Merge pull request #2 from rore/master

Adding readme about HBaseRawSource

1 files changed, 58 insertions, 37 deletions

diff --git a/src/main/scala/parallelai/spyglass/hbase/HBaseRawSource.scala b/src/main/scala/parallelai/spyglass/hbase/HBaseRawSource.scala
index 1fc6f7d..bbc205b 100644
--- a/src/main/scala/parallelai/spyglass/hbase/HBaseRawSource.scala
+++ b/src/main/scala/parallelai/spyglass/hbase/HBaseRawSource.scala
@@ -18,45 +18,66 @@ import java.io.ByteArrayOutputStream
 import java.io.DataOutputStream
 
 object HBaseRawSource {
-  def convertScanToString(scan: Scan) = {
-    val out = new ByteArrayOutputStream();
-    val dos = new DataOutputStream(out);
-    scan.write(dos);
-    Base64.encodeBytes(out.toByteArray());
-  }
+	/**
+	 * Converts a scan object to a base64 string that can be passed to HBaseRawSource
+	 * @param scan
+	 * @return base64 string representation
+	 */
+	def convertScanToString(scan: Scan) = {
+		val out = new ByteArrayOutputStream();
+		val dos = new DataOutputStream(out);
+		scan.write(dos);
+		Base64.encodeBytes(out.toByteArray());
+	}
 }
+
+
+/**
+ * @author Rotem Hermon
+ *
+ * HBaseRawSource is a scalding source that passes the original row (Result) object to the 
+ * mapper for customized processing.
+ * 
+ * @param	tableName	The name of the HBase table to read
+ * @param	quorumNames	HBase quorum
+ * @param	familyNames	Column families to get (source, if null will get all) or update to (sink)
+ * @param	writeNulls	Should the sink write null values. default = true. If false, null columns will not be written
+ * @param	base64Scan	An optional base64 encoded scan object 
+ * @param	sinkMode	If REPLACE the output table will be deleted before writing to	
+ * 
+ */
 class HBaseRawSource(
-  tableName: String,
-  quorumNames: String = "localhost",
-  familyNames: Array[String],
-  writeNulls: Boolean = true,
-  base64Scan:String = null,
-  sinkMode: SinkMode = null) extends Source {
+	tableName: String,
+	quorumNames: String = "localhost",
+	familyNames: Array[String],
+	writeNulls: Boolean = true,
+	base64Scan: String = null,
+	sinkMode: SinkMode = null) extends Source {
 
-  override val hdfsScheme = new HBaseRawScheme(familyNames, writeNulls)
-    .asInstanceOf[Scheme[JobConf, RecordReader[_, _], OutputCollector[_, _], _, _]]
+	override val hdfsScheme = new HBaseRawScheme(familyNames, writeNulls)
+		.asInstanceOf[Scheme[JobConf, RecordReader[_, _], OutputCollector[_, _], _, _]]
 
-  override def createTap(readOrWrite: AccessMode)(implicit mode: Mode): Tap[_, _, _] = {
-    val hBaseScheme = hdfsScheme match {
-      case hbase: HBaseRawScheme => hbase
-      case _ => throw new ClassCastException("Failed casting from Scheme to HBaseRawScheme")
-    }
-    mode match {
-      case hdfsMode @ Hdfs(_, _) => readOrWrite match {
-        case Read => {
-          new HBaseRawTap(quorumNames, tableName, hBaseScheme, base64Scan, sinkMode match {
-            case null => SinkMode.KEEP
-            case _ => sinkMode
-          }).asInstanceOf[Tap[_,_,_]]
-        }
-        case Write => {
-          new HBaseRawTap(quorumNames, tableName, hBaseScheme, base64Scan, sinkMode match {
-            case null => SinkMode.UPDATE
-            case _ => sinkMode
-          }).asInstanceOf[Tap[_,_,_]]
-        }
-      }
-      case _ => super.createTap(readOrWrite)(mode)
-    }
-  }
+	override def createTap(readOrWrite: AccessMode)(implicit mode: Mode): Tap[_, _, _] = {
+		val hBaseScheme = hdfsScheme match {
+			case hbase: HBaseRawScheme => hbase
+			case _ => throw new ClassCastException("Failed casting from Scheme to HBaseRawScheme")
+		}
+		mode match {
+			case hdfsMode @ Hdfs(_, _) => readOrWrite match {
+				case Read => {
+					new HBaseRawTap(quorumNames, tableName, hBaseScheme, base64Scan, sinkMode match {
+						case null => SinkMode.KEEP
+						case _ => sinkMode
+					}).asInstanceOf[Tap[_, _, _]]
+				}
+				case Write => {
+					new HBaseRawTap(quorumNames, tableName, hBaseScheme, base64Scan, sinkMode match {
+						case null => SinkMode.UPDATE
+						case _ => sinkMode
+					}).asInstanceOf[Tap[_, _, _]]
+				}
+			}
+			case _ => super.createTap(readOrWrite)(mode)
+		}
+	}
 }