[SPARK-18671][SS][TEST] Added tests to ensure stability of that all Structured...

[SPARK-18671][SS][TEST] Added tests to ensure stability of that all Structured Streaming log formats

## What changes were proposed in this pull request?

To be able to restart StreamingQueries across Spark version, we have already made the logs (offset log, file source log, file sink log) use json. We should added tests with actual json files in the Spark such that any incompatible changes in reading the logs is immediately caught. This PR add tests for FileStreamSourceLog, FileStreamSinkLog, and OffsetSeqLog.

## How was this patch tested?
new unit tests

Author: Tathagata Das <tathagata.das1565@gmail.com>

Closes #16128 from tdas/SPARK-18671.

dev/.rat-excludes

@@ -102,3 +102,4 @@ org.apache.spark.scheduler.ExternalClusterManager
 .Rbuildignore
 org.apache.spark.deploy.yarn.security.ServiceCredentialProvider
 spark-warehouse
+structured-streaming/*

external/kafka-0-10-sql/src/main/scala/org/apache/spark/sql/kafka010/JsonUtils.scala

@@ -81,7 +81,14 @@ private object JsonUtils {
    */
   def partitionOffsets(partitionOffsets: Map[TopicPartition, Long]): String = {
     val result = new HashMap[String, HashMap[Int, Long]]()
-    partitionOffsets.foreach { case (tp, off) =>
+    implicit val ordering = new Ordering[TopicPartition] {
+      override def compare(x: TopicPartition, y: TopicPartition): Int = {
+        Ordering.Tuple2[String, Int].compare((x.topic, x.partition), (y.topic, y.partition))
+      }
+    }
+    val partitions = partitionOffsets.keySet.toSeq.sorted  // sort for more determinism
+    partitions.foreach { tp =>
+        val off = partitionOffsets(tp)
         val parts = result.getOrElse(tp.topic, new HashMap[Int, Long])
         parts += tp.partition -> off
         result += tp.topic -> parts

external/kafka-0-10-sql/src/test/scala/org/apache/spark/sql/kafka010/KafkaSourceOffsetSuite.scala

@@ -89,4 +89,16 @@ class KafkaSourceOffsetSuite extends OffsetSuite with SharedSQLContext {
         Array(0 -> batch0Serialized, 1 -> batch1Serialized))
     }
   }
+
+  test("read Spark 2.1.0 log format") {
+    val offset = readFromResource("kafka-source-offset-version-2.1.0.txt")
+    assert(KafkaSourceOffset(offset) ===
+      KafkaSourceOffset(("topic1", 0, 456L), ("topic1", 1, 789L), ("topic2", 0, 0L)))
+  }
+
+  private def readFromResource(file: String): SerializedOffset = {
+    import scala.io.Source
+    val str = Source.fromFile(getClass.getResource(s"/structured-streaming/$file").toURI).mkString
+    SerializedOffset(str)
+  }
 }

sql/core/src/test/resources/structured-streaming/file-sink-log-version-2.1.0/7.compact

+v1
+{"path":"/a/b/0","size":1,"isDir":false,"modificationTime":1,"blockReplication":1,"blockSize":100,"action":"add"}
+{"path":"/a/b/1","size":100,"isDir":false,"modificationTime":100,"blockReplication":1,"blockSize":100,"action":"add"}
+{"path":"/a/b/2","size":200,"isDir":false,"modificationTime":200,"blockReplication":1,"blockSize":100,"action":"add"}
+{"path":"/a/b/3","size":300,"isDir":false,"modificationTime":300,"blockReplication":1,"blockSize":100,"action":"add"}
+{"path":"/a/b/4","size":400,"isDir":false,"modificationTime":400,"blockReplication":1,"blockSize":100,"action":"add"}
+{"path":"/a/b/5","size":500,"isDir":false,"modificationTime":500,"blockReplication":1,"blockSize":100,"action":"add"}
+{"path":"/a/b/6","size":600,"isDir":false,"modificationTime":600,"blockReplication":1,"blockSize":100,"action":"add"}
+{"path":"/a/b/7","size":700,"isDir":false,"modificationTime":700,"blockReplication":1,"blockSize":100,"action":"add"}

