[SPARK-22839][K8S] Remove the use of init-container for downloading remote dependencies

## What changes were proposed in this pull request?

Removal of the init-container for downloading remote dependencies. Built off of the work done by vanzin in an attempt to refactor driver/executor configuration elaborated in [this](https://issues.apache.org/jira/browse/SPARK-22839) ticket.

## How was this patch tested?

This patch was tested with unit and integration tests.

Author: Ilan Filonenko <[email protected]>

Closes apache#20669 from ifilonenko/remove-init-container.

Author: ifilonenko

bin/docker-image-tool.sh

@@ -63,9 +63,11 @@ function build {
     error "Cannot find docker image. This script must be run from a runnable distribution of Apache Spark."
   fi
 
+  local DOCKERFILE=${DOCKERFILE:-"$IMG_PATH/spark/Dockerfile"}
+
   docker build "${BUILD_ARGS[@]}" \
     -t $(image_ref spark) \
-    -f "$IMG_PATH/spark/Dockerfile" .
+    -f "$DOCKERFILE" .
 }
 
 function push {
@@ -83,6 +85,7 @@ Commands:
   push        Push a pre-built image to a registry. Requires a repository address to be provided.
 
 Options:
+  -f file     Dockerfile to build. By default builds the Dockerfile shipped with Spark.
   -r repo     Repository address.
   -t tag      Tag to apply to the built image, or to identify the image to be pushed.
   -m          Use minikube's Docker daemon.
@@ -112,10 +115,12 @@ fi
 
 REPO=
 TAG=
-while getopts mr:t: option
+DOCKERFILE=
+while getopts f:mr:t: option
 do
  case "${option}"
  in
+ f) DOCKERFILE=${OPTARG};;
  r) REPO=${OPTARG};;
  t) TAG=${OPTARG};;
  m)

core/src/main/scala/org/apache/spark/deploy/SparkSubmit.scala

@@ -320,8 +320,6 @@ object SparkSubmit extends CommandLineUtils with Logging {
         printErrorAndExit("Python applications are currently not supported for Kubernetes.")
       case (KUBERNETES, _) if args.isR =>
         printErrorAndExit("R applications are currently not supported for Kubernetes.")
-      case (KUBERNETES, CLIENT) =>
-        printErrorAndExit("Client mode is currently not supported for Kubernetes.")
       case (LOCAL, CLUSTER) =>
         printErrorAndExit("Cluster deploy mode is not compatible with master \"local\"")
       case (_, CLUSTER) if isShell(args.primaryResource) =>

docs/running-on-kubernetes.md

@@ -126,29 +126,6 @@ Those dependencies can be added to the classpath by referencing them with `local
 dependencies in custom-built Docker images in `spark-submit`. Note that using application dependencies from the submission
 client's local file system is currently not yet supported.
 
