We have a Spring Boot microservice that does the SOAP call to the external system using org.springframework.ws.client.core.WebServiceTemplate.
Now the system would be protected with Keycloak, so all the request need to beak the auth token.
If it was a REST API, I would just replace the pre-existed RestTemplate with OAuth2RestTemplate. But how to instrument the calls initially done by the org.springframework.ws.client.core.WebServiceTemplate ?
So, I understand, I should put the authentication header manually with value 'Bearer ....token there...'. How I can retrieve that part manually to put it into the request?
The problem was caused by
Existing library code, based on org.springframework.ws.client.core.WebServiceTemplate, so large and huge for rewriting it using WebClient, compatible with OAuth2 SpringSecurity or use depricated OAuth2RestTemplate
The webservice we previously communicated with, turns into protected with Gravitee and accepts queries with JWT tokens only. So, the only change here is to add the Authentication header with 'Bearer ....token there...'
We initiate the call from the scheduled jo in the microservice. So, it should be getting token from the Keycloak before the request and be able to update it with time. No one does the explicit authorization like in the frontend, so the OAuth2 client should use client-id and client-secret to connect with no human involved
At the beginning, we define the Interceptor to the SOAP calls, that will pass the token as a header, via a Supplier function taking it wherever it can be taken:
public class JwtClientInterceptor implements ClientInterceptor {
private final Supplier<String> jwtToken;
public JwtClientInterceptor(Supplier<String> jwtToken) {
this.jwtToken = jwtToken;
}
@Override
public boolean handleRequest(MessageContext messageContext) {
SoapMessage soapMessage = (SoapMessage) messageContext. getRequest();
SoapHeader soapHeader = soapMessage.getSoapHeader();
soapHeader.addHeaderElement(new QName("authorization"))
.setText(String. format("Bearer %s", jwtToken.get()));
return true;
}
@Override
public boolean handleResponse(MessageContext messageContext) throws WebServiceClientException {
return true;
}
@Override
public boolean handleFault(MessageContext messageContext) throws WebServiceClientException {
return true;
}
@Override
public void afterCompletion(MessageContext messageContext, Exception ex) throws WebServiceClientException {
}
}
Then pass it to the template in addition to other pre-existed interceptor to be called in config class:
protected WebServiceTemplate buildWebServiceTemplate(Jaxb2Marshaller marshaller,
HttpComponentsMessageSender messageSender, String uri, Supplier<String> jwtToken) {
WebServiceTemplate template = new WebServiceTemplate();
template.setMarshaller(marshaller);
template.setUnmarshaller(marshaller);
template.setMessageSender(messageSender);
template.setDefaultUri(uri);
ClientInterceptor[] clientInterceptors = ArrayUtils.addAll(template.getInterceptors(), new Logger(), new JwtClientInterceptor(jwtToken));
template.setInterceptors(clientInterceptors);
return template;
}
Then add the Spring Security Oath2 Client library
compile 'org.springframework.security:spring-security-oauth2-client:5.2.1.RELEASE'
We create OAuth2AuthorizedClientService bean, that uses a standard ClientRegistrationRepository (the repository is initiated through usage of @EnableWebSecurity annotation on the @Configuration class, but please double check about that)
@Bean
public OAuth2AuthorizedClientService oAuth2AuthorizedClientService(ClientRegistrationRepository clientRegistrationRepository) {
return new InMemoryOAuth2AuthorizedClientService(clientRegistrationRepository);
}
Then create a OAuth2AuthorizedClientManager
@Bean
public OAuth2AuthorizedClientManager authorizedClientManager(
ClientRegistrationRepository clientRegistrationRepository,
OAuth2AuthorizedClientRepository authorizedClientRepository) {
Authentication authentication = new Authentication() {
@Override
public Collection<? extends GrantedAuthority> getAuthorities() {
GrantedAuthority grantedAuthority = new GrantedAuthority() {
@Override
public String getAuthority() {
return "take_a_needed_value_from_property";
}
};
return Arrays.asList(grantedAuthority);
}
@Override
public Object getCredentials() {
return null;
}
@Override
public Object getDetails() {
return null;
}
@Override
public Object getPrincipal() {
return new Principal() {
@Override
public String getName() {
return "our_client_id_from_properties";
}
};
}
@Override
public boolean isAuthenticated() {
return true;
}
@Override
public void setAuthenticated(boolean isAuthenticated) throws IllegalArgumentException {
}
@Override
public String getName() {
return "take_a_needed_name_from_properties";
}
};
//we need to emulate Principal there, as other classes relies on it. In fact, Principal isn't needed for the app which is a client and just do the call, as nothing is authorized in the app against this Principal itself
OAuth2AuthorizationContext oAuth2AuthorizationContext = OAuth2AuthorizationContext.withClientRegistration(clientRegistrationRepository.findByRegistrationId("keycloak")).
