Mount google-cloud-sdk into e2e image

hack/run-e2e.sh

@@ -28,6 +28,7 @@ GCP_PROJECT=${GCP_PROJECT:-}
 GCP_REGION=${GCP_REGION:-}
 GCP_ZONE=${GCP_ZONE:-}
 GCP_CREDENTIALS=${GCP_CREDENTIALS:-}
+GCP_SDK=${GCP_SDK:-/google-cloud-sdk}
 IMAGE_TAG=${IMAGE_TAG:-}
 SKIP_IMAGE_LOAD=${SKIP_IMAGE_LOAD:-}
 TIDB_OPERATOR_IMAGE=${TIDB_OPERATOR_IMAGE:-localhost:5000/pingcap/tidb-operator:latest}
@@ -370,6 +371,15 @@ elif [ "$PROVIDER" == "gke" ]; then
         -v ${GCP_CREDENTIALS}:${GCP_CREDENTIALS}
         --env GOOGLE_APPLICATION_CREDENTIALS=${GCP_CREDENTIALS}
     )
+    # google-cloud-sdk is very large, we didn't pack it into our e2e image.
+    # instead, we use the sdk installed in CI image.
+    if [ ! -e "${GCP_SDK}/bin/gcloud" ]; then
+        echo "error: ${GCP_SDK} is not google cloud sdk, please install it here or specify correct path via GCP_SDK env"
+        exit 1
+    fi
+    docker_args+=(
+        -v ${GCP_SDK}:/google-cloud-sdk
+    )
 else
     e2e_args+=(
         --provider=${PROVIDER}

tests/images/e2e/Dockerfile

@@ -28,3 +28,6 @@ ADD bin/e2e.test /usr/local/bin/
 ADD bin/webhook /usr/local/bin/
 ADD bin/blockwriter /usr/local/bin/
 ADD bin/apiserver /usr/local/bin/
+
+ADD entrypoint.sh /usr/local/bin
+ENTRYPOINT ["/usr/local/bin/entrypoint.sh"]

tests/images/e2e/entrypoint.sh

@@ -0,0 +1,17 @@
+#!/bin/bash
+
+set -e
+
+# Add default command if no command provided or the first argument is an
+# option.
+if [ $# -lt 1 -o "${1:0:1}" = '-' ]; then
+    set -- /usr/local/bin/ginkgo "$@"
+fi
+
+# If google-cloud-sdk is detected, install it.
+if [ -d /google-cloud-sdk ]; then
+    source /google-cloud-sdk/path.bash.inc
+    export CLOUDSDK_CORE_DISABLE_PROMPTS=1
+fi
+
+exec "$@"