-
-### Using Remote Dependencies
-When there are application dependencies hosted in remote locations like HDFS or HTTP servers, the driver and executor pods
-need a Kubernetes [init-container](https://kubernetes.io/docs/concepts/workloads/pods/init-containers/) for downloading
-the dependencies so the driver and executor containers can use them locally.
-
-The init-container handles remote dependencies specified in `spark.jars` (or the `--jars` option of `spark-submit`) and
-`spark.files` (or the `--files` option of `spark-submit`). It also handles remotely hosted main application resources, e.g.,
-the main application jar. The following shows an example of using remote dependencies with the `spark-submit` command:
-
-```bash
-$ bin/spark-submit \
-    --master k8s://https://<k8s-apiserver-host>:<k8s-apiserver-port> \
-    --deploy-mode cluster \
-    --name spark-pi \
-    --class org.apache.spark.examples.SparkPi \
-    --jars https://path/to/dependency1.jar,https://path/to/dependency2.jar
-    --files hdfs://host:port/path/to/file1,hdfs://host:port/path/to/file2
-    --conf spark.executor.instances=5 \
-    --conf spark.kubernetes.container.image=<spark-image> \
-    https://path/to/examples.jar
-```
-
 ## Secret Management
 Kubernetes [Secrets](https://kubernetes.io/docs/concepts/configuration/secret/) can be used to provide credentials for a
 Spark application to access secured services. To mount a user-specified secret into the driver container, users can use
@@ -163,10 +140,6 @@ namespace as that of the driver and executor pods. For example, to mount a secre
 --conf spark.kubernetes.executor.secrets.spark-secret=/etc/secrets
 ```
 
-Note that if an init-container is used, any secret mounted into the driver container will also be mounted into the
-init-container of the driver. Similarly, any secret mounted into an executor container will also be mounted into the
-init-container of the executor.
-
 ## Introspection and Debugging
 
 These are the different ways in which you can investigate a running/completed Spark application, monitor progress, and
@@ -604,60 +577,20 @@ specific to Spark on Kubernetes.
     the Driver process. The user can specify multiple of these to set multiple environment variables.
   </td>
 </tr>
-<tr>
-  <td><code>spark.kubernetes.mountDependencies.jarsDownloadDir</code></td>
-  <td><code>/var/spark-data/spark-jars</code></td>
-  <td>
-    Location to download jars to in the driver and executors.
-    This directory must be empty and will be mounted as an empty directory volume on the driver and executor pods.
-  </td>
-</tr>
-<tr>
-  <td><code>spark.kubernetes.mountDependencies.filesDownloadDir</code></td>
-  <td><code>/var/spark-data/spark-files</code></td>
-  <td>
-    Location to download jars to in the driver and executors.
-    This directory must be empty and will be mounted as an empty directory volume on the driver and executor pods.
-  </td>
-</tr>
-<tr>
-  <td><code>spark.kubernetes.mountDependencies.timeout</code></td>
-  <td>300s</td>
-  <td>
-   Timeout in seconds before aborting the attempt to download and unpack dependencies from remote locations into
-   the driver and executor pods.
-  </td>
-</tr>
-<tr>
-  <td><code>spark.kubernetes.mountDependencies.maxSimultaneousDownloads</code></td>
-  <td>5</td>
-  <td>
-   Maximum number of remote dependencies to download simultaneously in a driver or executor pod.
-  </td>
-</tr>
-<tr>
-  <td><code>spark.kubernetes.initContainer.image</code></td>
-  <td><code>(value of spark.kubernetes.container.image)</code></td>
-  <td>
-   Custom container image for the init container of both driver and executors.
-  </td>
-</tr>
 <tr>
   <td><code>spark.kubernetes.driver.secrets.[SecretName]</code></td>
   <td>(none)</td>
