From e435e12f1fd00a5f78621ec1933a60171fc224e6 Mon Sep 17 00:00:00 2001
From: Xiaoyu Yao <xyao@apache.org>
Date: Tue, 18 Sep 2018 23:21:29 -0700
Subject: [PATCH] HDDS-506. Fields in AllocateScmBlockResponseProto should be
 optional. Contributed by Arpit Agarwal.

---
 .../common/src/main/proto/ScmBlockLocationProtocol.proto    | 6 +++---
 .../org/apache/hadoop/hdds/scm/exceptions/SCMException.java | 3 ++-
 .../apache/hadoop/hdds/scm/pipelines/PipelineSelector.java  | 4 ++++
 3 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/hadoop-hdds/common/src/main/proto/ScmBlockLocationProtocol.proto b/hadoop-hdds/common/src/main/proto/ScmBlockLocationProtocol.proto
index 53f408ae88..9b4e0acaba 100644
--- a/hadoop-hdds/common/src/main/proto/ScmBlockLocationProtocol.proto
+++ b/hadoop-hdds/common/src/main/proto/ScmBlockLocationProtocol.proto
@@ -104,9 +104,9 @@ message AllocateScmBlockResponseProto {
     unknownFailure = 4;
   }
   required Error errorCode = 1;
-  required BlockID blockID = 2;
-  required hadoop.hdds.Pipeline pipeline = 3;
-  required bool createContainer = 4;
+  optional BlockID blockID = 2;
+  optional hadoop.hdds.Pipeline pipeline = 3;
+  optional bool createContainer = 4;
   optional string errorMessage = 5;
 }
 
diff --git a/hadoop-hdds/server-scm/src/main/java/org/apache/hadoop/hdds/scm/exceptions/SCMException.java b/hadoop-hdds/server-scm/src/main/java/org/apache/hadoop/hdds/scm/exceptions/SCMException.java
index 87a29e3a5d..dae0b06505 100644
--- a/hadoop-hdds/server-scm/src/main/java/org/apache/hadoop/hdds/scm/exceptions/SCMException.java
+++ b/hadoop-hdds/server-scm/src/main/java/org/apache/hadoop/hdds/scm/exceptions/SCMException.java
@@ -118,6 +118,7 @@ public enum ResultCodes {
     SCM_NOT_INITIALIZED,
     DUPLICATE_DATANODE,
     NO_SUCH_DATANODE,
-    NO_REPLICA_FOUND
+    NO_REPLICA_FOUND,
+    FAILED_TO_FIND_ACTIVE_PIPELINE
   }
 }
diff --git a/hadoop-hdds/server-scm/src/main/java/org/apache/hadoop/hdds/scm/pipelines/PipelineSelector.java b/hadoop-hdds/server-scm/src/main/java/org/apache/hadoop/hdds/scm/pipelines/PipelineSelector.java
index c9f51f7a42..82946bdd7d 100644
--- a/hadoop-hdds/server-scm/src/main/java/org/apache/hadoop/hdds/scm/pipelines/PipelineSelector.java
+++ b/hadoop-hdds/server-scm/src/main/java/org/apache/hadoop/hdds/scm/pipelines/PipelineSelector.java
@@ -62,6 +62,7 @@
 
 import static org.apache.hadoop.hdds.scm.exceptions.SCMException.ResultCodes
     .FAILED_TO_CHANGE_PIPELINE_STATE;
+import static org.apache.hadoop.hdds.scm.exceptions.SCMException.ResultCodes.FAILED_TO_FIND_ACTIVE_PIPELINE;
 import static org.apache.hadoop.hdds.server
         .ServerUtils.getOzoneMetaDirPath;
 import static org.apache.hadoop.ozone
@@ -285,6 +286,9 @@ public Pipeline getReplicationPipeline(ReplicationType replicationType,
       // try to return a pipeline from already allocated pipelines
       PipelineID pipelineId =
               manager.getPipeline(replicationFactor, replicationType);
+      if (pipelineId == null) {
+        throw new SCMException(FAILED_TO_FIND_ACTIVE_PIPELINE);
+      }
       pipeline = pipelineMap.get(pipelineId);
       Preconditions.checkArgument(pipeline.getLifeCycleState() ==
               LifeCycleState.OPEN);