How can I unit test AuthControllerIntegrationTest and mock JwtDecoder in Spock correctly? - spring-boot

Question

I have a spring security Book store api which is working as expected.
My Security Config class look like this.
#Configuration
public class SecurityConfiguration {
#Bean
JwtDecoder jwtDecoder () {
return JwtDecoders.fromIssuerLocation("https://jwt-issuer-location")
}
#Bean
public SecurityFilterChain filterChain(HttpSecurity http) throws Exception {
http
.authorizeHttpRequests((authz) -> authz
.antMatchers(HttpMethod.GET, '/api/auth/**')
.antMatchers(HttpMethod.GET, '/api/books').authenticated()
.antMatchers(HttpMethod.GET, '/api/users').authenticated()
.anyRequest().authenticated()
.and().httpBasic()
)
.oauth2ResourceServer().jwt()
return http.build();
}
#Bean
InMemoryUserDetailsManagerService() {
UserDetails user = User.builder().username("bob").password("password123").roles("api").build()
return new InMemoryUserDetailsManager(user)
}
}
For controller integrations like returning the list of users and books, I have used #MockBean for JwtDecoder like following
#MockBean
JwtDecoder jwtDecoder
then the test works.
However, for my integration test for authentication, it does not work in the same way. The integration looks like this
#SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
#AutocConfigureMockMvc
class AuthController extends Specification {
MockMvc mockMvc
#Autowired
WebApplicationContext context
def setup() {
this.mockMvc = MockMvcBuilders.webAppContextSetup(this.context).apply(springSecurity()).build()
}
def "401 Unauthorized Exception"() {
given:
String url = "/api/books"
when:
ResultActions res = this.mockMvc.perform(get(url))
then:
response.andExpect(status().is4xxClientError())
}
}
For some reason, this auth controller integration test tries to make a http request for verifying the token sent by the user. the url is passed to jwtDecoders.fromIssuerLocation function.
I believe that is not an ideal way of make a unit test. It is not supposed to make any request to 3rd party
And since this is just the unit test, I passed some random url (I do not want to pass actual url for security purpose and push it. For the production app, I am pulling the actual url from environment variable).
Because of that, when mockMvc.perform runs, it throws I/O error on GET request for .....
I do not understand why other integration works by MockBean annotation on JwtDecoder. But it does not resolve AuthControllerIntegrationTest error.
Can someone tell I how I should mock the JwtDecoder instead?
Thank you in advance :)
I have tried adding MockBean on JwtDecoder but it does not work for AuthControllerIntegrationTest.
I would like to know how to mock the JwtDecoder correctly or maybe how to mock the JwtDecoders.fromIssuerLocation. But I do not know how to mock and return what.