   <td>
    Add the <a href="https://kubernetes.io/docs/concepts/configuration/secret/">Kubernetes Secret</a> named <code>SecretName</code> to the driver pod on the path specified in the value. For example,
-   <code>spark.kubernetes.driver.secrets.spark-secret=/etc/secrets</code>. Note that if an init-container is used,
-   the secret will also be added to the init-container in the driver pod.
+   <code>spark.kubernetes.driver.secrets.spark-secret=/etc/secrets</code>.
   </td>
 </tr>
 <tr>
   <td><code>spark.kubernetes.executor.secrets.[SecretName]</code></td>
   <td>(none)</td>
   <td>
    Add the <a href="https://kubernetes.io/docs/concepts/configuration/secret/">Kubernetes Secret</a> named <code>SecretName</code> to the executor pod on the path specified in the value. For example,
-   <code>spark.kubernetes.executor.secrets.spark-secret=/etc/secrets</code>. Note that if an init-container is used,
-   the secret will also be added to the init-container in the executor pod.
+   <code>spark.kubernetes.executor.secrets.spark-secret=/etc/secrets</code>.
   </td>
 </tr>
 </table>

examples/src/main/scala/org/apache/spark/examples/SparkRemoteFileTest.scala

@@ -0,0 +1,48 @@
+/*
+ * 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.
+ */
+
+// scalastyle:off println
+package org.apache.spark.examples
+
+import java.io.File
+
+import org.apache.spark.SparkFiles
+import org.apache.spark.sql.SparkSession
+
+/** Usage: SparkRemoteFileTest [file] */
+object SparkRemoteFileTest {
+  def main(args: Array[String]) {
+    if (args.length < 1) {
+      System.err.println("Usage: SparkRemoteFileTest <file>")
+      System.exit(1)
+    }
+    val spark = SparkSession
+      .builder()
+      .appName("SparkRemoteFileTest")
+      .getOrCreate()
+    val sc = spark.sparkContext
+    val rdd = sc.parallelize(Seq(1)).map(_ => {
+      val localLocation = SparkFiles.get(args(0))
+      println(s"${args(0)} is stored at: $localLocation")
+      new File(localLocation).isFile
+    })
+    val truthCheck = rdd.collect().head
+    println(s"Mounting of ${args(0)} was $truthCheck")
+    spark.stop()
+  }
+}
+// scalastyle:on println

resource-managers/kubernetes/core/src/main/scala/org/apache/spark/deploy/k8s/Config.scala

@@ -79,6 +79,12 @@ private[spark] object Config extends Logging {
       .stringConf
       .createOptional
 
+  val KUBERNETES_DRIVER_SUBMIT_CHECK =
+    ConfigBuilder("spark.kubernetes.submitInDriver")
+    .internal()
+    .booleanConf
+    .createOptional
+
   val KUBERNETES_EXECUTOR_LIMIT_CORES =
     ConfigBuilder("spark.kubernetes.executor.limit.cores")
       .doc("Specify the hard cpu limit for each executor pod")
@@ -135,73 +141,6 @@ private[spark] object Config extends Logging {
       .checkValue(interval => interval > 0, s"Logging interval must be a positive time value.")
       .createWithDefaultString("1s")
 
-  val JARS_DOWNLOAD_LOCATION =
-    ConfigBuilder("spark.kubernetes.mountDependencies.jarsDownloadDir")
-      .doc("Location to download jars to in the driver and executors. When using " +
-        "spark-submit, this directory must be empty and will be mounted as an empty directory " +
-        "volume on the driver and executor pod.")
-      .stringConf
-      .createWithDefault("/var/spark-data/spark-jars")
-
-  val FILES_DOWNLOAD_LOCATION =
-    ConfigBuilder("spark.kubernetes.mountDependencies.filesDownloadDir")
-      .doc("Location to download files to in the driver and executors. When using " +
-        "spark-submit, this directory must be empty and will be mounted as an empty directory " +
-        "volume on the driver and executor pods.")
-      .stringConf
-      .createWithDefault("/var/spark-data/spark-files")
-
-  val INIT_CONTAINER_IMAGE =
