[SPARK-24811][SQL]Avro: add new function from_avro and to_avro

external/avro/pom.xml

@@ -61,6 +61,11 @@
       <type>test-jar</type>
       <scope>test</scope>
     </dependency>
+    <dependency>
+      <groupId>org.scalacheck</groupId>
+      <artifactId>scalacheck_${scala.binary.version}</artifactId>
+      <scope>test</scope>
+    </dependency>
     <dependency>
       <groupId>org.apache.spark</groupId>
       <artifactId>spark-tags_${scala.binary.version}</artifactId>

external/avro/src/main/scala/org/apache/spark/sql/avro/AvroDataToCatalyst.scala

@@ -0,0 +1,68 @@
+/*
+ * 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
+
+import org.apache.avro.Schema
+import org.apache.avro.generic.GenericDatumReader
+import org.apache.avro.io.{BinaryDecoder, DecoderFactory}
+
+import org.apache.spark.sql.avro.{AvroDeserializer, SchemaConverters}
+import org.apache.spark.sql.catalyst.expressions.{ExpectsInputTypes, Expression, UnaryExpression}
+import org.apache.spark.sql.catalyst.expressions.codegen.{CodegenContext, CodeGenerator, ExprCode}
+import org.apache.spark.sql.types.{AbstractDataType, BinaryType, DataType}
+
+case class AvroDataToCatalyst(child: Expression, jsonFormatSchema: String)
+  extends UnaryExpression with ExpectsInputTypes {
+
+  override def inputTypes: Seq[AbstractDataType] = Seq(BinaryType)
+
+  override lazy val dataType: DataType = SchemaConverters.toSqlType(avroSchema).dataType
+
+  override def nullable: Boolean = true
+
+  @transient private lazy val avroSchema = new Schema.Parser().parse(jsonFormatSchema)
+
+  @transient private lazy val reader = new GenericDatumReader[Any](avroSchema)
+
+  @transient private lazy val deserializer = new AvroDeserializer(avroSchema, dataType)
+
+  @transient private var decoder: BinaryDecoder = _
+
+  @transient private var result: Any = _
+
+  override def nullSafeEval(input: Any): Any = {
+    val binary = input.asInstanceOf[Array[Byte]]
+    decoder = DecoderFactory.get().binaryDecoder(binary, 0, binary.length, decoder)
+    result = reader.read(result, decoder)
+    deserializer.deserialize(result)
+  }
+
+  override def simpleString: String = {
+    s"from_avro(${child.sql}, ${dataType.simpleString})"
+  }
+
+  override def sql: String = {
+    s"from_avro(${child.sql}, ${dataType.catalogString})"
+  }
+
+  override protected def doGenCode(ctx: CodegenContext, ev: ExprCode): ExprCode = {
+    val expr = ctx.addReferenceObj("this", this)
+    defineCodeGen(ctx, ev, input =>
+      s"(${CodeGenerator.boxedType(dataType)})$expr.nullSafeEval($input)")
+  }
+}

external/avro/src/main/scala/org/apache/spark/sql/avro/CatalystDataToAvro.scala

@@ -0,0 +1,69 @@
+/*
+ * 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
+
+import java.io.ByteArrayOutputStream
+
+import org.apache.avro.generic.GenericDatumWriter
+import org.apache.avro.io.{BinaryEncoder, EncoderFactory}
+
+import org.apache.spark.sql.avro.{AvroSerializer, SchemaConverters}
+import org.apache.spark.sql.catalyst.expressions.{Expression, UnaryExpression}
+import org.apache.spark.sql.catalyst.expressions.codegen.{CodegenContext, CodeGenerator, ExprCode}
+import org.apache.spark.sql.types.{BinaryType, DataType}
+
+case class CatalystDataToAvro(child: Expression) extends UnaryExpression {
+
+  override def dataType: DataType = BinaryType
+
+  @transient private lazy val avroType =
+    SchemaConverters.toAvroType(child.dataType, child.nullable)
+
+  @transient private lazy val serializer =
+    new AvroSerializer(child.dataType, avroType, child.nullable)
+
+  @transient private lazy val writer =
+    new GenericDatumWriter[Any](avroType)
+
+  @transient private var encoder: BinaryEncoder = _
+
+  @transient private lazy val out = new ByteArrayOutputStream
+
+  override def nullSafeEval(input: Any): Any = {
+    out.reset()
+    encoder = EncoderFactory.get().directBinaryEncoder(out, encoder)
+    val avroData = serializer.serialize(input)
+    writer.write(avroData, encoder)
+    encoder.flush()
+    out.toByteArray
+  }
+
+  override def simpleString: String = {
+    s"to_avro(${child.sql}, ${child.dataType.simpleString})"
+  }
+
+  override def sql: String = {
+    s"to_avro(${child.sql}, ${child.dataType.catalogString})"
+  }
+
+  override protected def doGenCode(ctx: CodegenContext, ev: ExprCode): ExprCode = {
+    val expr = ctx.addReferenceObj("this", this)
+    defineCodeGen(ctx, ev, input =>
+      s"(byte[]) $expr.nullSafeEval($input)")
+  }
+}