sql/core/src/test/resources/structured-streaming/file-sink-log-version-2.1.0/8

+v1
+{"path":"/a/b/8","size":800,"isDir":false,"modificationTime":800,"blockReplication":1,"blockSize":100,"action":"add"}
+{"path":"/a/b/0","size":100,"isDir":false,"modificationTime":100,"blockReplication":1,"blockSize":100,"action":"delete"}

sql/core/src/test/resources/structured-streaming/file-sink-log-version-2.1.0/9

+v1
+{"path":"/a/b/9","size":900,"isDir":false,"modificationTime":900,"blockReplication":3,"blockSize":200,"action":"add"}

sql/core/src/test/resources/structured-streaming/file-source-log-version-2.1.0/2.compact

+v1
+{"path":"/a/b/0","timestamp":1480730949000,"batchId":0}
+{"path":"/a/b/1","timestamp":1480730950000,"batchId":1}
+{"path":"/a/b/2","timestamp":1480730950000,"batchId":2}

sql/core/src/test/resources/structured-streaming/file-source-log-version-2.1.0/3

+v1
+{"path":"/a/b/3","timestamp":1480730950000,"batchId":3}

sql/core/src/test/resources/structured-streaming/file-source-log-version-2.1.0/4

+v1
+{"path":"/a/b/4","timestamp":1480730951000,"batchId":4}

sql/core/src/test/resources/structured-streaming/file-source-offset-version-2.1.0.txt

+345

sql/core/src/test/resources/structured-streaming/kafka-source-offset-version-2.1.0.txt

+{"topic1":{"0":456,"1":789},"topic2":{"0":0}}

sql/core/src/test/resources/structured-streaming/offset-log-version-2.1.0/0

+v1
+{"batchWatermarkMs":0,"batchTimestampMs":1480981499528}
+0
+{"topic-0":{"0":1}}
\ No newline at end of file

sql/core/src/test/scala/org/apache/spark/sql/execution/streaming/FileStreamSinkLogSuite.scala

@@ -185,6 +185,21 @@ class FileStreamSinkLogSuite extends SparkFunSuite with SharedSQLContext {
     }
   }
 
+  test("read Spark 2.1.0 log format") {
+    assert(readFromResource("file-sink-log-version-2.1.0") === Seq(
+      // SinkFileStatus("/a/b/0", 100, false, 100, 1, 100, FileStreamSinkLog.ADD_ACTION), -> deleted
+      SinkFileStatus("/a/b/1", 100, false, 100, 1, 100, FileStreamSinkLog.ADD_ACTION),
+      SinkFileStatus("/a/b/2", 200, false, 200, 1, 100, FileStreamSinkLog.ADD_ACTION),
+      SinkFileStatus("/a/b/3", 300, false, 300, 1, 100, FileStreamSinkLog.ADD_ACTION),
+      SinkFileStatus("/a/b/4", 400, false, 400, 1, 100, FileStreamSinkLog.ADD_ACTION),
+      SinkFileStatus("/a/b/5", 500, false, 500, 1, 100, FileStreamSinkLog.ADD_ACTION),
+      SinkFileStatus("/a/b/6", 600, false, 600, 1, 100, FileStreamSinkLog.ADD_ACTION),
+      SinkFileStatus("/a/b/7", 700, false, 700, 1, 100, FileStreamSinkLog.ADD_ACTION),
+      SinkFileStatus("/a/b/8", 800, false, 800, 1, 100, FileStreamSinkLog.ADD_ACTION),
+      SinkFileStatus("/a/b/9", 900, false, 900, 3, 200, FileStreamSinkLog.ADD_ACTION)
+    ))
+  }
+
   /**
    * Create a fake SinkFileStatus using path and action. Most of tests don't care about other fields
    * in SinkFileStatus.
@@ -206,4 +221,10 @@ class FileStreamSinkLogSuite extends SparkFunSuite with SharedSQLContext {
       f(sinkLog)
     }
   }
+
+  private def readFromResource(dir: String): Seq[SinkFileStatus] = {
+    val input = getClass.getResource(s"/structured-streaming/$dir")
+    val log = new FileStreamSinkLog(FileStreamSinkLog.VERSION, spark, input.toString)
+    log.allFiles()
+  }
 }

sql/core/src/test/scala/org/apache/spark/sql/execution/streaming/OffsetSeqLogSuite.scala