-    ConfigBuilder("spark.kubernetes.initContainer.image")
-      .doc("Image for the driver and executor's init-container for downloading dependencies.")
-      .fallbackConf(CONTAINER_IMAGE)
-
-  val INIT_CONTAINER_MOUNT_TIMEOUT =
-    ConfigBuilder("spark.kubernetes.mountDependencies.timeout")
-      .doc("Timeout before aborting the attempt to download and unpack dependencies from remote " +
-        "locations into the driver and executor pods.")
-      .timeConf(TimeUnit.SECONDS)
-      .createWithDefault(300)
-
-  val INIT_CONTAINER_MAX_THREAD_POOL_SIZE =
-    ConfigBuilder("spark.kubernetes.mountDependencies.maxSimultaneousDownloads")
-      .doc("Maximum number of remote dependencies to download simultaneously in a driver or " +
-        "executor pod.")
-      .intConf
-      .createWithDefault(5)
-
-  val INIT_CONTAINER_REMOTE_JARS =
-    ConfigBuilder("spark.kubernetes.initContainer.remoteJars")
-      .doc("Comma-separated list of jar URIs to download in the init-container. This is " +
-        "calculated from spark.jars.")
-      .internal()
-      .stringConf
-      .createOptional
-
-  val INIT_CONTAINER_REMOTE_FILES =
-    ConfigBuilder("spark.kubernetes.initContainer.remoteFiles")
-      .doc("Comma-separated list of file URIs to download in the init-container. This is " +
-        "calculated from spark.files.")
-      .internal()
-      .stringConf
-      .createOptional
-
-  val INIT_CONTAINER_CONFIG_MAP_NAME =
-    ConfigBuilder("spark.kubernetes.initContainer.configMapName")
-      .doc("Name of the config map to use in the init-container that retrieves submitted files " +
-        "for the executor.")
-      .internal()
-      .stringConf
-      .createOptional
-
-  val INIT_CONTAINER_CONFIG_MAP_KEY_CONF =
-    ConfigBuilder("spark.kubernetes.initContainer.configMapKey")
-      .doc("Key for the entry in the init container config map for submitted files that " +
-        "corresponds to the properties for this init-container.")
-      .internal()
-      .stringConf
-      .createOptional
-
   val KUBERNETES_AUTH_SUBMISSION_CONF_PREFIX =
     "spark.kubernetes.authenticate.submission"
 

resource-managers/kubernetes/core/src/main/scala/org/apache/spark/deploy/k8s/Constants.scala

@@ -63,22 +63,13 @@ private[spark] object Constants {
   val ENV_MOUNTED_CLASSPATH = "SPARK_MOUNTED_CLASSPATH"
   val ENV_JAVA_OPT_PREFIX = "SPARK_JAVA_OPT_"
   val ENV_CLASSPATH = "SPARK_CLASSPATH"
-  val ENV_DRIVER_MAIN_CLASS = "SPARK_DRIVER_CLASS"
-  val ENV_DRIVER_ARGS = "SPARK_DRIVER_ARGS"
-  val ENV_DRIVER_JAVA_OPTS = "SPARK_DRIVER_JAVA_OPTS"
   val ENV_DRIVER_BIND_ADDRESS = "SPARK_DRIVER_BIND_ADDRESS"
-  val ENV_DRIVER_MEMORY = "SPARK_DRIVER_MEMORY"
-  val ENV_MOUNTED_FILES_DIR = "SPARK_MOUNTED_FILES_DIR"
-
-  // Bootstrapping dependencies with the init-container
-  val INIT_CONTAINER_DOWNLOAD_JARS_VOLUME_NAME = "download-jars-volume"
-  val INIT_CONTAINER_DOWNLOAD_FILES_VOLUME_NAME = "download-files-volume"
-  val INIT_CONTAINER_PROPERTIES_FILE_VOLUME = "spark-init-properties"
-  val INIT_CONTAINER_PROPERTIES_FILE_DIR = "/etc/spark-init"
-  val INIT_CONTAINER_PROPERTIES_FILE_NAME = "spark-init.properties"
-  val INIT_CONTAINER_PROPERTIES_FILE_PATH =
-    s"$INIT_CONTAINER_PROPERTIES_FILE_DIR/$INIT_CONTAINER_PROPERTIES_FILE_NAME"
-  val INIT_CONTAINER_SECRET_VOLUME_NAME = "spark-init-secret"
+  val ENV_SPARK_CONF_DIR = "SPARK_CONF_DIR"
+  // Spark app configs for containers
+  val SPARK_CONF_VOLUME = "spark-conf-volume"
+  val SPARK_CONF_DIR_INTERNAL = "/opt/spark/conf"
+  val SPARK_CONF_FILE_NAME = "spark.properties"
+  val SPARK_CONF_PATH = s"$SPARK_CONF_DIR_INTERNAL/$SPARK_CONF_FILE_NAME"
 
   // Miscellaneous
   val KUBERNETES_MASTER_INTERNAL_URL = "https://kubernetes.default.svc"