.prow.sh: enable Prow testing

With some tweaking it is possible to use most of the E2E testing
scripts from csi-release-tools.

Sanity testing is not enabled.

.prow.sh

@@ -0,0 +1,37 @@
+#! /bin/bash
+
+# Only these tests work for csi-drivers-flex, E2E and sanity testing
+# will require further work.
+: ${CSI_PROW_TESTS:="unit serial parallel serial-alpha parallel-alpha"}
+
+# Customize deployment and E2E testing.
+: ${CSI_PROW_DEPLOY_SCRIPT:="deploy.sh"}
+: ${CSI_PROW_DEPLOYMENT:="kubernetes"}
+: ${CSI_PROW_E2E_TEST_PREFIX:="CSI Volumes"}
+
+. release-tools/prow.sh
+
+# Install custom E2E test suite as bin/tests.
+install_e2e () {
+    if [ -e "${CSI_PROW_WORK}/e2e.test" ]; then
+        return
+    fi
+
+    make build-tests && cp bin/tests "${CSI_PROW_WORK}/e2e.test"
+}
+
+# Invoke the custom E2E test suite for a certain subset of the tests (serial, parallel, ...)
+run_e2e () (
+    name="$1"
+    shift
+
+    install_e2e || die "building e2e.test failed"
+    install_ginkgo || die "installing ginkgo failed"
+
+    trap "move_junit '$name'" EXIT
+
+    cd "${GOPATH}/src/${CSI_PROW_E2E_IMPORT_PATH}" &&
+    run_with_loggers ginkgo -v "$@" "${CSI_PROW_WORK}/e2e.test" -- -report-dir "${ARTIFACTS}"
+)
+
+main