Put Dockerfile into a temporary directory and fix tests

Author: koterpillar

hooks/lib/stdlib.bash

@@ -51,9 +51,7 @@ compute_tag() {
 
   echoerr 'DOCKERFILE'
   echoerr "+ ${docker_file}:${target:-"<target>"}"
-  # Inline Dockerfile might be saved under a different name each time,
-  # only content matters
-  sums="$(sha1sum < "${docker_file}")"
+  sums="$(cd ${docker_file_dir}; sha1sum $(basename ${docker_file}))"
   sums+="$(echo "${target}" | sha1sum)"
 
   echoerr 'ARCHITECTURE'

hooks/pre-command

@@ -13,18 +13,22 @@ if [ -n "${BUILDKITE_PLUGIN_DOCKER_ECR_CACHE_DOCKERFILE_INLINE:-}" ]
 then
   [ -n "${BUILDKITE_PLUGIN_DOCKER_ECR_CACHE_DOCKERFILE:-}" ] &&
     log_fatal "Cannot specify both 'dockerfile' and 'dockerfile-inline'."
-  docker_file="$(mktemp)"
+  # Put the Dockerfile into a temporary directory to work around
+  # https://github.com/docker/cli/issues/2249
+  docker_file_dir="$(mktemp -d)"
+  docker_file="${docker_file_dir}/Dockerfile"
   echo "$BUILDKITE_PLUGIN_DOCKER_ECR_CACHE_DOCKERFILE_INLINE" > "$docker_file"
-  docker_file_dir="."
+  context_dir="."
 else
   docker_file="${BUILDKITE_PLUGIN_DOCKER_ECR_CACHE_DOCKERFILE:-"Dockerfile"}"
-  docker_file_dir="$(dirname "${docker_file}")"
+  context_dir="$(dirname "${docker_file}")"
+  docker_file_dir="${context_dir}"
 fi
 target="${BUILDKITE_PLUGIN_DOCKER_ECR_CACHE_TARGET:-}"
 export_env_variable="${BUILDKITE_PLUGIN_DOCKER_ECR_CACHE_EXPORT_ENV_VARIABLE:-"BUILDKITE_PLUGIN_DOCKER_IMAGE"}"
 exec 3>&1
 tag="$(compute_tag "${docker_file}" 2>&3)"
-context="${BUILDKITE_PLUGIN_DOCKER_ECR_CACHE_CONTEXT:-"${docker_file_dir}"}"
+context="${BUILDKITE_PLUGIN_DOCKER_ECR_CACHE_CONTEXT:-"${context_dir}"}"
 
 build_args=()
 read_build_args

tests/pre-command.bats

@@ -73,14 +73,14 @@ pre_command_hook="$PWD/hooks/pre-command"
   export BUILDKITE_PLUGIN_DOCKER_ECR_CACHE_DOCKERFILE_INLINE="FROM stub"
   local repository_uri="pretend.host/path/segment/image"
 
-  one_time_mktemp=$(mktemp)
+  one_time_mktemp=$(mktemp -d)
 
   stub mktemp \
-    "echo $one_time_mktemp"
+    "-d : echo $one_time_mktemp"
 
   stub docker \
     "pull * : false" \
-    "build --file=$one_time_mktemp * : echo building docker image" \
+    "build --file=$one_time_mktemp/Dockerfile * : echo building docker image" \
     "tag ${repository_uri}:stubbed-computed-tag ${repository_uri}:latest : echo tagged latest" \
     "push ${repository_uri}:stubbed-computed-tag : echo pushed stubbed-computed-tag" \
     "push ${repository_uri}:latest : echo pushed latest"
@@ -92,7 +92,7 @@ pre_command_hook="$PWD/hooks/pre-command"
   assert_line "--- Pushing tag stubbed-computed-tag"
   assert_line "--- Pushing tag latest"
 
-  assert_equal "FROM stub" "$(cat $one_time_mktemp)"
+  assert_equal "FROM stub" "$(cat ${one_time_mktemp}/Dockerfile)"
 
   unstub mktemp
   unstub docker