release: generate cloud-only images automatically

Previously, the cloudonly docker images were generated manually. This
operation requires entering the version and the cloudonly release
numbers. This step is error-prone and time consuming.

This PR adds a script that gets the version from the source tree and
guesses the cloudonly release number by enumerating through potential
release numbers and checking their existence.

This scrip can be run as part of the Build and Sign job, after we create
and push the staged docker images.

Fixes: RE-748
Release note: None

build/teamcity/internal/release/process/build-cockroach-release-cloud-only.sh

@@ -0,0 +1,92 @@
+#!/usr/bin/env bash
+
+# Copyright 2023 The Cockroach Authors.
+#
+# Use of this software is governed by the CockroachDB Software License
+# included in the /LICENSE file.
+
+
+set -euxo pipefail
+
+dir="$(dirname $(dirname $(dirname $(dirname $(dirname "${0}")))))"
+source "$dir/release/teamcity-support.sh"
+
+tc_start_block "Variable Setup"
+version=$(grep -v "^#" "$dir/../pkg/build/version.txt" | head -n1)
+if [[ -z "${DRY_RUN}" ]] ; then
+  gcr_staged_repository="us-docker.pkg.dev/releases-prod/cockroachdb-staged-releases/cockroach"
+  gcr_staged_credentials="$GCS_CREDENTIALS_PROD"
+  gcr_repository="us-docker.pkg.dev/cockroach-cloud-images/cockroachdb/cockroach"
+  gcr_credentials="$GOOGLE_COCKROACH_CLOUD_IMAGES_COCKROACHDB_CREDENTIALS"
+else
+  gcr_staged_repository="us-docker.pkg.dev/releases-dev-356314/cockroachdb-staged-releases/cockroach"
+  gcr_staged_credentials="$GCS_CREDENTIALS_DEV"
+  gcr_repository="us-docker.pkg.dev/releases-dev-356314/cockroachdb-staged-releases/cockroach-cloud-only"
+  gcr_credentials="$GCS_CREDENTIALS_DEV"
+fi
+tc_end_block "Variable Setup"
+
+
+docker_login_gcr "$gcr_staged_repository" "$gcr_staged_credentials"
+docker pull "${gcr_staged_repository}:amd64-${version}"
+docker pull "${gcr_staged_repository}:arm64-${version}"
+
+cloud_release=
+for i in $(seq 1 10); do
+  maybe_manifest="${gcr_repository}:$version-cloudonly.$i"
+  if ! docker manifest inspect "$maybe_manifest"; then
+    echo "$maybe_manifest not found, assuming this is what we need"
+    cloud_release="$i"
+    break
+  else
+    echo "$maybe_manifest already exist, trying next..."
+  fi
+done
+
+if [[ -z $cloud_release ]]; then
+  echo "cannot find available cloud_release, did we generate 10 of them?"
+  exit 1
+fi
+
+version_cloudonly="${version}-cloudonly.${cloud_release}"
+manifest="${gcr_repository}:${version_cloudonly}"
+
+docker_login_gcr "$gcr_repository" "$gcr_credentials"
+
+docker tag \
+  "${gcr_staged_repository}:amd64-${version}" \
+  "${gcr_repository}:amd64-${version_cloudonly}"
+docker tag \
+  "${gcr_staged_repository}:arm64-${version}" \
+  "${gcr_repository}:arm64-${version_cloudonly}"
+
+docker push "${gcr_repository}:amd64-${version_cloudonly}"
+docker push "${gcr_repository}:arm64-${version_cloudonly}"
+
+docker manifest rm "$manifest" || :
+docker manifest create \
+  "$manifest" \
+  "${gcr_repository}:amd64-${version_cloudonly}" \
+  "${gcr_repository}:arm64-${version_cloudonly}"
+
+docker manifest push "$manifest" 
+echo "==========="
+echo "published to"
+echo "$manifest"
+echo "==========="
+
+tc_start_block "Verify docker images"
+error=0
+for arch in amd64 arm64; do
+    tc_start_block "Verify $manifest on $arch"
+    if ! verify_docker_image "$manifest" "linux/$arch" "$BUILD_VCS_NUMBER" "$version" false; then
+      error=1
+    fi
+    tc_end_block "Verify $manifest on $arch"
+done
+
+if [ $error = 1 ]; then
+  echo "ERROR: Docker image verification failed, see logs above"
+  exit 1
+fi
+tc_end_block "Verify docker images"