feast-dev · khorshuheng · May 16, 2022 · May 15, 2022
diff --git a/spark/ingestion/src/main/scala/feast/ingestion/errorhanders/RetryStrategy.scala b/spark/ingestion/src/main/scala/feast/ingestion/errorhanders/RetryStrategy.scala
@@ -0,0 +1,37 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ * Copyright 2018-2022 The Feast Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package feast.ingestion.errorhanders
+
+import scala.annotation.tailrec
+import scala.concurrent.duration.Duration
+
+object RetryStrategy {
+
+  @tailrec
+  def fixedBackOff[T <: Exception, U](retryInterval: Duration, maxRetries: Int)(
+      fn: => Either[T, U]
+  ): U = {
+    fn match {
+      case Right(x) => x
+      case Left(_) if maxRetries > 0 => {
+        Thread.sleep(retryInterval.toMillis)
+        fixedBackOff(retryInterval, maxRetries - 1)(fn)
+      }
+      case Left(e) => throw (e)
+    }
+  }
+}
diff --git a/spark/ingestion/src/main/scala/feast/ingestion/stores/redis/ClusterPipelineProvider.scala b/spark/ingestion/src/main/scala/feast/ingestion/stores/redis/ClusterPipelineProvider.scala
@@ -16,10 +16,14 @@
  */
 package feast.ingestion.stores.redis
 
+import feast.ingestion.errorhanders.RetryStrategy
+import redis.clients.jedis.exceptions.JedisClusterOperationException
 import redis.clients.jedis.{ClusterPipeline, DefaultJedisClientConfig, HostAndPort}
 import redis.clients.jedis.providers.ClusterConnectionProvider
 
 import scala.collection.JavaConverters._
+import scala.concurrent.duration.DurationInt
+import scala.util.{Failure, Success, Try}
 
 /**
   * Provide pipeline for Redis cluster.
@@ -31,7 +35,17 @@ case class ClusterPipelineProvider(endpoint: RedisEndpoint) extends PipelineProv
     .builder()
     .password(endpoint.password)
     .build()
-  val provider = new ClusterConnectionProvider(nodes, DEFAULT_CLIENT_CONFIG)
+  val MAX_RECONNECTION_ATTEMPT = 2
+  val RETRY_INTERVAL           = 2.seconds
+  val provider                 = RetryStrategy.fixedBackOff(RETRY_INTERVAL, MAX_RECONNECTION_ATTEMPT)(getProvider)
+
+  def getProvider: Either[JedisClusterOperationException, ClusterConnectionProvider] = {
+    Try { new ClusterConnectionProvider(nodes, DEFAULT_CLIENT_CONFIG) } match {
+      case Success(provider)                          => Right(provider)
+      case Failure(e: JedisClusterOperationException) => Left(e)
+      case Failure(e)                                 => throw e
+    }
+  }
 
   /**
     * @return a cluster pipeline

diff --git a/spark/ingestion/src/test/scala/feast/ingestion/errorhandlers/RetryStrategySpec.scala b/spark/ingestion/src/test/scala/feast/ingestion/errorhandlers/RetryStrategySpec.scala
@@ -0,0 +1,68 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ * Copyright 2018-2022 The Feast Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package feast.ingestion.errorhandlers
+
+import feast.ingestion.UnitSpec
+import feast.ingestion.errorhanders.RetryStrategy
+
+import scala.concurrent.duration.DurationInt
+import scala.util.{Failure, Try}
+
+class RetryStrategySpec extends UnitSpec {
+
+  case class SomeException(message: String) extends Exception
+
+  "function that always succeed" should "not be retried" in {
+    var i = 0
+
+    def alwaysSucceedFunc: Either[SomeException, Int] = {
+      i += 1
+      Right(0)
+    }
+    val result = RetryStrategy.fixedBackOff(1.second, 2)(alwaysSucceedFunc)
+    i should be(1)
+    result should be(0)
+  }
+
+  "function that always failed" should "be retried up to the maximum attempt and throw exception" in {
+    var i = 0
+
+    def alwaysFailFunc: Either[SomeException, Int] = {
+      i += 1
+      Left(SomeException("error"))
+    }
+    val result = Try { RetryStrategy.fixedBackOff(10.milli, 2)(alwaysFailFunc) }
+    i should be(3)
+    result should matchPattern { case Failure(_: SomeException) => }
+  }
+
+  "function that succeeds when retried" should "immediately return value when succeeded" in {
+    var i = 0
+
+    def succeedWhenRetriedFunc: Either[SomeException, Int] = {
+      i += 1
+      if (i < 2) {
+        Left(SomeException("error"))
+      } else {
+        Right(0)
+      }
+    }
+    val result = RetryStrategy.fixedBackOff(1.second, 2)(succeedWhenRetriedFunc)
+    i should be(2)
+    result should be(0)
+  }
+}