Merge pull request #160 from buildkite-plugins/fix-cache-from-for-ser…

…vice-names-with-dashes

Fix cache-from errors with service containing hyphens

commands/build.sh

@@ -6,14 +6,19 @@ pull_retries="$(plugin_read_config PULL_RETRIES "0")"
 override_file="docker-compose.buildkite-${BUILDKITE_BUILD_NUMBER}-override.yml"
 build_images=()
 
+service_name_cache_from_var() {
+  local service_name="$1"
+  echo "cache_from__${service_name//-/_}"
+}
+
 for line in $(plugin_read_list CACHE_FROM) ; do
   IFS=':' read -r -a tokens <<< "$line"
   service_name=${tokens[0]}
   service_image=$(IFS=':'; echo "${tokens[*]:1}")
 
   echo "~~~ :docker: Pulling cache image for $service_name"
   if retry "$pull_retries" plugin_prompt_and_run docker pull "$service_image" ; then
-    printf -v "cache_from__${service_name}" %s "$service_image"
+    printf -v "$(service_name_cache_from_var "$service_name")" "%s" "$service_image"
   else
     echo "!!! :docker: Pull failed. $service_image will not be used as a cache for $service_name"
   fi
@@ -31,9 +36,9 @@ for service_name in $(plugin_read_list BUILD) ; do
 
   build_images+=("$service_name" "$image_name")
 
-  cache_key="cache_from__${service_name}"
-  if [[ -n "${!cache_key-}" ]]; then
-    build_images+=("${!cache_key}")
+  cache_from_var="$(service_name_cache_from_var "${service_name}")"
+  if [[ -n "${!cache_from_var-}" ]]; then
+    build_images+=("${!cache_from_var}")
   else
     build_images+=("")
   fi

tests/build.bats

@@ -221,6 +221,30 @@ load '../lib/shared'
   unstub docker-compose
 }
 
+@test "Build with a cache-from image with hyphen" {
+  export BUILDKITE_PLUGIN_DOCKER_COMPOSE_CONFIG="tests/composefiles/docker-compose.v3.2.yml"
+  export BUILDKITE_JOB_ID=1111
+  export BUILDKITE_PLUGIN_DOCKER_COMPOSE_BUILD_0=hello-world
+  export BUILDKITE_PLUGIN_DOCKER_COMPOSE_CACHE_FROM_0=hello-world:my.repository/my-service_cache:latest
+  export BUILDKITE_PIPELINE_SLUG=test
+  export BUILDKITE_BUILD_NUMBER=1
+
+  stub docker \
+    "pull my.repository/my-service_cache:latest : echo pulled cache image"
+
+  stub docker-compose \
+    "-f tests/composefiles/docker-compose.v3.2.yml -p buildkite1111 -f docker-compose.buildkite-1-override.yml build --pull hello-world : echo built hello-world"
+
+  run $PWD/hooks/command
+
+  assert_success
+  assert_output --partial "pulled cache image"
+  assert_output --partial "- my.repository/my-service_cache:latest"
+  assert_output --partial "built hello-world"
+  unstub docker
+  unstub docker-compose
+}
+
 @test "Build with a cache-from image retry on failing pull" {
   export BUILDKITE_PLUGIN_DOCKER_COMPOSE_CONFIG="tests/composefiles/docker-compose.v3.2.yml"
   export BUILDKITE_JOB_ID=1111