feat: configured authentification

MyINPulse-back/src/main/java/enseirb/myinpulse/security/KeycloakJwtRolesConverter.java

@@ -0,0 +1,98 @@
+package enseirb.myinpulse.security;
+
+import org.springframework.core.convert.converter.Converter;
+import org.springframework.security.authentication.AbstractAuthenticationToken;
+import org.springframework.security.core.GrantedAuthority;
+import org.springframework.security.core.authority.SimpleGrantedAuthority;
+import org.springframework.security.oauth2.jwt.Jwt;
+import org.springframework.security.oauth2.server.resource.authentication.JwtAuthenticationToken;
+import org.springframework.security.oauth2.server.resource.authentication.JwtGrantedAuthoritiesConverter;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Map;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+import static java.util.stream.Collectors.toSet;
+
+
+public class KeycloakJwtRolesConverter implements Converter<Jwt, AbstractAuthenticationToken> {
+    /**
+     * Prefix used for realm level roles.
+     */
+    public static final String PREFIX_REALM_ROLE = "ROLE_REALM_";
+    /**
+     * Prefix used in combination with the resource (client) name for resource level roles.
+     */
+    public static final String PREFIX_RESOURCE_ROLE = "ROLE_";
+
+    /**
+     * Name of the claim containing the realm level roles
+     */
+    private static final String CLAIM_REALM_ACCESS = "realm_access";
+    /**
+     * Name of the claim containing the resources (clients) the user has access to.
+     */
+    private static final String CLAIM_RESOURCE_ACCESS = "resource_access";
+    /**
+     * Name of the claim containing roles. (Applicable to realm and resource level.)
+     */
+    private static final String CLAIM_ROLES = "roles";
+
+    @Override
+    public AbstractAuthenticationToken convert(Jwt source)
+    {
+        return new JwtAuthenticationToken(source, Stream.concat(new JwtGrantedAuthoritiesConverter().convert(source)
+                        .stream(), TEMPORARNAME(source).stream())
+                .collect(toSet()));
+    }
+
+    /**
+     * Extracts the realm and resource level roles from a JWT token distinguishing between them using prefixes.
+     */
+    public Collection<GrantedAuthority> TEMPORARNAME(Jwt jwt) {
+        // Collection that will hold the extracted roles
+        Collection<GrantedAuthority> grantedAuthorities = new ArrayList<>();
+
+        // Realm roles
+        // Get the part of the access token that holds the roles assigned on realm level
+        Map<String, Collection<String>> realmAccess = jwt.getClaim(CLAIM_REALM_ACCESS);
+
+        // Verify that the claim exists and is not empty
+        if (realmAccess != null && !realmAccess.isEmpty()) {
+            // From the realm_access claim get the roles
+            Collection<String> roles = realmAccess.get(CLAIM_ROLES);
+            // Check if any roles are present
+            if (roles != null && !roles.isEmpty()) {
+                // Iterate of the roles and add them to the granted authorities
+                Collection<GrantedAuthority> realmRoles = roles.stream()
+                        // Prefix all realm roles with "ROLE_realm_"
+                        .map(role -> new SimpleGrantedAuthority(PREFIX_REALM_ROLE + role))
+                        .collect(Collectors.toList());
+                grantedAuthorities.addAll(realmRoles);
+            }
+        }
+
+        // Resource (client) roles
+        // A user might have access to multiple resources all containing their own roles. Therefore, it is a map of
+        // resource each possibly containing a "roles" property.
+        Map<String, Map<String, Collection<String>>> resourceAccess = jwt.getClaim(CLAIM_RESOURCE_ACCESS);
+
+        // Check if resources are assigned
+        if (resourceAccess != null && !resourceAccess.isEmpty()) {
+            // Iterate of all the resources
+            resourceAccess.forEach((resource, resourceClaims) -> {
+                // Iterate of the "roles" claim inside the resource claims
+                resourceClaims.get(CLAIM_ROLES).forEach(
+                        // Add the role to the granted authority prefixed with ROLE_ and the name of the resource
+                        role -> grantedAuthorities.add(new SimpleGrantedAuthority(PREFIX_RESOURCE_ROLE + resource + "_" + role))
+                );
+            });
+        }
+
+        return grantedAuthorities;
+    }
+
+
+}