Run the end-to-end tests in presubmit (knative#106)

The end-to-end tests are run only if the build and unit tests pass.

Bonus:
* assorted minor cleanups in the script
* partially addresses issue knative/serving#503
* updates to e2e-tests.sh:
  - reset to the default namespace after creating the cluster
  - create test cluster in us-central-1a, as us-east-1d is reaching its resource limit
  - dump info about the project used, for test diagnostic purposes

tests/e2e-tests.sh

@@ -30,7 +30,7 @@
 
 # Test cluster parameters and location of generated test images
 readonly E2E_CLUSTER_NAME=ela-e2e-cluster
-readonly E2E_CLUSTER_ZONE=us-east1-d
+readonly E2E_CLUSTER_ZONE=us-central1-a
 readonly E2E_CLUSTER_NODES=2
 readonly E2E_CLUSTER_MACHINE=n1-standard-2
 readonly GKE_VERSION=v1.9.4-gke.1
@@ -160,6 +160,8 @@ if [[ -z ${K8S_CLUSTER_OVERRIDE} ]]; then
   kubectl --username=admin --password=$passwd create clusterrolebinding cluster-admin-binding \
       --clusterrole=cluster-admin \
       --user=${K8S_USER_OVERRIDE}
+  # Make sure we're in the default namespace
+  kubectl config set-context $K8S_CLUSTER_OVERRIDE --namespace=default
 fi
 readonly USING_EXISTING_CLUSTER
 
@@ -172,6 +174,8 @@ fi
 echo "================================================="
 echo "* Cluster is ${K8S_CLUSTER_OVERRIDE}"
 echo "* Docker is ${DOCKER_REPO_OVERRIDE}"
+echo "*** Project info ***"
+gcloud compute project-info describe
 
 header "Building and starting the controller"
 trap teardown EXIT

tests/presubmit-tests.sh

@@ -21,14 +21,21 @@
 set -o errexit
 set -o pipefail
 
-SCRIPT_ROOT=$(dirname ${BASH_SOURCE})/..
-OG_DOCKER_REPO="${DOCKER_REPO_OVERRIDE}"
+# Useful environment variables
+readonly BUILDCRD_ROOT=$(dirname ${BASH_SOURCE})/..
+[[ $USER == "prow" ]] && IS_PROW=1 || IS_PROW=0
+readonly IS_PROW
 
-set -o nounset
+# Save *_OVERRIDE variables in case a cleanup is required.
+readonly OG_DOCKER_REPO="${DOCKER_REPO_OVERRIDE}"
+
+function restore_env() {
+  export DOCKER_REPO_OVERRIDE="${OG_DOCKER_REPO}"
+}
 
 function cleanup() {
   header "Cleanup (teardown)"
-  export DOCKER_REPO_OVERRIDE="${OG_DOCKER_REPO}"
+  restore_env
   # --expunge is a workaround for https://github.com/elafros/elafros/issues/366
   bazel clean --expunge || true
 }
@@ -39,13 +46,13 @@ function header() {
   echo "================================================="
 }
 
-cd ${SCRIPT_ROOT}
+cd ${BUILDCRD_ROOT}
 
 # Set the required env vars to dummy values to satisfy bazel.
 export DOCKER_REPO_OVERRIDE=REPO_NOT_SET
 
 # For local runs, cleanup before and after the tests.
-if [[ ! $USER == "prow" ]]; then
+if (( ! IS_PROW )); then
   trap cleanup EXIT
   header "Cleanup (setup)"
   # --expunge is a workaround for https://github.com/elafros/elafros/issues/366
@@ -58,7 +65,11 @@ fi
 header "Building phase"
 bazel build //cmd/... //pkg/...
 
-# Step 2: Run tests.
+# Step 2: Run unit tests.
 header "Testing phase"
 bazel test //cmd/... //pkg/...
 
+# Step 3: Run end-to-end tests.
+# Restore environment variables, let e2e-tests.sh handle them.
+restore_env
+./tests/e2e-tests.sh