Spring Boot 3 JWT Auth Api

Last updated: 30-09-2025

• Spring Boot 3 REST API with JWT Authentication

• Working together with a Vue 3 Client

• Java 17

• Spring Boot 3

• Using settings for CORS

• Using Spring Security for protecting the url end points

• Maven as build tool

• JPA

• MySQL

• Login functionality

• GET a List of the Users

• DevTools with Hot Reload when developing

• Download or fork the source code from GitHub

• Make sure that you have a MySQL Server online

• The Web Applications is prepared to be deployed to Azure App Service using Java 17 and Tomcat 10.1

Create the file application.properties with the content below and place the file in the resources folder

spring.jpa.hibernate.ddl-auto=update

spring.datasource.url=jdbc:mysql:// the name of your mysql host / the name of your database

spring.datasource.username=your username

spring.datasource.password=your password

spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver

spring.jpa.show-sql: true

Run the Web Application locally by open a terminal in the folder of the Spring Boot Web App

• ./mvnw spring-boot:run

http://local:8080

How to do for Testing with Postman

Spring Boot 3 JWT Auth API:

Create a User in the mysql db

username: user password: persteen1967

The bcrypted value of password: persteen1967 is: $2a$10$BU4mPFHW8stXWMVH8clcZ.yZ7wl54oJq.f0Lu2HnUK6.WdooEoTZ2 and is manuel inserted in the database

POST http://localhost:8080/api/v1/login

Postman Tab "Body" - use the setting

{ "username":"user", "password":"persteen1967" }

After login in successfully 200 ok do the following:

GET http://localhost:8080/api/v1/ping

Copy the token from the response and accessToken to be used like below:

Postman Tab: "Autorization" - "Auth Type" - Select "Bearer Token" - Insert the value from the AccessToken into field "token"

Then hit Postman "send" and look at the raw body to see the message:

There should be a ok 200 with "Body": Welcome from a protected ping

Try again to check ...

Remember to delete the old accessToken by Postman Tab: "Autorization" - "Auth Type" - "token"

Now perform a login again and instead of hit ping - try to hit users

GET http://localhost:8080/api/v1/users

You will get a 403 forbidden response after a few minutes because the accessToken ( JWT ) expired

Then perform the Login again and continue :-)