10738 - Implement Authentication controller

[njtalba5127]

Timestamp: (10738) / 11632

[njtalba5127]

create new java class file called "AuthenticationController.java" inside the controllers package.

AuthenticationController.java

package com.nellyxinwei.backend.controllers;

import org.springframework.http.ResponseEntity;
import org.springframework.security.authentication.AuthenticationManager;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import com.nellyxinwei.backend.dto.AuthenticationRequest;

import lombok.RequiredArgsConstructor;

@RestController
@RequestMapping("/api/v1/auth")
@RequiredArgsConstructor
public class AuthenticationController {

  private final AuthenticationManager authenticationManager;

  public ResponseEntity<String> authenticate(
      @RequestBody AuthenticationRequest request) {
    authenticationManager.authenticate(
        new UsernamePasswordAuthenticationToken(request.getEmail(), request.getPassword()));
  }
}

[njtalba5127]

create a new package called "dto", and in it create a new java class file called "AuthenticationRequest.java"

AuthenticationRequest.java:

package com.nellyxinwei.backend.dto;

import lombok.Getter;
import lombok.NoArgsConstructor;
import lombok.Setter;

@Getter
@Setter
@NoArgsConstructor
public class AuthenticationRequest {
  public String email;
  public String password;
}

[njtalba5127]

.
└── backend
    ├── HELP.md
    ├── mvnw
    ├── mvnw.cmd
    ├── pom.xml
    ├── src
    │   ├── main
    │   │   ├── java
    │   │   │   └── com
    │   │   │       └── nellyxinwei
    │   │   │           └── backend
    │   │   │               ├── BackendApplication.java
    │   │   │               ├── config
    │   │   │               │   ├── JwtAthFilter.java
    │   │   │               │   ├── JwtUtils.java
    │   │   │               │   └── SecurityConfig.java
    │   │   │               ├── controllers
    │   │   │               │   ├── AuthenticationController.java
    │   │   │               │   └── GreetingsController.java
    │   │   │               └── dto
    │   │   │                   └── AuthenticationRequest.java

[njtalba5127]

create a new bean inside SecurityConfig.java

SecurityConfig.java

package com.nellyxinwei.backend.config;

import java.util.Collection;
import java.util.Collections;
import java.util.List;

import org.apache.tomcat.jni.User;
import org.springframework.context.annotation.Bean;
import org.springframework.security.authentication.AuthenticationManager;
import org.springframework.security.authentication.AuthenticationProvider;
import org.springframework.security.authentication.dao.DaoAuthenticationProvider;
import org.springframework.security.config.annotation.authentication.configuration.AuthenticationConfiguration;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
import org.springframework.security.config.http.SessionCreationPolicy;
import org.springframework.security.core.authority.SimpleGrantedAuthority;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.security.core.userdetails.UserDetailsService;
import org.springframework.security.core.userdetails.UsernameNotFoundException;
import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
import org.springframework.security.crypto.password.NoOpPasswordEncoder;
import org.springframework.security.crypto.password.PasswordEncoder;
import org.springframework.security.web.SecurityFilterChain;
import org.springframework.security.web.authentication.UsernamePasswordAuthenticationFilter;

import io.jsonwebtoken.lang.Arrays;
import lombok.RequiredArgsConstructor;

@EnableWebSecurity
@RequiredArgsConstructor
public class SecurityConfig {

  private final JwtAthFilter jwtAthFilter;

  private final static List<UserDetails>APPLICATION_USERS = Arrays.asList(
    new User(
      "[email protected]",
      "password",
      Collections.singleton(new SimpleGrantedAuthority("ROLE_ADMIN"))
    ),
    new User(
      "[email protected]",
      "password",
      Collections.singleton(new SimpleGrantedAuthority("ROLE_USER"))
    )
  )

  @Bean
  public SecurityFilterChain securityFilterChain(HttpSecurity http) throws Exception {
    http
        .authorizeRequests()
        .anyRequest()
        .authenticated()
        .and()
        .sessionManagement()
        .sessionCreationPolicy(SessionCreationPolicy.STATELESS)
        .and()
        .authenticationProvider(authenticationProvider())
        .addFilterBefore(jwtAthFilter, UsernamePasswordAuthenticationFilter.class);
    return http.build();
  }

  @Bean
  public AuthenticationProvider authenticationProvider() {
    final DaoAuthenticationProvider authenticationProvider = new DaoAuthenticationProvider();
    authenticationProvider.setUserDetailsService(userDetailsService());
    authenticationProvider.setPasswordEncoder(passwordEncoder());
    return authenticationProvider;
  }

  @Bean
  public AuthenticationManager authenticationManager(AuthenticationConfiguration config) throws Exception{
    return config.getAuthenticationManager();
  }

  @Bean
  public PasswordEncoder passwordEncoder() {
    // return new BCryptPasswordEncoder();
    return NoOpPasswordEncoder.getInstance();
  }

  @Bean
  public UserDetailsService userDetailsService() {
    return new UserDetailsService() {
      @Override
      public UserDetails loadUserByUsername(String email) throws UsernameNotFoundException {
        return APPLICATION_USERS
            .stream()
            .filter(u -> u.getUsername().equals(email))
            .findFirst()
            .orElseThrow(() -> new UsernameNotFoundException("No user was found"));
      }
    };
  }
}

[njtalba5127]

back to our AuthenticationController.java

AuthenticationController.java

package com.nellyxinwei.backend.controllers;

import org.springframework.http.ResponseEntity;
import org.springframework.security.authentication.AuthenticationManager;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.security.core.userdetails.UserDetailsService;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import com.nellyxinwei.backend.config.JwtUtils;
import com.nellyxinwei.backend.dto.AuthenticationRequest;

import lombok.RequiredArgsConstructor;

@RestController
@RequestMapping("/api/v1/auth")
@RequiredArgsConstructor
public class AuthenticationController {

  private final AuthenticationManager authenticationManager;
  private final UserDetailsService userDetailsService;
  private final JwtUtils jwtUtils;

  @PostMapping("/authenticate")
  public ResponseEntity<String> authenticate(
      @RequestBody AuthenticationRequest request) {
    authenticationManager.authenticate(
        new UsernamePasswordAuthenticationToken(request.getEmail(), request.getPassword()));
    final UserDetails user = userDetailsService.loadUserByUsername(request.getEmail());
    if (user != null) {
      return ResponseEntity.ok(jwtUtils.generateToken(user));
    }
    return ResponseEntity.status(400).body("Some error has occured");
  }
}