Development workflow documentation for the current state of the world. (alteryx#20)

* Development workflow documentation for the current state of the world.

* Address comments.

* Clarified code change and added ticket link

Author: mccheah

resource-managers/kubernetes/README.md

@@ -0,0 +1,56 @@
+---
+layout: global
+title: Spark on Kubernetes Development
+---
+
+[Kubernetes](https://kubernetes.io/) is a framework for easily deploying, scaling, and managing containerized
+applications. It would be useful for a user to run their Spark jobs on a Kubernetes cluster alongside their
+other Kubernetes-managed applications. For more about the motivations for adding this feature, see the umbrella JIRA
+ticket that tracks this project: [SPARK-18278](https://issues.apache.org/jira/browse/SPARK-18278).
+
+This submodule is an initial implementation of allowing Kubernetes to be a
+supported cluster manager for Spark, along with Mesos, Hadoop YARN, and Standalone. This document provides a summary of
+important matters to keep in mind when developing this feature.
+
+# Building Spark with Kubernetes Support
+
+To build Spark with Kubernetes support, use the `kubernetes` profile when invoking Maven. For example, to simply compile
+the Kubernetes core implementation module along with its dependencies:
+
+    build/mvn compile -Pkubernetes -pl resource-managers/kubernetes/core -am
+
+To build a distribution of Spark with Kubernetes support, use the `dev/make-distribution.sh` script, and add the
+`kubernetes` profile as part of the build arguments. Any other build arguments can be specified as one would expect when
+building Spark normally. For example, to build Spark against Hadoop 2.7 and Kubernetes:
+
+    dev/make-distribution.sh --tgz -Phadoop2.7 -Pkubernetes
+
+# Kubernetes Code Modules
+
+Below is a list of the submodules for this cluster manager and what they do.
+
+* `core`: Implementation of the Kubernetes cluster manager support.
+* `integration-tests`: Integration tests for the project.
+* `docker-minimal-bundle`: Base Dockerfiles for the driver and the executors. The Dockerfiles are used for integration
+  tests as well as being provided in packaged distributions of Spark.
+* `integration-tests-spark-jobs`: Spark jobs that are only used in integration tests.
+* `integration-tests-spark-jobs-helpers`: Dependencies for the spark jobs used in integration tests. These dependencies
+  are separated out to facilitate testing the shipping of jars to drivers running on Kubernetes clusters.
+
+# Running the Kubernetes Integration Tests
+
+Note that the integration test framework is currently being heavily revised and is subject to change.
+
+Running any of the integration tests requires including `kubernetes-integration-tests` profile in the build command. In
+order to prepare the environment for running the integration tests, the `pre-integration-test` step must be run in Maven
+on the `resource-managers/kubernetes/integration-tests` module:
+
+  build/mvn pre-integration-test -Pkubernetes -Pkubernetes-integration-tests -pl resource-managers/kubernetes/integration-tests -am
+ 
+Afterwards, the integration tests can be executed with Maven or your IDE. Note that when running tests from an IDE, the
+`pre-integration-test` phase must be run every time the Spark main code changes. When running tests from the
+command line, the `pre-integration-test` phase should automatically be invoked if the `integration-test` phase is run.
+
+# Usage Guide
+
+See the [usage guide](../../docs/running-on-kubernetes.md) for more information.