[SPARK-17980][SQL] Fix refreshByPath for converted Hive tables

## What changes were proposed in this pull request?

There was a bug introduced in apache#14690 which broke refreshByPath with converted hive tables (though, it turns out it was very difficult to refresh converted hive tables anyways, since you had to specify the exact path of one of the partitions).

This changes refreshByPath to invalidate by prefix instead of exact match, and fixes the issue.

cc sameeragarwal for refreshByPath changes
mallman

## How was this patch tested?

Extended unit test.

Author: Eric Liang <[email protected]>

Closes apache#15521 from ericl/fix-caching.

sql/core/src/main/scala/org/apache/spark/sql/catalog/Catalog.scala

@@ -343,7 +343,8 @@ abstract class Catalog {
 
   /**
    * Invalidate and refresh all the cached data (and the associated metadata) for any dataframe that
-   * contains the given data source path.
+   * contains the given data source path. Path matching is by prefix, i.e. "/" would invalidate
+   * everything that is cached.
    *
    * @since 2.0.0
    */

sql/core/src/main/scala/org/apache/spark/sql/execution/CacheManager.scala

@@ -185,9 +185,10 @@ class CacheManager extends Logging {
     plan match {
       case lr: LogicalRelation => lr.relation match {
         case hr: HadoopFsRelation =>
+          val prefixToInvalidate = qualifiedPath.toString
           val invalidate = hr.location.rootPaths
-            .map(_.makeQualified(fs.getUri, fs.getWorkingDirectory))
-            .contains(qualifiedPath)
+            .map(_.makeQualified(fs.getUri, fs.getWorkingDirectory).toString)
+            .exists(_.startsWith(prefixToInvalidate))
           if (invalidate) hr.location.refresh()
           invalidate
         case _ => false

sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/TableFileCatalog.scala

@@ -48,13 +48,18 @@ class TableFileCatalog(
 
   private val baseLocation = catalogTable.storage.locationUri
 
+  // Populated on-demand by calls to cachedAllPartitions
+  private var cachedAllPartitions: ListingFileCatalog = null
+
   override def rootPaths: Seq[Path] = baseLocation.map(new Path(_)).toSeq
 
   override def listFiles(filters: Seq[Expression]): Seq[PartitionDirectory] = {
     filterPartitions(filters).listFiles(Nil)
   }
 
-  override def refresh(): Unit = {}
+  override def refresh(): Unit = synchronized {
+    cachedAllPartitions = null
+  }
 
   /**
    * Returns a [[ListingFileCatalog]] for this table restricted to the subset of partitions
@@ -64,7 +69,7 @@ class TableFileCatalog(
    */
   def filterPartitions(filters: Seq[Expression]): ListingFileCatalog = {
     if (filters.isEmpty) {
-      cachedAllPartitions
+      allPartitions
     } else {
       filterPartitions0(filters)
     }
@@ -89,9 +94,14 @@ class TableFileCatalog(
   }
 
   // Not used in the hot path of queries when metastore partition pruning is enabled
-  lazy val cachedAllPartitions: ListingFileCatalog = filterPartitions0(Nil)
+  def allPartitions: ListingFileCatalog = synchronized {
+    if (cachedAllPartitions == null) {
+      cachedAllPartitions = filterPartitions0(Nil)
+    }
+    cachedAllPartitions
+  }
 
-  override def inputFiles: Array[String] = cachedAllPartitions.inputFiles
+  override def inputFiles: Array[String] = allPartitions.inputFiles
 }
 
 /**

sql/hive/src/main/scala/org/apache/spark/sql/hive/HiveMetastoreCatalog.scala

@@ -235,7 +235,7 @@ private[hive] class HiveMetastoreCatalog(sparkSession: SparkSession) extends Log
           if (lazyPruningEnabled) {
             catalog
           } else {
-            catalog.cachedAllPartitions
+            catalog.allPartitions
           }
         }
         val partitionSchemaColumnNames = partitionSchema.map(_.name.toLowerCase).toSet

sql/hive/src/test/scala/org/apache/spark/sql/hive/HiveMetadataCacheSuite.scala

@@ -80,9 +80,13 @@ class HiveMetadataCacheSuite extends QueryTest with SQLTestUtils with TestHiveSi
             val df = spark.sql("select * from test")
             assert(sql("select * from test").count() == 5)
 
+            def deleteRandomFile(): Unit = {
+              val p = new Path(spark.table("test").inputFiles.head)
+              assert(p.getFileSystem(hiveContext.sessionState.newHadoopConf()).delete(p, true))
+            }
+
             // Delete a file, then assert that we tried to read it. This means the table was cached.
-            val p = new Path(spark.table("test").inputFiles.head)
-            assert(p.getFileSystem(hiveContext.sessionState.newHadoopConf()).delete(p, true))
+            deleteRandomFile()
             val e = intercept[SparkException] {
               sql("select * from test").count()
             }
@@ -91,6 +95,19 @@ class HiveMetadataCacheSuite extends QueryTest with SQLTestUtils with TestHiveSi
             // Test refreshing the cache.
             spark.catalog.refreshTable("test")
             assert(sql("select * from test").count() == 4)
+            assert(spark.table("test").inputFiles.length == 4)
+
+            // Test refresh by path separately since it goes through different code paths than
+            // refreshTable does.
+            deleteRandomFile()
+            spark.catalog.cacheTable("test")
+            spark.catalog.refreshByPath("/some-invalid-path")  // no-op
+            val e2 = intercept[SparkException] {
+              sql("select * from test").count()
+            }
+            assert(e2.getMessage.contains("FileNotFoundException"))
+            spark.catalog.refreshByPath(dir.getAbsolutePath)
+            assert(sql("select * from test").count() == 3)
           }
         }
       }