refactor: make entrypoint script more posix compliant

remove most of the 'bashisms' in the script, improve quoting, escaping and make more consistent regarding references to variable names
aevea · Jan 20, 2024 · 612a1fd · 612a1fd
1 parent 4f9a6a7
commit 612a1fd
Showing 1 changed file with 45 additions and 44 deletions.
diff --git a/entrypoint.sh b/entrypoint.sh
@@ -1,26 +1,26 @@
 #!/busybox/sh
 set -e pipefail
-if [[ "$INPUT_DEBUG" == "true" ]]; then
+if [ "$INPUT_DEBUG" = "true" ]; then
     set -o xtrace
 fi
 
-export REGISTRY=${INPUT_REGISTRY:-"docker.io"}
-export IMAGE=${INPUT_IMAGE}
-export BRANCH=$(echo ${GITHUB_REF} | sed -E "s/refs\/(heads|tags)\///g" | sed -e "s/\//-/g")
-export TAG=${INPUT_TAG:-$([ "$BRANCH" == "master" ] && echo latest || echo $BRANCH)}
-export TAG=${TAG:-"latest"}
-export TAG=${TAG#$INPUT_STRIP_TAG_PREFIX}
-export USERNAME=${INPUT_USERNAME:-$GITHUB_ACTOR}
-export PASSWORD=${INPUT_PASSWORD:-$GITHUB_TOKEN}
-export REPOSITORY=$IMAGE
-export IMAGE=$IMAGE:$TAG
-export CONTEXT_PATH=${INPUT_PATH}
-
-if [[ "$INPUT_TAG_WITH_LATEST" == "true" ]]; then
-    export IMAGE_LATEST="$REPOSITORY:latest"
+export REGISTRY="${INPUT_REGISTRY:-'docker.io'}"
+export IMAGE="$INPUT_IMAGE"
+export BRANCH=$(echo "$GITHUB_REF" | sed -E "s/refs\/(heads|tags)\///g" | sed -e "s/\//-/g")
+export TAG=${INPUT_TAG:-$([ "$BRANCH" = "master" ] && echo latest || echo "$BRANCH")}
+export TAG="${TAG:-'latest'}"
+export TAG="${TAG#$INPUT_STRIP_TAG_PREFIX}"
+export USERNAME="${INPUT_USERNAME:-$GITHUB_ACTOR}"
+export PASSWORD="${INPUT_PASSWORD:-$GITHUB_TOKEN}"
+export REPOSITORY="$IMAGE"
+export IMAGE="${IMAGE}:${TAG}"
+export CONTEXT_PATH="$INPUT_PATH"
+
+if [ "$INPUT_TAG_WITH_LATEST" = "true" ]; then
+    export IMAGE_LATEST="${REPOSITORY}:latest"
 fi
 
-function ensure() {
+ensure() {
     if [ -z "${1}" ]; then
         echo >&2 "Unable to find the ${2} variable. Did you set with.${2}?"
         exit 1
@@ -34,46 +34,46 @@ ensure "${IMAGE}" "image"
 ensure "${TAG}" "tag"
 ensure "${CONTEXT_PATH}" "path"
 
-if [ "$REGISTRY" == "ghcr.io" ]; then
+if [ "$REGISTRY" = "ghcr.io" ]; then
     IMAGE_NAMESPACE="$(echo $GITHUB_REPOSITORY | tr '[:upper:]' '[:lower:]')"
     # Set `/` separator, unless image is pre-fixed with dash or slash
     [ -n "$REPOSITORY" ] && [[ ! "$REPOSITORY" =~ ^[-/] ]] && SEPARATOR="/"
     export IMAGE="$IMAGE_NAMESPACE$SEPARATOR$IMAGE"
     export REPOSITORY="$IMAGE_NAMESPACE$SEPARATOR$REPOSITORY"
 
-    if [ ! -z $IMAGE_LATEST ]; then
-        export IMAGE_LATEST="$IMAGE_NAMESPACE$SEPARATOR$IMAGE_LATEST"
+    if [ -n "$IMAGE_LATEST" ]; then
+        export IMAGE_LATEST="${IMAGE_NAMESPACE}/${IMAGE_LATEST}"
     fi
 
-    if [ ! -z $INPUT_CACHE_REGISTRY ]; then
-        export INPUT_CACHE_REGISTRY="$REGISTRY/$IMAGE_NAMESPACE/$INPUT_CACHE_REGISTRY"
+    if [ -n "$INPUT_CACHE_REGISTRY" ]; then
+        export INPUT_CACHE_REGISTRY="${REGISTRY}/${IMAGE_NAMESPACE}/${INPUT_CACHE_REGISTRY}"
     fi
 fi
 
-if [ "$REGISTRY" == "docker.io" ]; then
+if [ "$REGISTRY" = "docker.io" ]; then
     export REGISTRY="index.${REGISTRY}/v1/"
 else
-    export IMAGE="$REGISTRY/$IMAGE"
+    export IMAGE="${REGISTRY}/${IMAGE}"
 
