fix: switching to a string for the fields (#50094)

* fix: switching to a string for the fields

closes: #48734

Signed-off-by: Steve Hawkins <shawkins@redhat.com>

* Apply suggestions from code review

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
Signed-off-by: Steven Hawkins <shawkins@redhat.com>

* further suggestions and removing the request filter

Signed-off-by: Steve Hawkins <shawkins@redhat.com>

---------

Signed-off-by: Steve Hawkins <shawkins@redhat.com>
Signed-off-by: Steven Hawkins <shawkins@redhat.com>
Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

integration/admin-client/src/main/java/org/keycloak/admin/client/Keycloak.java

@@ -218,12 +218,12 @@ public class Keycloak implements AutoCloseable {
     }
     
     /**
-     * Create a secure proxy with endpoints targetting the server
+     * Create a secure proxy with endpoints targeting the server
      */
     public <T> T proxy(Class<T> proxyClass) {
         return CLIENT_PROVIDER.targetProxy(target, proxyClass);
     }
-
+    
     /**
      * Closes the underlying client. After calling this method, this <code>Keycloak</code> instance cannot be reused.
      */

js/libs/keycloak-admin-client/openapi.json

@@ -236,15 +236,16 @@
         "tags" : [ "Clients (v2)" ],
         "parameters" : [ {
           "description" : "Set of fields to include in the response. Must be top-level fields. If omitted or empty, all fields will be populated.",
-          "name" : "fields",
-          "in" : "query",
+          "explode" : false,
           "schema" : {
             "type" : "array",
             "uniqueItems" : true,
             "items" : {
               "type" : "string"
             }
-          }
+          },
+          "name" : "fields",
+          "in" : "query"
         }, {
           "description" : "Filter expression using SCIM-like syntax, e.g. clientId eq \"my-app\" and enabled eq true",
           "name" : "q",

rest/admin-v2/api/pom.xml

@@ -45,6 +45,11 @@
             <artifactId>hibernate-validator</artifactId>
             <scope>provided</scope>
         </dependency>
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter</artifactId>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
 
     <build>

rest/admin-v2/api/src/main/java/org/keycloak/admin/api/ListOptions.java

@@ -1,16 +1,23 @@
 package org.keycloak.admin.api;
 
+import java.util.LinkedHashSet;
+import java.util.List;
 import java.util.Set;
+import java.util.stream.Collectors;
 
 import jakarta.ws.rs.QueryParam;
 
+import org.eclipse.microprofile.openapi.annotations.enums.Explode;
+import org.eclipse.microprofile.openapi.annotations.enums.SchemaType;
+import org.eclipse.microprofile.openapi.annotations.media.Schema;
 import org.eclipse.microprofile.openapi.annotations.parameters.Parameter;
 
 public class ListOptions {
 
-    @Parameter(description = "Set of fields to include in the response. Must be top-level fields. If omitted or empty, all fields will be populated.")
+    @Parameter(description = "Set of fields to include in the response. Must be top-level fields. If omitted or empty, all fields will be populated.", 
+            explode = Explode.FALSE, schema = @Schema(type = SchemaType.ARRAY, uniqueItems = true, implementation = String.class))
     @QueryParam("fields")
-    protected Set<String> fields;
+    protected String fields;
 
     @Parameter(description = "Filter expression using SCIM-like syntax, e.g. clientId eq \"my-app\" and enabled eq true")
     @QueryParam("q")
@@ -27,11 +34,17 @@ public class ListOptions {
     }
 
     public Set<String> getFields() {
-        return fields;
+        if (fields == null) {
+            return null;
+        }
+        if (fields.isEmpty()) {
+            return Set.of();
+        }
+        return new LinkedHashSet<>(List.of(fields.split(",")));
     }
 
     public void setFields(Set<String> fields) {
-        this.fields = fields;
+        this.fields = fields == null ? null : fields.stream().collect(Collectors.joining(","));
     }
 
     public String getQuery() {
@@ -41,5 +54,5 @@ public class ListOptions {
     public void setQuery(String query) {
         this.query = query;
     }
-
+    
 }

rest/admin-v2/api/src/test/java/org/keycloak/admin/api/ListOptionsTest.java

@@ -0,0 +1,26 @@
+package org.keycloak.admin.api;
+
+import java.util.Set;
+
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+public class ListOptionsTest {
+
+    @Test
+    void testGetFieldsEmpty() {
+        ListOptions options = new ListOptions();
+        options.setFields(Set.of());
+        assertEquals("", options.fields);
+        assertEquals(Set.of(), options.getFields());
+    }
+    
+    @Test
+    void testGetFields() {
+        ListOptions options = new ListOptions();
+        options.fields = "a,b";
+        assertEquals(Set.of("a", "b"), options.getFields());
+    }
+
+}

rest/admin-v2/tests/src/test/java/org/keycloak/tests/admin/client/v2/ClientApiV2Test.java

@@ -20,6 +20,7 @@ package org.keycloak.tests.admin.client.v2;
 import java.io.ByteArrayInputStream;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
+import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Locale;
 import java.util.Set;
@@ -365,6 +366,10 @@ public class ClientApiV2Test extends AbstractClientApiV2Test{
     public void invalidFieldProjection() {
         BadRequestException e = assertThrows(BadRequestException.class, () -> getClientsApi().getClients(new ListOptions().fields(Set.of("unknown!"))));
         assertEquals("{\"error\":\"unknown! is an unknown field\"}", e.getResponse().readEntity(String.class));
+        
+        // ensure that multiple fields are interpreted correctly
+        e = assertThrows(BadRequestException.class, () -> getClientsApi().getClients(new ListOptions().fields(new LinkedHashSet<>(List.of("clientId","unknown!")))));
+        assertEquals("{\"error\":\"unknown! is an unknown field\"}", e.getResponse().readEntity(String.class));
     }
 
     @Test