Spring Security using JWT Token
“A JSON Web Token (JWT), pronounced ‘jot’, is a compact URL-safe means of representing claims to be transferred between two parties. The claims in a JWT are encoded as a JSON object that is digitally signed using JSON Web Signature (JWS)”.
Download:
Please fork the complete spring project from Github.
Code Dive:
- Project Structure:
2. Maven Dependency:
3. JwtSecurityConfig contains the configuration information for JWT authentication/authorization.
4. CustomUserDetailsService.java ( Overloading loadUserByUsername)
5. JwtAuthenticationHandlerUnauthorized contains authentication failure handlers.
Returns 401 status code, if authentication exception occurs. This can be handled in the front-end side to display “Not authorized exception” or Auto Logout.
6. JwtAuthenticationFilter contains authentication and authorization info.
7. AuthController.java
Contains the sign-in handler.
7. UserPrincipal.java (Contains user-id info etc for the logged in user). Used by spring security.
8. JwtTokenProvider.java (Contains helper functions for JWT)
9. JwtConfig.java (Class having JWT specific values)
DTO:
Request & Response Data Transfer Object
Entities:
RoleEntity.java
UserEntity.java
Repository:
Usage:
hasRole(‘ADMIN’)
ANGULAR (+6) PART:
Front-end will initially send the credentials and based on the authenticity, the server will respond a JWT token. The token is thereby saved locally in localStorage, and send in the header of subsequent requests.
Login Page:
SERVICE:
MAIN parts:
- Auth Guard. Prevent routing to the page, if localStorage doesn’t contain token.
2. APP ROUTING:
3. INTERCEPTORS:
Intercepts the HTTP request/response and checks the header information etc.
4. App.module
Finally, import HTTP_INTERCEPTORS and AuthGuard.
Packaging for Angular 6+
Follow the packaging structure for angular.
ng g component components/headerng g component pages/projectRegistrationPageng g pipe pipes/objectToArray/objectToArrayng g service services/Api/Api
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