[improve][rest] Add lookup REST Api swagger docs describe (apache#16470)

pulsar-broker/src/main/java/org/apache/pulsar/broker/lookup/v2/TopicLookup.java

@@ -18,6 +18,8 @@
  */
 package org.apache.pulsar.broker.lookup.v2;
 
+import io.swagger.annotations.Api;
+import io.swagger.annotations.ApiOperation;
 import io.swagger.annotations.ApiResponse;
 import io.swagger.annotations.ApiResponses;
 import javax.ws.rs.DefaultValue;
@@ -34,9 +36,11 @@
 import lombok.extern.slf4j.Slf4j;
 import org.apache.commons.lang3.StringUtils;
 import org.apache.pulsar.broker.lookup.TopicLookupBase;
+import org.apache.pulsar.common.lookup.data.LookupData;
 import org.apache.pulsar.common.naming.TopicName;
 
 @Path("/v2/topic")
+@Api(value = "lookup", tags = "lookup")
 @Slf4j
 public class TopicLookup extends TopicLookupBase {
 
@@ -45,6 +49,10 @@ public class TopicLookup extends TopicLookupBase {
     @GET
     @Path("{topic-domain}/{tenant}/{namespace}/{topic}")
     @Produces(MediaType.APPLICATION_JSON)
+    @ApiOperation(
+            value = "Get the owner broker of the given topic.",
+            response = LookupData.class
+    )
     @ApiResponses(value = { @ApiResponse(code = 307,
             message = "Current broker doesn't serve the namespace of this topic") })
     public void lookupTopicAsync(
@@ -72,6 +80,10 @@ public void lookupTopicAsync(
     @GET
     @Path("{topic-domain}/{tenant}/{namespace}/{topic}/bundle")
     @Produces(MediaType.APPLICATION_JSON)
+    @ApiOperation(
+            value = "Get the namespace bundle which the given topic belongs to.",
+            response = String.class
+    )
     @ApiResponses(value = { @ApiResponse(code = 403, message = "Don't have admin permission"),
             @ApiResponse(code = 405, message = "Invalid topic domain type") })
     public String getNamespaceBundle(@PathParam("topic-domain") String topicDomain,