Spring Security form login only offers application/json req body type when login page customized

[isaladkou]

Describe the bug
This bug is related to #1931
The solution 9c03b6f depends on DefaultLoginPageGeneratingFilter presence. And so it works only if default form is used. But if the login page customized it doesn't work.
To Reproduce
I'm using SpringBoot 2.7.5 and Spring Security 5.7.4. Other project dependencies:

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-security</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springdoc</groupId>
        <artifactId>springdoc-openapi-ui</artifactId>
        <version>1.7.0</version>
    </dependency>
    <dependency>
        <groupId>org.springdoc</groupId>
        <artifactId>springdoc-openapi-security</artifactId>
        <version>1.7.0</version>
    </dependency>
</dependencies>

Supplying property: springdoc.show-login-endpoint=true

Spring security simple config:

@Configuration
@EnableWebSecurity
public class SecurityConfiguration {

    @Bean
    public SecurityFilterChain filterChain(HttpSecurity http) throws Exception {
        http
                .csrf().disable()
                .authorizeRequests()
                .antMatchers("/v3/api-docs/**",
                        "/swagger-ui/**",
                        "/swagger-ui.html").permitAll()
                .anyRequest().authenticated()
                .and()
                .formLogin()
                .loginPage("/notdefault");
        return http.build();
    }

    @Autowired
    public void configureGlobal(AuthenticationManagerBuilder auth, PasswordEncoder passwordEncoder) throws Exception {
        auth.inMemoryAuthentication()
                .withUser("user")
                .password(passwordEncoder.encode("password"))
                .roles("USER");
    }

}

A simple controller:

@RestController
@RequestMapping("foos")
public class FooController {

    @GetMapping(value = "/{id}")
    public Foo findById(@PathVariable("id") final Long id) {
        return new Foo(randomAlphabetic(6));
    }

    @GetMapping
    public List<Foo> findAll() {
        return Lists.newArrayList(new Foo(randomAlphabetic(6)));
    }

    @PostMapping
    @ResponseStatus(HttpStatus.CREATED)
    public Foo create(@RequestBody final Foo foo) {
        return foo;
    }
}

Expected behavior
I would have expected that form-login authentication configuration would be detected and the exposed Spring Security's detected login endpoint to be exposed with the option for x-www-form-urlencoded body type to be available.

Screenshots

https://drive.google.com/file/d/1LYJ9zkE0m4emA96AmITds1KxT90I6rxj/view?usp=drive_link

Additional context
I have also created this repo with the sample code: https://github.com/isaladkou/springdoc-form-login

[bnasslahsen]

springdoc-openapi v1.7.0 is the latest Open Source release supporting Spring Boot 2.x and 1.x.

An extended support for springdoc-openapi v1
project is now available for organizations that need support beyond 2023.

For more details, feel free to reach out: sales@springdoc.org

[xmichael91]

Hello, @bnasslahsen! This bug also applies to springdoc-openapi v2.3.0.