external/avro/src/main/scala/org/apache/spark/sql/avro/package.scala

@@ -17,6 +17,10 @@
 
 package org.apache.spark.sql
 
+import org.apache.avro.Schema
+
+import org.apache.spark.annotation.Experimental
+
 package object avro {
   /**
    * Adds a method, `avro`, to DataFrameWriter that allows you to write avro files using
@@ -36,4 +40,31 @@ package object avro {
     @scala.annotation.varargs
     def avro(sources: String*): DataFrame = reader.format("avro").load(sources: _*)
   }
+
+  /**
+   * Converts a binary column of avro format into its corresponding catalyst value. The specified
+   * schema must match the read data, otherwise the behavior is undefined: it may fail or return
+   * arbitrary result.
+   *
+   * @param data the binary column.
+   * @param jsonFormatSchema the avro schema in JSON string format.
+   *
+   * @since 2.4.0
+   */
+  @Experimental
+  def from_avro(data: Column, jsonFormatSchema: String): Column = {
+    new Column(AvroDataToCatalyst(data.expr, jsonFormatSchema))
+  }
+
+  /**
+   * Converts a column into binary of avro format.
+   *
+   * @param data the data column.
+   *
+   * @since 2.4.0
+   */
+  @Experimental
+  def to_avro(data: Column): Column = {
+    new Column(CatalystDataToAvro(data.expr))
+  }
 }

external/avro/src/test/resources/log4j.properties

@@ -15,35 +15,14 @@
 # limitations under the License.
 #
 
-# Set everything to be logged to the file core/target/unit-tests.log
-log4j.rootLogger=DEBUG, CA, FA
+# Set everything to be logged to the file target/unit-tests.log
+log4j.rootCategory=INFO, file
+log4j.appender.file=org.apache.log4j.FileAppender
+log4j.appender.file.append=true
+log4j.appender.file.file=target/unit-tests.log
+log4j.appender.file.layout=org.apache.log4j.PatternLayout
+log4j.appender.file.layout.ConversionPattern=%d{yy/MM/dd HH:mm:ss.SSS} %t %p %c{1}: %m%n
 
-#Console Appender
-log4j.appender.CA=org.apache.log4j.ConsoleAppender
-log4j.appender.CA.layout=org.apache.log4j.PatternLayout
-log4j.appender.CA.layout.ConversionPattern=%d{HH:mm:ss.SSS} %p %c: %m%n
-log4j.appender.CA.Threshold = WARN
+# Ignore messages below warning level from Jetty, because it's a bit verbose
+log4j.logger.org.spark-project.jetty=WARN
 
-
-#File Appender
-log4j.appender.FA=org.apache.log4j.FileAppender
-log4j.appender.FA.append=false
-log4j.appender.FA.file=target/unit-tests.log
-log4j.appender.FA.layout=org.apache.log4j.PatternLayout
-log4j.appender.FA.layout.ConversionPattern=%d{HH:mm:ss.SSS} %t %p %c{1}: %m%n
-
-# Set the logger level of File Appender to WARN
-log4j.appender.FA.Threshold = INFO
-
-# Some packages are noisy for no good reason.
-log4j.additivity.parquet.hadoop.ParquetRecordReader=false
-log4j.logger.parquet.hadoop.ParquetRecordReader=OFF
-
-log4j.additivity.org.apache.hadoop.hive.serde2.lazy.LazyStruct=false
-log4j.logger.org.apache.hadoop.hive.serde2.lazy.LazyStruct=OFF
-
-log4j.additivity.org.apache.hadoop.hive.metastore.RetryingHMSHandler=false
-log4j.logger.org.apache.hadoop.hive.metastore.RetryingHMSHandler=OFF
-
-log4j.additivity.hive.ql.metadata.Hive=false
-log4j.logger.hive.ql.metadata.Hive=OFF