From 47b3848bf54520c5e42ff545da30d5438af60c88 Mon Sep 17 00:00:00 2001
From: Reynold Xin <rxin@apache.org>
Date: Sat, 9 Aug 2014 23:28:11 -0700
Subject: [PATCH 1/3] [SPARK-2953] Allow using short names for io compression
 codecs

Instead of requiring "org.apache.spark.io.LZ4CompressionCodec", it is easier for users if Spark just accepts "lz4", "lzf", "snappy".
---
 .../org/apache/spark/io/CompressionCodec.scala | 11 +++++++++--
 .../spark/io/CompressionCodecSuite.scala       | 18 ++++++++++++++++++
 2 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/core/src/main/scala/org/apache/spark/io/CompressionCodec.scala b/core/src/main/scala/org/apache/spark/io/CompressionCodec.scala
index 1b66218d86dd9..ef9c43ecf14f6 100644
--- a/core/src/main/scala/org/apache/spark/io/CompressionCodec.scala
+++ b/core/src/main/scala/org/apache/spark/io/CompressionCodec.scala
@@ -46,17 +46,24 @@ trait CompressionCodec {
 
 
 private[spark] object CompressionCodec {
+
+  private val shortCompressionCodecNames = Map(
+    "lz4" -> classOf[LZ4CompressionCodec].getName,
+    "lzf" -> classOf[LZFCompressionCodec].getName,
+    "snappy" -> classOf[SnappyCompressionCodec].getName)
+
   def createCodec(conf: SparkConf): CompressionCodec = {
     createCodec(conf, conf.get("spark.io.compression.codec", DEFAULT_COMPRESSION_CODEC))
   }
 
   def createCodec(conf: SparkConf, codecName: String): CompressionCodec = {
-    val ctor = Class.forName(codecName, true, Utils.getContextOrSparkClassLoader)
+    val codecClass = shortCompressionCodecNames.getOrElse(codecName.toLowerCase, codecName)
+    val ctor = Class.forName(codecClass, true, Utils.getContextOrSparkClassLoader)
       .getConstructor(classOf[SparkConf])
     ctor.newInstance(conf).asInstanceOf[CompressionCodec]
   }
 
-  val DEFAULT_COMPRESSION_CODEC = classOf[SnappyCompressionCodec].getName
+  val DEFAULT_COMPRESSION_CODEC = "snappy"
 }
 
 
diff --git a/core/src/test/scala/org/apache/spark/io/CompressionCodecSuite.scala b/core/src/test/scala/org/apache/spark/io/CompressionCodecSuite.scala
index 3f882a724b047..25be7f25c21bb 100644
--- a/core/src/test/scala/org/apache/spark/io/CompressionCodecSuite.scala
+++ b/core/src/test/scala/org/apache/spark/io/CompressionCodecSuite.scala
@@ -56,15 +56,33 @@ class CompressionCodecSuite extends FunSuite {
     testCodec(codec)
   }
 
+  test("lz4 compression codec short form") {
+    val codec = CompressionCodec.createCodec(conf, "lz4")
+    assert(codec.getClass === classOf[LZ4CompressionCodec])
+    testCodec(codec)
+  }
+
   test("lzf compression codec") {
     val codec = CompressionCodec.createCodec(conf, classOf[LZFCompressionCodec].getName)
     assert(codec.getClass === classOf[LZFCompressionCodec])
     testCodec(codec)
   }
 
+  test("lzf compression codec short form") {
+    val codec = CompressionCodec.createCodec(conf, "lzf")
+    assert(codec.getClass === classOf[LZFCompressionCodec])
+    testCodec(codec)
+  }
+
   test("snappy compression codec") {
     val codec = CompressionCodec.createCodec(conf, classOf[SnappyCompressionCodec].getName)
     assert(codec.getClass === classOf[SnappyCompressionCodec])
     testCodec(codec)
   }
+
+  test("snappy compression codec short form") {
+    val codec = CompressionCodec.createCodec(conf, "snappy")
+    assert(codec.getClass === classOf[SnappyCompressionCodec])
+    testCodec(codec)
+  }
 }

From 63f78eec8f7e6a757e9a364a1cc0dcb93dd4bdda Mon Sep 17 00:00:00 2001
From: Reynold Xin <rxin@apache.org>
Date: Sat, 9 Aug 2014 23:31:00 -0700
Subject: [PATCH 2/3] Updated configuration documentation.

---
 docs/configuration.md | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/docs/configuration.md b/docs/configuration.md
index 617a72a021f6e..9716512442275 100644
--- a/docs/configuration.md
+++ b/docs/configuration.md
@@ -373,12 +373,12 @@ Apart from these, the following properties are also available, and may be useful
 </tr>
 <tr>
   <td><code>spark.io.compression.codec</code></td>
-  <td>org.apache.spark.io.<br />SnappyCompressionCodec</td>
+  <td>snappy</td>
   <td>
     The codec used to compress internal data such as RDD partitions and shuffle outputs.
     By default, Spark provides three codecs:  <code>org.apache.spark.io.LZ4CompressionCodec</code>,
     <code>org.apache.spark.io.LZFCompressionCodec</code>,
-    and <code>org.apache.spark.io.SnappyCompressionCodec</code>.
+    and <code>org.apache.spark.io.SnappyCompressionCodec</code>. You can also use the short form: <code>lz4</code>, <code>lzf</code>, and <code>snappy</code>.
   </td>
 </tr>
 <tr>

From 9f50962366901f81a9c7a83a3742e37e3762c3f4 Mon Sep 17 00:00:00 2001
From: Reynold Xin <rxin@apache.org>
Date: Tue, 12 Aug 2014 21:47:52 -0700
Subject: [PATCH 3/3] Specify short-form compression codec names first.

---
 docs/configuration.md | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/docs/configuration.md b/docs/configuration.md
index 9716512442275..8136bd62ab6af 100644
--- a/docs/configuration.md
+++ b/docs/configuration.md
@@ -375,10 +375,12 @@ Apart from these, the following properties are also available, and may be useful
   <td><code>spark.io.compression.codec</code></td>
   <td>snappy</td>
   <td>
-    The codec used to compress internal data such as RDD partitions and shuffle outputs.
-    By default, Spark provides three codecs:  <code>org.apache.spark.io.LZ4CompressionCodec</code>,
+    The codec used to compress internal data such as RDD partitions and shuffle outputs. By default,
+    Spark provides three codecs: <code>lz4</code>, <code>lzf</code>, and <code>snappy</code>. You
+    can also use fully qualified class names to specify the codec, e.g.
+    <code>org.apache.spark.io.LZ4CompressionCodec</code>,
     <code>org.apache.spark.io.LZFCompressionCodec</code>,
-    and <code>org.apache.spark.io.SnappyCompressionCodec</code>. You can also use the short form: <code>lz4</code>, <code>lzf</code>, and <code>snappy</code>.
+    and <code>org.apache.spark.io.SnappyCompressionCodec</code>.
   </td>
 </tr>
 <tr>