@@ -69,4 +69,20 @@ class OffsetSeqLogSuite extends SparkFunSuite with SharedSQLContext {
         Array(0 -> batch0Serialized, 1 -> batch1Serialized))
     }
   }
+
+  test("read Spark 2.1.0 log format") {
+    val (batchId, offsetSeq) = readFromResource("offset-log-version-2.1.0")
+    assert(batchId === 0)
+    assert(offsetSeq.offsets === Seq(
+      Some(SerializedOffset("0")),
+      Some(SerializedOffset("""{"topic-0":{"0":1}}"""))
+    ))
+    assert(offsetSeq.metadata === Some(OffsetSeqMetadata(0L, 1480981499528L)))
+  }
+
+  private def readFromResource(dir: String): (Long, OffsetSeq) = {
+    val input = getClass.getResource(s"/structured-streaming/$dir")
+    val log = new OffsetSeqLog(spark, input.toString)
+    log.getLatest().get
+  }
 }

sql/core/src/test/scala/org/apache/spark/sql/streaming/FileStreamSourceSuite.scala

@@ -19,14 +19,13 @@ package org.apache.spark.sql.streaming
 
 import java.io.File
 
-import scala.collection.mutable
-
 import org.scalatest.PrivateMethodTester
 import org.scalatest.time.SpanSugar._
 
 import org.apache.spark.sql._
 import org.apache.spark.sql.catalyst.util._
 import org.apache.spark.sql.execution.streaming._
+import org.apache.spark.sql.execution.streaming.FileStreamSource.FileEntry
 import org.apache.spark.sql.internal.SQLConf
 import org.apache.spark.sql.test.SharedSQLContext
 import org.apache.spark.sql.types._
@@ -1022,6 +1021,33 @@ class FileStreamSourceSuite extends FileStreamSourceTest {
     val options = new FileStreamOptions(Map("maxfilespertrigger" -> "1"))
     assert(options.maxFilesPerTrigger == Some(1))
   }
+
+  test("FileStreamSource offset - read Spark 2.1.0 log format") {
+    val offset = readOffsetFromResource("file-source-offset-version-2.1.0.txt")
+    assert(LongOffset.convert(offset) === Some(LongOffset(345)))
+  }
+
+  test("FileStreamSourceLog - read Spark 2.1.0 log format") {
+    assert(readLogFromResource("file-source-log-version-2.1.0") === Seq(
+      FileEntry("/a/b/0", 1480730949000L, 0L),
+      FileEntry("/a/b/1", 1480730950000L, 1L),
+      FileEntry("/a/b/2", 1480730950000L, 2L),
+      FileEntry("/a/b/3", 1480730950000L, 3L),
+      FileEntry("/a/b/4", 1480730951000L, 4L)
+    ))
+  }
+
+  private def readLogFromResource(dir: String): Seq[FileEntry] = {
+    val input = getClass.getResource(s"/structured-streaming/$dir")
+    val log = new FileStreamSourceLog(FileStreamSourceLog.VERSION, spark, input.toString)
+    log.allFiles()
+  }
+
+  private def readOffsetFromResource(file: String): SerializedOffset = {
+    import scala.io.Source
+    val str = Source.fromFile(getClass.getResource(s"/structured-streaming/$file").toURI).mkString
+    SerializedOffset(str.trim)
+  }
 }
 
 class FileStreamSourceStressTestSuite extends FileStreamSourceTest {