Slueth and Zipkin work.

Spring Cloud Sleuth

will add traceId and spanId to logger

<dependency>
  <groupId>org.springframework.cloud</groupId>
  <artifactId>spring-cloud-starter-sleuth</artifactId>
  <version>${spring-cloud.version}</version>
</dependency>

Analyze Traces with ZipKin

Logger collector and analytics

<dependency>
  <groupId>org.springframework.cloud</groupId>
  <artifactId>spring-cloud-starter-zipkin</artifactId>
  <version>${spring-cloud.version}</version>
</dependency>

spring.sleuth.sampler.percentage=1.0

Is percentage of sampler, the default value is 0.1 ( 10%) that means you only take 10% of request to sampler

Change to 1.0 ( 100% ) to sample all of request.

Repo URL: https://github.com/vanduc1102/tutorials/tree/master/spring-sleuth

 

Spring Boot 2 - REST template project

Recently, I have a chance to work with Spring Boot, it was pretty hard for me to create Spring project without template that is ready for development. So I created a template to help me save time for next projects.

What are included in this boilerplate:

• Java code format: https://github.com/google/google-java-format


• Maven wrapper version 3.5.4


• Spring Boot version 2.0.5 : https://mvnrepository.com/artifact/org.springframework.boot/spring-boot/2.0.5.RELEASE


• Lombox https://mvnrepository.com/artifact/org.projectlombok/lombok/1.18.2


• Swagger-UI https://mvnrepository.com/artifact/io.springfox/springfox-swagger-ui/2.9.2


• Testing frameworks
  
  
  
  • Spring starter tester: https://docs.spring.io/spring-boot/docs/current/reference/html/boot-features-testing.html
  
  
  • PowerMock: https://github.com/powermock/powermock
  
  
  • Podam: https://mtedone.github.io/podam/


• Code Jacoco: https://www.jacoco.org/jacoco/trunk/doc/
  
  
  
  • Running command: 

    ./mvnw clean jacoco:prepare-agent install
    

Github Repo: https://github.com/vanduc1102/spring-boot-examples/tree/master/spring-boot-2-rest-service-basic

Install Eclipse Window

Before start install Eclipse, you should check if your PC had installed Java(JDK) here : https://aduckdev.wordpress.com/2018/08/04/how-to-install-jdk-and-setup-java_home-in-windows-10/


Download Eclipse

Open: http://www.eclipse.org/downloads/download.php




Open the downloaded file to start installation:





Choose IDE for Java Developer:



Choose a folder for installation, we will use default value here.



Click Next to install, after the installation finished, click Launch to launch Eclipse



Choose workspace folder. You can use the default also.



And here is your Eclipse.

How to setup ANDROID_HOME

In order to setup ANDROID_HOME, you need to have Android SDK installed on your PC

Checkout this link: https://developer.android.com/studio/ you can find both Android Studio and Android SDK



What is Android SDK: it is a bundled of command line tools help you to develop an Android application, it is shipped inside Android Studio

This tutorial show you how to setup ANDROID_HOME variable after you installed Android Studio

1.To find location of Android SDK on your PC. Open Android Studio

Open File --> Settings, type SDK and you will see the location of SDK on your PC, here is: C:\Users\DucNGUYEN\AppData\Local\Android\Sdk 

2. Setup ANDROID_HOME environment

Open Advanced System Settings: hit Window key and type advanced system

Choose Environment variable



Add the new variable ADROID_HOME:


Click OK to save variable and exit the Advanced System Settings.

3. Check the variable installed

Open new Command Prompt window and type echo %ANDROID_HOME% to check



DONE

Install NodeJS on Windows

Step 1. Download NodeJS

Open: https://nodejs.org/en/download/

Download 64bit version

Step 2. Install the downloaded file

Install downloaded msi file

Right click on download msi file[/caption]


Click on Next, Next to install as normal application


Installation successfully

Step 3. Verify the installation

Open Command Prompt to check.

Congratulations