Add a job to download the data to PVC. (#97)

* This is the first step to doing training and serving using a PV as opposed
  to GCS.

* This will make the sample easier to run anyhere and in particular on Katacoda.

* This currently would work as follows

User creates a PVC

ks apply ${ENV} -c data-pvc

User runs a K8s job to download the data to PVC

ks apply ${ENV} -c data-downloader

In subsequent PRs we will update the train and serve steps to load the
model from the PVC as opposed to GCS.

Related to #91

github_issue_summarization/ks-kubeflow/components/data-downloader.jsonnet

@@ -0,0 +1,74 @@
+// Run a job to download the data to a persistent volume.
+//
+local env = std.extVar("__ksonnet/environments");
+local params = std.extVar("__ksonnet/params").components["data-pvc"];
+local k = import "k.libsonnet";
+
+
+local script = importstr "download_data.sh";
+
+local scriptConfigMap = {
+  apiVersion: "v1",
+  kind: "ConfigMap",
+  metadata: {
+    name: "downloader",
+    namespace: env.namespace,
+  },
+
+  data: {
+    "download_data.sh": script,
+  },
+};
+
+local downLoader = {
+  apiVersion: "batch/v1",
+  kind: "Job",
+  metadata: {
+    name: "download-data",
+    namespace: env.namespace,
+  },
+  spec: {
+    backoffLimit: 4,
+    template: {
+      spec: {
+        containers: [
+          {
+            command: [
+              "/bin/ash",
+              "/scripts/download_data.sh",
+            ],
+            image: "busybox",
+            name: "downloader",
+            volumeMounts: [
+              {
+                name: "script",
+                mountPath: "/scripts",
+              },
+              {
+                name: "data",
+                mountPath: "/data",
+              },
+            ],
+          },
+        ],
+        restartPolicy: "Never",
+        volumes: [
+          {
+            name: "script",
+            configMap: {
+              name: "downloader",
+            },
+          },
+          {
+            name: "data",
+            persistentVolumeClaim: {
+              claimName: "data-pvc",
+            },
+          },
+        ],
+      },
+    },
+  },
+};
+
+std.prune(k.core.v1.list.new([downLoader, scriptConfigMap]))

github_issue_summarization/ks-kubeflow/components/data-pvc.jsonnet

@@ -0,0 +1,28 @@
+// Create a PVC to store the data.
+// This PVC can be used if you don't have access to an object store
+// but your cluster has a default storage class
+local env = std.extVar("__ksonnet/environments");
+local params = std.extVar("__ksonnet/params").components["data-pvc"];
+local k = import "k.libsonnet";
+
+
+local pvc = {
+  apiVersion: "v1",
+  kind: "PersistentVolumeClaim",
+  metadata: {
+    name: "data-pvc",
+    namespace: env.namespace,
+  },
+  spec: {
+    accessModes: [
+      "ReadWriteOnce",
+    ],
+    resources: {
+      requests: {
+        storage: "10Gi",
+      },
+    },
+  },
+};
+
+std.prune(k.core.v1.list.new([pvc]))

github_issue_summarization/ks-kubeflow/components/download_data.sh

@@ -0,0 +1,13 @@
+#!/bin/bash
+#
+# Script to download the data
+set -ex
+
+DATA_DIR=/data
+
+mkdir -p ${DATA_DIR}
+
+wget --directory-prefix=${DATA_DIR} \
+	https://storage.googleapis.com/kubeflow-examples/github-issue-summarization-data/github-issues.zip
+
+unzip -d ${DATA_DIR} ${DATA_DIR}/github-issues.zip

github_issue_summarization/ks-kubeflow/components/params.libsonnet

@@ -6,6 +6,9 @@
   components: {
     // Component-level parameters, defined initially from 'ks prototype use ...'
     // Each object below should correspond to a component in the components/ directory
+    "data-pvc": {
+    },
+
     "kubeflow-core": {
       cloud: "null",
       disks: "null",