Loading Properties with same prefix in Spring Security using Spring Boot - spring-boot

Question

I am authenticating an application with a login page using Spring Seurity and Spring Boot. I am storing user credentials in a properties file (until we finalize a Database) with password in encrypted for starting 5 users.
Here is my properties file
User.properties
my.web.user[0].username=John
my.web.user[0].password=$2y$12$V
my.web.user[0].role=ADMIN,USER
my.web.user[1].username=Johny
my.web.user[1].password=$2y$12$5C
my.web.user[1].role=ADMIN,USER
my.web.user[2].username=McCain
my.web.user[2].password=$2y$12$ERL8mf5.
my.web.user[2].role=USER
So now we can add as many users we want but in this array format. Now, I am loading this properties file in Spring Boot.
MyWebApplication.java
#SpringBootApplication
#ComponentScan(basePackages = { "com.myorg.module" })
#EnableConfigurationProperties(UserConfig.class)
public class MyWebApplication {
public static void main(String[] args) {
ApplicationContext appCtxt = SpringApplication.run(MyWebApplication.class, args);
}
}
UserConfig.java
#Configuration
#PropertySource("user.properties")
#ConfigurationProperties(prefix="my.web")
public class UserConfig {
private List<User> user;
/**
* #return the user
*/
public List<User> getUser() {
return user;
}
/**
* #param user the user to set
*/
public void setUser(List<User> user) {
this.user = user;
}
}
UserDetailsServiceImpl
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.security.core.userdetails.User.UserBuilder;
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.stereotype.Component;
import UserConfig;
import User;
#Component
public class UserDetailsServiceImpl implements UserDetailsService{
#Autowired
private UserConfig userConfig;
#Override
public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException {
User user = findUserByUsername(username);
UserBuilder userBuilder = null;
if(user != null) {
userBuilder = org.springframework.security.core.userdetails.User.withUsername(username);
userBuilder.password(new BCryptPasswordEncoder().encode(user.getPassword()));
userBuilder.roles(user.getRoles());
}else {
throw new UsernameNotFoundException("User Not Found");
}
return userBuilder.build();
}
private User findUserByUsername(String username) {
System.out.println(userConfig);
return userConfig.getUser().get(0);
}
}
Now when I am loading the UserConfig into my UserDetailsServiceImpl using #Autowired. In this case, I am getting userConfig as null. However, when I am putting debug points into getter/setter in UserConfig. I can see that it is populating object with properties contents on Container startup. But later on it vanishes and make it NULL.
Can anyone let me know where am I making mistake?
Thanks in advance.

Answer 1

There are couple of learnings which I had on this.
WebSecurityConfigurerAdapter subclass - This child class should have #Autowired the UserDetailsService interface. In my case, I wrote UserDetailsServiceImpl which is the implementation of UserDetailsService interface.
Properties' array key name must match with the variable name of the #Configuration class. In my case, in properties, I had
my.web.user[0].username=John
and the variable name must be the same in #Configuration class like
#Configuration
#ConfigurationProperties(prefix="my.web")
#PropertySource("user.properties")
public class UserConfig {
private List<User> **user**;
And then it suddenly started working.
P.S. - I did lot of googling and research but nothing worked. Then I read this document 3 times to get it worked.