[SPARK-8005][SQL] Input file name

Users can now get the file name of the partition being read in. A thread local variable is in `SQLNewHadoopRDD` and is set when the partition is computed. `SQLNewHadoopRDD` is moved to core so that the catalyst package can reach it.

This supports:

`df.select(inputFileName())`

and

`sqlContext.sql("select input_file_name() from table")`

Author: Joseph Batchik <josephbatchik@gmail.com>

Closes #7743 from JDrit/input_file_name and squashes the following commits:

abb8609 [Joseph Batchik] fixed failing test and changed the default value to be an empty string
d2f323d [Joseph Batchik] updates per review
102061f [Joseph Batchik] updates per review
75313f5 [Joseph Batchik] small fixes
c7f7b5a [Joseph Batchik] addeding input file name to Spark SQL

4 files changed, 57 insertions, 1 deletions

diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/FunctionRegistry.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/FunctionRegistry.scala
index 372f80d4a8..378df4f57d 100644
--- a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/FunctionRegistry.scala
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/FunctionRegistry.scala
@@ -230,7 +230,8 @@ object FunctionRegistry {
     expression[Sha1]("sha"),
     expression[Sha1]("sha1"),
     expression[Sha2]("sha2"),
-    expression[SparkPartitionID]("spark_partition_id")
+    expression[SparkPartitionID]("spark_partition_id"),
+    expression[InputFileName]("input_file_name")
   )
 
   val builtin: FunctionRegistry = {
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/InputFileName.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/InputFileName.scala
new file mode 100644
index 0000000000..1e74f71695
--- /dev/null
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/InputFileName.scala
@@ -0,0 +1,49 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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
+ *
+ *    http://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 org.apache.spark.sql.catalyst.expressions
+
+import org.apache.spark.rdd.SqlNewHadoopRDD
+import org.apache.spark.sql.catalyst.InternalRow
+import org.apache.spark.sql.catalyst.expressions.codegen.{GeneratedExpressionCode, CodeGenContext}
+import org.apache.spark.sql.types.{DataType, StringType}
+import org.apache.spark.unsafe.types.UTF8String
+
+/**
+ * Expression that returns the name of the current file being read in using [[SqlNewHadoopRDD]]
+ */
+case class InputFileName() extends LeafExpression with Nondeterministic {
+
+  override def nullable: Boolean = true
+
+  override def dataType: DataType = StringType
+
+  override val prettyName = "INPUT_FILE_NAME"
+
+  override protected def initInternal(): Unit = {}
+
+  override protected def evalInternal(input: InternalRow): UTF8String = {
+    SqlNewHadoopRDD.getInputFileName()
+  }
+
+  override def genCode(ctx: CodeGenContext, ev: GeneratedExpressionCode): String = {
+    ev.isNull = "false"
+    s"final ${ctx.javaType(dataType)} ${ev.primitive} = " +
+      "org.apache.spark.rdd.SqlNewHadoopRDD.getInputFileName();"
+  }
+
+}
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/SparkPartitionID.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/SparkPartitionID.scala
index 3f6480bbf0..4b1772a2de 100644
--- a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/SparkPartitionID.scala
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/SparkPartitionID.scala
@@ -34,6 +34,8 @@ private[sql] case class SparkPartitionID() extends LeafExpression with Nondeterm
 
   @transient private[this] var partitionId: Int = _
 
+  override val prettyName = "SPARK_PARTITION_ID"
+
   override protected def initInternal(): Unit = {
     partitionId = TaskContext.getPartitionId()
   }
diff --git a/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/expressions/NondeterministicSuite.scala b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/expressions/NondeterministicSuite.scala
index 82894822ab..bf1c930c0b 100644
--- a/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/expressions/NondeterministicSuite.scala
+++ b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/expressions/NondeterministicSuite.scala
@@ -27,4 +27,8 @@ class NondeterministicSuite extends SparkFunSuite with ExpressionEvalHelper {
   test("SparkPartitionID") {
     checkEvaluation(SparkPartitionID(), 0)
   }
+
+  test("InputFileName") {
+    checkEvaluation(InputFileName(), "")
+  }
 }