SONAR-20607 New isDefault flag on api/qualitygates/show endpoint

server/sonar-webserver-webapi/src/it/java/org/sonar/server/qualitygate/ws/ShowActionIT.java

 import static org.assertj.core.api.Assertions.assertThatThrownBy;
 import static org.assertj.core.api.AssertionsForClassTypes.tuple;
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.mock;
 
   }
 
+  @Test
+  public void reponse_should_show_isDefault() {
+    QualityGateDto defaultQualityGate = db.qualityGates().insertQualityGate();
+    db.qualityGates().setDefaultQualityGate(defaultQualityGate);
+
+    ShowWsResponse response = ws.newRequest()
+      .setParam("name", defaultQualityGate.getName())
+      .executeProtobuf(ShowWsResponse.class);
+
+    assertTrue(response.getIsDefault());
+
+    QualityGateDto nonDefaultQualityGate = db.qualityGates().insertQualityGate();
+
+    response = ws.newRequest()
+      .setParam("name", nonDefaultQualityGate.getName())
+      .executeProtobuf(ShowWsResponse.class);
+
+    assertFalse(response.getIsDefault());
+  }
+
   @Test
   public void fail_when_no_name() {
     QualityGateDto qualityGate = db.qualityGates().insertQualityGate();

server/sonar-webserver-webapi/src/main/java/org/sonar/server/qualitygate/ws/ShowAction.java

       .setSince("4.3")
       .setResponseExample(Resources.getResource(this.getClass(), "show-example.json"))
       .setChangelog(
+        new Change("10.3", "'isDefault' field is added to the response"),
         new Change("10.0", "Field 'id' in the response has been removed"),
         new Change("10.0", "Parameter 'id' is removed. Use 'name' instead."),
         new Change("9.9", "'caycStatus' field is added to the response"),
     return ShowWsResponse.newBuilder()
       .setName(qualityGate.getName())
       .setIsBuiltIn(qualityGate.isBuiltIn())
+      .setIsDefault(qualityGate.getUuid().equals(defaultQualityGate.getUuid()))
       .setCaycStatus(caycStatus.toString())
       .addAllConditions(conditions.stream()
         .map(toWsCondition(metricsByUuid))

server/sonar-webserver-webapi/src/main/resources/org/sonar/server/qualitygate/ws/show-example.json

     }
   ],
   "isBuiltIn": false,
+  "isDefault": false,
   "actions": {
     "rename": true,
     "setAsDefault": true,

sonar-ws/src/main/protobuf/ws-qualitygates.proto

 // GET api/qualitygates/show
 message ShowWsResponse {
   optional string id = 1;
-  optional string name = 2;
+  required string name = 2;
   repeated Condition conditions = 3;
-  optional bool isBuiltIn = 4;
+  required bool isBuiltIn = 4;
   optional Actions actions = 5;
-  optional string caycStatus = 6;
+  required string caycStatus = 6;
+  required bool isDefault = 7;
 
   message Condition {
     required string id = 1;