principal(authentication).
build();
oAuth2AuthorizationContext.getPrincipal().setAuthenticated(true);
oAuth2AuthorizationContext.getAuthorizedClient();
OAuth2AuthorizedClientProvider authorizedClientProvider = OAuth2AuthorizedClientProviderBuilder.builder().
//refreshToken().
clientCredentials(). //- we use this one according to our set up
//authorizationCode().
build();
OAuth2AuthorizedClientService oAuth2AuthorizedClientService = oAuth2AuthorizedClientService(clientRegistrationRepository); //use the bean from before step here
AuthorizedClientServiceOAuth2AuthorizedClientManager authorizedClientManager =
new AuthorizedClientServiceOAuth2AuthorizedClientManager(
clientRegistrationRepository, oAuth2AuthorizedClientService);
OAuth2AuthorizedClient oAuth2AuthorizedClient = authorizedClientProvider.authorize(oAuth2AuthorizationContext);
authorizedClientManager.setAuthorizedClientProvider(authorizedClientProvider);
oAuth2AuthorizedClientService.saveAuthorizedClient(oAuth2AuthorizedClient,
oAuth2AuthorizationContext.getPrincipal());
//this step is needed, as without explicit authorize call, the
//oAuth2AuthorizedClient isn't initialized in the service
return authorizedClientManager;
}
Provide a method for supplied function that can be called each time to retrieve the JWT token from the security stuff (repository and manager). Here it should be auto-updated, so we just call for retrieving it
public Supplier<String> getJwtToken() {
return () -> {
OAuth2AuthorizedClient authorizedClient = authorizedClientService.loadAuthorizedClient("keycloak", "we_havePout_realm_there_from_the_properties");
return authorizedClient.getAccessToken().getTokenValue();
};
}
Pass this Consumer to the @Bean, defining the WebServiceTemplate's
@Bean
public Client client(@Qualifier("Sender1") HttpComponentsMessageSender bnfoMessageSender,
@Qualifier("Sender2") HttpComponentsMessageSender uhMessageSender) {
WebServiceTemplate sender1= buildWebServiceTemplate(buildSender1Marshaller(), sender1MessageSender, properties.getUriSender1(),getJwtToken());
WebServiceTemplate sender2 = buildWebServiceTemplate(buildSender2Marshaller(), sender2MessageSender, properties.getUriSender2(),getJwtToken());
return buildClient(buildRetryTemplate(), sender1, sender2);
}
We add Spring Security Client values to application.yaml in order to configure it.
spring:
security:
oauth2:
client:
provider:
keycloak:
issuer-uri: https://host/keycloak/auth/realms/ourrealm
registration:
keycloak:
client-id: client_id
client-secret: client-secret-here
authorization-grant-type: client_credentials //need to add explicitly, otherwise would try other grant-type by default and never get the token!
client-authentication-method: post //need to have this explicitly, otherwise use basic that doesn't fit best the keycloak set up
scope: openid //if your don't have it, it checks all available scopes on url like https://host/keycloak/auth/realms/ourrealm/ .well-known/openid-configuration keycloak and then sends them as value of parameter named 'scope' in the query for retrieving the token; that works wrong on our keycloak, so to replace this auto-picked value, we place the explicit scopes list here