Merge pull request #1259 from buildkite/pdp-1893-make-sure-tag-builds-have-the-latest-tags

Author: triarius

.buildkite/pipeline.yaml

@@ -188,8 +188,6 @@ steps:
     command: .buildkite/steps/publish.sh
     agents:
       queue: "${BUILDKITE_AGENT_META_DATA_QUEUE}"
-    env:
-      BUILDKITE_GIT_FETCH_FLAGS: -v --prune --tags
     concurrency_group: "aws-stack-publish"
     concurrency: 1
     concurrency_method: eager

.buildkite/steps/publish.sh

@@ -8,7 +8,22 @@ s3_upload_templates() {
   aws s3 cp --content-type 'text/yaml' --acl public-read build/aws-stack.yml "s3://${BUILDKITE_AWS_STACK_TEMPLATE_BUCKET}/${bucket_prefix}aws-stack.yml"
 }
 
+echo "--- :git: Checking and fetching git tags"
+# if BUILDKITE_TAG is set, fetch the tags, and check that it's a valid tag
+if [[ -n "${BUILDKITE_TAG:-}" ]]; then
+  git fetch -v --tags
+  if ! git tag --list | grep -q "^${BUILDKITE_TAG}$"; then
+    echo "^^^ +++"
+    echo "Tag ${BUILDKITE_TAG} does not exist"
+    exit 1
+  fi
+else
+  echo "Not a tag build, skipping tag check"
+fi
+
+echo "--- :aws: Checking template bucket is set"
 if [[ -z "${BUILDKITE_AWS_STACK_TEMPLATE_BUCKET}" ]]; then
+  echo "^^^ +++"
   echo "Must set an s3 bucket in BUILDKITE_AWS_STACK_TEMPLATE_BUCKET for publishing templates to"
   exit 1
 fi
@@ -17,9 +32,6 @@ echo "--- Downloading mappings.yml artifact"
 mkdir -p build/
 buildkite-agent artifact download build/mappings.yml build/
 
-echo "--- Fetching latest git tags"
-git fetch --tags
-
 echo "--- Building :cloudformation: CloudFormation templates"
 make build/aws-stack.yml