Add "restarted": true or false to POST supervisor update API

Including this in the response will help indicate if the superivsor was restarted or not
if skipRestartIfUnmodified is set to true

Author: abhishekrb19

docs/api-reference/supervisor-api.md

@@ -2508,11 +2508,16 @@ curl "http://ROUTER_IP:ROUTER_PORT/druid/indexer/v1/supervisor?skipRestartIfUnmo
 
   ```json
 {
-    "id": "social_media"
+    "id": "social_media",
+    "restarted": true
 }
   ```
 </details>
 
+The response includes the following fields:
+- `id`: The supervisor ID.
+- `restarted`: A boolean indicating whether the supervisor was restarted. When `skipRestartIfUnmodified` is set to `true` and the supervisor spec is unchanged, this field will be `false`; otherwise, it will be `true`.
+
 ### Suspend a running supervisor
 
 Suspends a single running supervisor. Returns the updated supervisor spec, where the `suspended` property is set to `true`. The suspended supervisor continues to emit logs and metrics.

indexing-service/src/main/java/org/apache/druid/indexing/overlord/supervisor/SupervisorResource.java

@@ -166,7 +166,7 @@ public Response specPost(
           }
 
           if (Boolean.TRUE.equals(skipRestartIfUnmodified) && !manager.shouldUpdateSupervisor(spec)) {
-            return Response.ok(ImmutableMap.of("id", spec.getId())).build();
+            return Response.ok(ImmutableMap.of("id", spec.getId(), "restarted", false)).build();
           }
 
           manager.createOrUpdateAndStartSupervisor(spec);
@@ -183,7 +183,7 @@ public Response specPost(
                         .build()
           );
 
-          return Response.ok(ImmutableMap.of("id", spec.getId())).build();
+          return Response.ok(ImmutableMap.of("id", spec.getId(), "restarted", true)).build();
         }
     );
   }

indexing-service/src/test/java/org/apache/druid/indexing/overlord/supervisor/SupervisorResourceTest.java

@@ -178,7 +178,7 @@ public List<String> getDataSources()
     verifyAll();
 
     Assert.assertEquals(200, response.getStatus());
-    Assert.assertEquals(ImmutableMap.of("id", "my-id"), response.getEntity());
+    Assert.assertEquals(ImmutableMap.of("id", "my-id", "restarted", true), response.getEntity());
     resetAll();
 
     EasyMock.expect(taskMaster.getSupervisorManager()).andReturn(Optional.absent());
@@ -248,7 +248,7 @@ public List<String> getDataSources()
     verifyAll();
 
     Assert.assertEquals(200, response.getStatus());
-    Assert.assertEquals(ImmutableMap.of("id", "my-id"), response.getEntity());
+    Assert.assertEquals(ImmutableMap.of("id", "my-id", "restarted", false), response.getEntity());
 
     resetAll();
 
@@ -269,7 +269,7 @@ public List<String> getDataSources()
     verifyAll();
 
     Assert.assertEquals(200, response.getStatus());
-    Assert.assertEquals(ImmutableMap.of("id", "my-id"), response.getEntity());
+    Assert.assertEquals(ImmutableMap.of("id", "my-id", "restarted", true), response.getEntity());
   }
 
   @Test
@@ -300,7 +300,7 @@ public List<String> getDataSources()
     verifyAll();
 
     Assert.assertEquals(200, response.getStatus());
-    Assert.assertEquals(ImmutableMap.of("id", "my-id"), response.getEntity());
+    Assert.assertEquals(ImmutableMap.of("id", "my-id", "restarted", true), response.getEntity());
     resetAll();
 
     EasyMock.expect(taskMaster.getSupervisorManager()).andReturn(Optional.absent());

processing/src/main/java/org/apache/druid/java/util/emitter/service/ServiceMetricEvent.java

@@ -93,6 +93,11 @@ public String getHost()
     return serviceDims.get(HOST);
   }
 
+  public ImmutableMap<String, String> getServiceDims()
+  {
+    return serviceDims;
+  }
+
   public Map<String, Object> getUserDims()
   {
     return userDims;

server/src/test/java/org/apache/druid/rpc/indexing/OverlordClientImplTest.java

@@ -283,11 +283,11 @@ public void test_postSupervisor() throws Exception
             .jsonContent(jsonMapper, supervisorSpec),
         HttpResponseStatus.OK,
         ImmutableMap.of(HttpHeaders.CONTENT_TYPE, MediaType.APPLICATION_JSON),
-        jsonMapper.writeValueAsBytes(Map.of("id", supervisorId))
+        jsonMapper.writeValueAsBytes(Map.of("id", supervisorId, "restarted", true))
     );
 
     Assert.assertEquals(
-        Map.of("id", supervisorId),
+        Map.of("id", supervisorId, "restarted", true),
         overlordClient.postSupervisor(supervisorSpec).get()
     );
   }