Add doc on running end to end tests

Signed-off-by: James Munnelly <james@munnelly.eu>

docs/devel/end-to-end-tests.rst

@@ -0,0 +1,60 @@
+========================
+Running end-to-end tests
+========================
+
+cert-manager has an end-to-end test suite that verifies functionality against a
+real Kubernetes cluster.
+
+This document explains how you can run the end-to-end tests yourself.
+This is useful when you have added or changed functionality in cert-manager and
+want to verify the software still works as expected.
+
+Requirements
+============
+
+Currently, a number of tools **must** be installed on your machine in order to
+run the tests:
+
+* ``docker`` - We provision a whole Kubernetes cluster within Docker, and so
+  an up to date version of Docker must be installed. The oldest Docker version
+  we have tested is 17.09.
+
+* kind_ - This
+  tool is responsible for actually building and starting the Kubernetes cluster
+  used during tests.
+
+* helm_ - A minimum version 2.10 is required.
+
+* ``kubectl`` - If you are running the tests on Linux, this step is
+  technically not required. For non-Linux hosts (i.e. OSX), you will need to
+  ensure you have a relatively new version of kubectl available on your PATH.
+
+* ``golang`` - We require golang to build cert-manager and various test
+  related components. You should use at least go version 1.9, although we
+  currently build with go 1.11 in our own CI.
+
+* An internet connection - tests require access to DNS, and optionally
+  Cloudflare APIs (if a Cloudflare API token is provided).
+
+Docker, helm and kubectl should be installed through your preferred means.
+
+``kind`` can be installed like so:
+
+.. code-block:: shell
+
+   go install k8s.io/test-infra/kind
+
+Run end-to-end tests
+====================
+
+You can run the end-to-end tests by executing the following:
+
+.. code-block:: shell
+
+   ./hack/ci/run-e2e-kind.sh
+
+The full suite may take up to 20 minutes to run.
+You can monitor output of this command to track progress.
+
+.. _kind: https://github.com/kubernetes/test-infra/tree/master/kind
+.. _helm: https://github.com/helm/helm

docs/devel/index.rst

@@ -5,5 +5,6 @@ Development documentation
    :maxdepth: 1
 
    develop-with-minikube
+   end-to-end-tests
    dns01-providers
    dco-sign-off