Update getFlushState api (#650)

Signed-off-by: groot <yihua.mo@zilliz.com>

src/main/java/io/milvus/client/AbstractMilvusGrpcClient.java

@@ -1903,6 +1903,8 @@ public abstract class AbstractMilvusGrpcClient implements MilvusClient {
         try {
             GetFlushStateRequest getFlushStateRequest = GetFlushStateRequest.newBuilder()
                     .addAllSegmentIDs(requestParam.getSegmentIDs())
+                    .setCollectionName(requestParam.getCollectionName())
+                    .setFlushTs(requestParam.getFlushTs())
                     .build();
 
             GetFlushStateResponse response = blockingStub().getFlushState(getFlushStateRequest);

src/main/java/io/milvus/client/MilvusClient.java

@@ -426,7 +426,7 @@ public interface MilvusClient {
     R<GetMetricsResponse> getMetrics(GetMetricsParam requestParam);
 
     /**
-     * Get flush state of specified segments.
+     * Get flush state of specified collection.
      *
      * @param requestParam {@link GetFlushStateParam}
      * @return {status:result code, data:GetMetricsResponse{status,metrics}}

src/main/java/io/milvus/param/control/GetFlushStateParam.java

@@ -1,6 +1,7 @@
 package io.milvus.param.control;
 
 import io.milvus.exception.ParamException;
+import io.milvus.param.ParamUtils;
 import lombok.Getter;
 import lombok.NonNull;
 
@@ -13,9 +14,13 @@ import java.util.List;
 @Getter
 public class GetFlushStateParam {
     private final List<Long> segmentIDs;
+    private final String collectionName;
+    private final Long flushTs;
 
     private GetFlushStateParam(@NonNull Builder builder) {
         this.segmentIDs = builder.segmentIDs;
+        this.collectionName = builder.collectionName;
+        this.flushTs = builder.flushTs;
     }
 
     public static Builder newBuilder() {
@@ -26,7 +31,9 @@ public class GetFlushStateParam {
      * Builder for {@link GetFlushStateParam} class.
      */
     public static final class Builder {
-        private final List<Long> segmentIDs = new ArrayList<>();
+        private final List<Long> segmentIDs = new ArrayList<>(); // deprecated
+        private String collectionName;
+        private Long flushTs = 0L;
 
         private Builder() {
         }
@@ -37,6 +44,7 @@ public class GetFlushStateParam {
          * @param segmentIDs segments id list
          * @return <code>Builder</code>
          */
+        @Deprecated
         public Builder withSegmentIDs(@NonNull List<Long> segmentIDs) {
             this.segmentIDs.addAll(segmentIDs);
             return this;
@@ -48,20 +56,41 @@ public class GetFlushStateParam {
          * @param segmentID segment id
          * @return <code>Builder</code>
          */
+        @Deprecated
         public Builder addSegmentID(@NonNull Long segmentID) {
             this.segmentIDs.add(segmentID);
             return this;
         }
 
+        /**
+         * Sets the collection name. Collection name cannot be empty or null.
+         *
+         * @param collectionName collection name
+         * @return <code>Builder</code>
+         */
+        public Builder withCollectionName(@NonNull String collectionName) {
+            this.collectionName = collectionName;
+            return this;
+        }
+
+        /**
+         * Input a time stamp of a flush action, get its flush state
+         *
+         * @param flushTs a time stamp returned by the flush() response
+         * @return <code>Builder</code>
+         */
+        public Builder withFlushTs(@NonNull Long flushTs) {
+            this.flushTs = flushTs;
+            return this;
+        }
+
         /**
          * Verifies parameters and creates a new {@link GetFlushStateParam} instance.
          *
          * @return {@link GetFlushStateParam}
          */
         public GetFlushStateParam build() throws ParamException {
-            if (segmentIDs.isEmpty()) {
-                throw new ParamException("Segment id array cannot be empty");
-            }
+            ParamUtils.CheckNullEmptyString(collectionName, "Collection name");
 
             return new GetFlushStateParam(this);
         }
@@ -75,7 +104,8 @@ public class GetFlushStateParam {
     @Override
     public String toString() {
         return "GetFlushStateParam{" +
-                "segmentIDs=" + segmentIDs.toString() +
+                "collectionName='" + collectionName + '\'' +
+                ", flushTs=" + flushTs +
                 '}';
     }
 }

src/test/java/io/milvus/client/MilvusServiceClientTest.java

@@ -2298,8 +2298,8 @@ class MilvusServiceClientTest {
     void getFlushState() {
         List<Long> ids = Arrays.asList(1L, 2L);
         GetFlushStateParam param = GetFlushStateParam.newBuilder()
-                .addSegmentID(1L)
-                .withSegmentIDs(ids)
+                .withCollectionName("dummy")
+                .withFlushTs(100L)
                 .build();
 
         testFuncByName("getFlushState", param);