Add model sequence status in describe model API response

frontend/server/src/main/java/org/pytorch/serve/http/messages/DescribeModelResponse.java

@@ -42,6 +42,7 @@ public class DescribeModelResponse {
     private List<Worker> workers;
     private Metrics metrics;
     private JobQueueStatus jobQueueStatus;
+    private SequenceStatus sequenceStatus;
     private JsonObject customizedMetadata;
 
     public DescribeModelResponse() {
@@ -299,6 +300,14 @@ public void setJobQueueStatus(JobQueueStatus jobQueueStatus) {
         this.jobQueueStatus = jobQueueStatus;
     }
 
+    public SequenceStatus getSequenceStatus() {
+        return sequenceStatus;
+    }
+
+    public void setSequenceStatus(SequenceStatus sequenceStatus) {
+        this.sequenceStatus = sequenceStatus;
+    }
+
     public void setCustomizedMetadata(byte[] customizedMetadata) {
         String stringMetadata = new String(customizedMetadata, Charset.forName("UTF-8"));
         try {
@@ -434,4 +443,16 @@ public void setPendingRequests(int pendingRequests) {
             this.pendingRequests = pendingRequests;
         }
     }
+
+    public static final class SequenceStatus {
+        private int sequenceCount;
+
+        public int getSequenceCount() {
+            return sequenceCount;
+        }
+
+        public void setSequenceCount(int sequenceCount) {
+            this.sequenceCount = sequenceCount;
+        }
+    }
 }

frontend/server/src/main/java/org/pytorch/serve/util/ApiUtils.java

@@ -437,6 +437,11 @@ private static DescribeModelResponse createModelResponse(
         jobQueueStatus.setPendingRequests(model.getPendingRequestsInJobQueue());
         resp.setJobQueueStatus(jobQueueStatus);
 
+        DescribeModelResponse.SequenceStatus sequenceStatus =
+                new DescribeModelResponse.SequenceStatus();
+        sequenceStatus.setSequenceCount(model.getJobGroupCount());
+        resp.setSequenceStatus(sequenceStatus);
+
         return resp;
     }
 

frontend/server/src/main/java/org/pytorch/serve/wlm/Model.java

@@ -638,6 +638,14 @@ public LinkedBlockingDeque<String> getPendingJobGroups() {
         return pendingJobGroups;
     }
 
+    public int getJobGroupCount() {
+        if (jobGroups != null) {
+            return jobGroups.size();
+        }
+
+        return 0;
+    }
+
     public JobGroup getJobGroup(String groupId) {
         return jobGroups.get(groupId);
     }