chore: Using trampoline strategy for releases (#1541)

* chore: Using trampoline strategy for releases

* chore: reinstating test command

.kokoro/common.cfg

@@ -1,5 +1,17 @@
 # Format: //devtools/kokoro/config/proto/build.proto
 
+# Download trampoline resources.
+gfile_resources: "/bigstore/cloud-devrel-kokoro-resources/trampoline"
+
+# Use the trampoline script to run in docker.
+build_file: "spring-cloud-gcp/.kokoro/trampoline.sh"
+
+# Configure the docker image for kokoro-trampoline.
+env_vars: {
+  key: "TRAMPOLINE_IMAGE"
+  value: "gcr.io/cloud-devrel-kokoro-resources/java17"
+}
+
 before_action {
   fetch_keystore {
     keystore_resource {

.kokoro/populate-secrets.sh

@@ -0,0 +1,43 @@
+#!/bin/bash
+# Copyright 2020 Google LLC.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+set -eo pipefail
+
+function now { date +"%Y-%m-%d %H:%M:%S" | tr -d '\n' ;}
+function msg { println "$*" >&2 ;}
+function println { printf '%s\n' "$(now) $*" ;}
+
+
+# Populates requested secrets set in SECRET_MANAGER_KEYS from service account:
+# kokoro-trampoline@cloud-devrel-kokoro-resources.iam.gserviceaccount.com
+SECRET_LOCATION="${KOKORO_GFILE_DIR}/secret_manager"
+msg "Creating folder on disk for secrets: ${SECRET_LOCATION}"
+mkdir -p ${SECRET_LOCATION}
+for key in $(echo ${SECRET_MANAGER_KEYS} | sed "s/,/ /g")
+do
+  msg "Retrieving secret ${key}"
+  docker run --entrypoint=gcloud \
+    --volume=${KOKORO_GFILE_DIR}:${KOKORO_GFILE_DIR} \
+    gcr.io/google.com/cloudsdktool/cloud-sdk \
+    secrets versions access latest \
+    --project cloud-devrel-kokoro-resources \
+    --secret ${key} > \
+    "${SECRET_LOCATION}/${key}"
+  if [[ $? == 0 ]]; then
+    msg "Secret written to ${SECRET_LOCATION}/${key}"
+  else
+    msg "Error retrieving secret ${key}"
+  fi
+done

.kokoro/stage.cfg

@@ -1,3 +1,18 @@
 # Format: //devtools/kokoro/config/proto/build.proto
 
-build_file: "spring-cloud-gcp/.kokoro/stage.sh"
+env_vars: {
+  key: "TRAMPOLINE_BUILD_FILE"
+  value: "github/spring-cloud-gcp/.kokoro/stage.sh"
+}
+
+action {
+  define_artifacts {
+    regex: "github/spring-cloud-gcp/target/nexus-staging/staging/*.properties"
+    strip_prefix: "github/spring-cloud-gcp"
+  }
+}
+
+env_vars: {
+  key: "SECRET_MANAGER_KEYS"
+  value: "releasetool-publish-reporter-app,releasetool-publish-reporter-googleapis-installation,releasetool-publish-reporter-pem"
+}

.kokoro/stage.sh

@@ -29,16 +29,10 @@ setup_environment_secrets
 create_settings_xml_file $MAVEN_SETTINGS_FILE
 
 # run unit tests
-./mvnw verify --show-version --batch-mode
-
-# change to release version
-./mvnw versions:set --batch-mode -DremoveSnapshot -DprocessAllModules
-
-# build and install the jars locally
-./mvnw clean install --batch-mode -DskipTests=true
+  mvn verify --show-version --batch-mode
 
 # stage release
-./mvnw deploy \
+  mvn deploy \
   --batch-mode \
   --settings ${MAVEN_SETTINGS_FILE} \
   -DskipTests=true \
@@ -51,7 +45,7 @@ create_settings_xml_file $MAVEN_SETTINGS_FILE
 # promote release
 if [[ -n "${AUTORELEASE_PR}" ]]
 then
-  ./mvnw nexus-staging:release \
+    mvn nexus-staging:release \
     --batch-mode \
     --settings ${MAVEN_SETTINGS_FILE} \
     -Drelease=true \

.kokoro/trampoline.sh

@@ -0,0 +1,26 @@
+#!/bin/bash
+# Copyright 2018 Google Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+set -eo pipefail
+# Always run the cleanup script, regardless of the success of bouncing into
+# the container.
+function cleanup() {
+    chmod +x ${KOKORO_GFILE_DIR}/trampoline_cleanup.sh
+    ${KOKORO_GFILE_DIR}/trampoline_cleanup.sh
+    echo "cleanup";
+}
+trap cleanup EXIT
+
+$(dirname $0)/populate-secrets.sh # Secret Manager secrets.
+python3 "${KOKORO_GFILE_DIR}/trampoline_v1.py"