-    if [ ! -z $IMAGE_LATEST ]; then
-        export IMAGE_LATEST="$REGISTRY/$IMAGE_LATEST"
+    if [ -n "$IMAGE_LATEST" ]; then
+        export IMAGE_LATEST="${REGISTRY}/${IMAGE_LATEST}"
     fi
 fi
 
-export CACHE=${INPUT_CACHE:+"--cache=true"}
-export CACHE=$CACHE${INPUT_CACHE_TTL:+" --cache-ttl=$INPUT_CACHE_TTL"}
-export CACHE=$CACHE${INPUT_CACHE_REGISTRY:+" --cache-repo=$INPUT_CACHE_REGISTRY"}
-export CACHE=$CACHE${INPUT_CACHE_DIRECTORY:+" --cache-dir=$INPUT_CACHE_DIRECTORY"}
+export CACHE="${INPUT_CACHE:+'--cache=true'}"
+export CACHE="$CACHE"${INPUT_CACHE_TTL:+" --cache-ttl=$INPUT_CACHE_TTL"}
+export CACHE="$CACHE"${INPUT_CACHE_REGISTRY:+" --cache-repo=$INPUT_CACHE_REGISTRY"}
+export CACHE="$CACHE"${INPUT_CACHE_DIRECTORY:+" --cache-dir=$INPUT_CACHE_DIRECTORY"}
 export CONTEXT="--context $GITHUB_WORKSPACE/$CONTEXT_PATH"
 export DOCKERFILE="--dockerfile $CONTEXT_PATH/${INPUT_BUILD_FILE:-Dockerfile}"
 export TARGET=${INPUT_TARGET:+"--target=$INPUT_TARGET"}
 export DIGEST="--digest-file /kaniko/digest --image-name-tag-with-digest-file=/kaniko/image-tag-digest"
 
-if [ ! -z $INPUT_SKIP_UNCHANGED_DIGEST ]; then
+if [ -n "$INPUT_SKIP_UNCHANGED_DIGEST" ]; then
     export DESTINATION="--no-push --tarPath image.tar --destination $IMAGE"
 else
     export DESTINATION="--destination $IMAGE"
-    if [ ! -z $IMAGE_LATEST ]; then
+    if [ -n "$IMAGE_LATEST" ]; then
         export DESTINATION="$DESTINATION --destination $IMAGE_LATEST"
     fi
 fi
@@ -98,33 +98,34 @@ kaniko_cmd="/kaniko/executor ${ARGS} --reproducible --force"
 echo "Running kaniko command ${kaniko_cmd}"
 eval "${kaniko_cmd}"
 
-echo "image=$IMAGE" >> $GITHUB_OUTPUT
-echo "digest=$(cat /kaniko/digest)" >> $GITHUB_OUTPUT
-echo "image-tag-digest=$(cat /kaniko/image-tag-digest)" >> $GITHUB_OUTPUT
+echo "image=$IMAGE" >> "$GITHUB_OUTPUT"
+echo "digest=$(cat /kaniko/digest)" >> "$GITHUB_OUTPUT"
+echo "image-tag-digest=$(cat /kaniko/image-tag-digest)" >> "$GITHUB_OUTPUT"
 
-if [ ! -z $INPUT_SKIP_UNCHANGED_DIGEST ]; then
-    export DIGEST=$(cat /kaniko/digest)
 
-    /kaniko/crane auth login $REGISTRY -u $USERNAME -p $PASSWORD
+if [ -n "$INPUT_SKIP_UNCHANGED_DIGEST" ]; then
+    export DIGEST="$(cat /kaniko/digest)"
 
-    export REMOTE=$(crane digest $REGISTRY/${REPOSITORY}:latest)
+    /kaniko/crane auth login "$REGISTRY" -u "$USERNAME" -p "$PASSWORD"
 
-    if [ "$DIGEST" == "$REMOTE" ]; then
-        echo "refreshed=false" >> $GITHUB_OUTPUT
+    export REMOTE=$(crane digest "${REGISTRY}/${REPOSITORY}:latest")
+
+    if [ "$DIGEST" = "$REMOTE" ]; then
+        echo "refreshed=false" >> "$GITHUB_OUTPUT"
         echo "Digest hasn't changed, skipping, $DIGEST"
         echo "Done 🎉️"
         exit 0
     fi
 
     echo "Pushing image..."
 
-    /kaniko/crane push image.tar $IMAGE
+    /kaniko/crane push image.tar "$IMAGE"
 
-    if [ ! -z $IMAGE_LATEST ]; then
+    if [ -n "$IMAGE_LATEST" ]; then
         echo "Tagging latest..."
-        /kaniko/crane tag $IMAGE latest
+        /kaniko/crane tag "$IMAGE" latest
     fi
 
-    echo "refreshed=false" >> $GITHUB_OUTPUT
+    echo "refreshed=false" >> "$GITHUB_OUTPUT"
     echo "Done 🎉️"
 fi