Spring Security custom HTML login page not recognised using thymeleaf - spring

Question

i have followed this link for all configurations to set link up my custom html page for login. However, when i access localhost/login, i am faced with error status 500.
I am unable to render a simple html page when I access localhost:8080/login.
Are there extra configurations needed?
Should the html page be located at templates folder? How does the application know it should render "login.html" ?
Is my controller being recognised?
config
import org.springframework.context.annotation.Configuration;
import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.builders.WebSecurity;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
#EnableWebSecurity
#Configuration
public class SecurityConfiguration extends WebSecurityConfigurerAdapter {
#Override
protected void configure(HttpSecurity http) throws Exception {
http
.authorizeRequests()
.anyRequest().fullyAuthenticated()
.and()
.formLogin()
.loginPage("/login")
.permitAll();
}
}
controller
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
#Controller
public class LoginController {
#GetMapping("/login")
public String login() {
return "login";
}
}
replacing "login" above with below also shows error.
<h1> Login page <h1>
dependencies in pom.xml
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-security</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.ldap</groupId>
<artifactId>spring-ldap-core</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.security</groupId>
<artifactId>spring-security-ldap</artifactId>
</dependency>
<dependency>
<groupId>com.unboundid</groupId>
<artifactId>unboundid-ldapsdk</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
<dependency>
<groupId>com.h2database</groupId>
<artifactId>h2</artifactId>
<scope>runtime</scope>
<version>1.4.193</version>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>org.junit.vintage</groupId>
<artifactId>junit-vintage-engine</artifactId>
</exclusion>
</exclusions>
</dependency>
</dependencies>
login.html is located in templates.
error message:
javax.servlet.ServletException: Circular view path [login]: would dispatch back to the current handler URL [/login] again. Check your ViewResolver setup! (Hint: This may be the result of an unspecified view, due to default view name generation.)
My folder hierachy:

Answer 1

#RestController is a composed annotation that is itself meta-annotated with #Controller and #ResponseBody indicating a controller whose every method inherits the type-level #ResponseBody annotation and therefore writes directly to the response body vs view resolution and rendering with an HTML template.
That's why I advised replacing #Controller by #RestController.
You will not get static resources in your html file. to get this you have to add this.
#Override
public void configure(WebSecurity web) throws Exception {
web
.ignoring()
.antMatchers("/resources/**", "/static/**", "/css/**", "/js/**", "/images/**");
}

Answer 2

Its behaving as if it cant find your controller. Did you put it in the same package as the main class or deeper in the hierachy?
The component scan which looks for the controller annotation scans from the package your main class is in and beneath it. If you put the controller further out in your folder hierachy it isnt found.

Answer 3

Ok, I have managed to resolved the error but was not conclusive of the cause of it.
The ultimate fix was to keep the mapping url to "/login" in the LoginController and SecurityConfiguration files, and to changed the naming of my html and thymeleaf's references of it in my controller file and html file name as per below.
#Controller
public class LoginController {
#GetMapping("/login")
public String login2() {
return "login2";
}
}
The main reason I would believe has been causing this is because my application and package name were also named "login" which made thymeleaf unable to refer to the right file properly. I have selected the answer above as best answer for others who faced the issue due to different reasons to try out the same experiment to obtain their useful result.