[TOREE-408] Add support for hdfs and s3 to AddJar

Closes apache#125

Author: rdblue

kernel/src/main/scala/org/apache/toree/magic/builtin/AddJar.scala

@@ -18,17 +18,18 @@
 package org.apache.toree.magic.builtin
 
 import java.io.{File, PrintStream}
-import java.net.URL
+import java.net.{URL, URI}
 import java.nio.file.{Files, Paths}
-
 import org.apache.toree.magic._
 import org.apache.toree.magic.builtin.AddJar._
 import org.apache.toree.magic.dependencies._
 import org.apache.toree.utils.{ArgumentParsingSupport, DownloadSupport, LogLike, FileUtils}
 import com.typesafe.config.Config
+import org.apache.hadoop.fs.Path
 import org.apache.toree.plugins.annotations.Event
 
 object AddJar {
+  val HADOOP_FS_SCHEMES = Set("hdfs", "s3", "s3n", "file")
 
   private var jarDir:Option[String] = None
 
@@ -63,18 +64,18 @@ class AddJar
   private def printStream = new PrintStream(outputStream)
 
   /**
-   * Retrieves file name from URL.
+   * Retrieves file name from a URI.
    *
-   * @param location The remote location (URL) 
-   * @return The name of the remote URL, or an empty string if one does not exist
+   * @param location a URI
+   * @return The file name of the remote URI, or an empty string if one does not exist
    */
   def getFileFromLocation(location: String): String = {
-    val url = new URL(location)
-    val file = url.getFile.split("/")
-    if (file.length > 0) {
-        file.last
+    val uri = new URI(location)
+    val pathParts = uri.getPath.split("/")
+    if (pathParts.nonEmpty) {
+      pathParts.last
     } else {
-        ""
+      ""
     }
   }
 
@@ -122,10 +123,27 @@ class AddJar
       // Report beginning of download
       printStream.println(s"Starting download from $jarRemoteLocation")
 
-      downloadFile(
-        new URL(jarRemoteLocation),
-        new File(downloadLocation).toURI.toURL
-      )
+      val jar = URI.create(jarRemoteLocation)
+      if (HADOOP_FS_SCHEMES.contains(jar.getScheme)) {
+        val conf = kernel.sparkContext.hadoopConfiguration
+        val jarPath = new Path(jarRemoteLocation)
+        val fs = jarPath.getFileSystem(conf)
+        val destPath = if (downloadLocation.startsWith("file:")) {
+          new Path(downloadLocation)
+        } else {
+          new Path("file:" + downloadLocation)
+        }
+
+        fs.copyToLocalFile(
+          false /* keep original file */,
+          jarPath, destPath,
+          true /* don't create checksum files */)
+      } else {
+        downloadFile(
+          new URL(jarRemoteLocation),
+          new File(downloadLocation).toURI.toURL
+        )
+      }
 
       // Report download finished
       printStream.println(s"Finished download of $jarName")

kernel/src/test/scala/org/apache/toree/magic/builtin/AddJarSpec.scala

@@ -91,7 +91,8 @@ class AddJarSpec extends FunSpec with Matchers with MockitoSugar {
 
         url = """http://www.example.com/remotecontent?filepath=/path/to/someJar.jar"""
         jarName = addJarMagic.getFileFromLocation(url)
-        assert(jarName == "someJar.jar")
+        // File names come from the path, not from the query fragment
+        assert(jarName == "remotecontent")
 
         url = """http://www.example.com/"""
         jarName = addJarMagic.getFileFromLocation(url)