y-build

#!/usr/bin/env bash
[ -z "$DEBUG" ] || set -x
set -eo pipefail

# For example: --opt filename=test.Dockerfile
BUILDCTL_OPTS="$@"

FILENAME=""
for arg in $BUILDCTL_OPTS; do
  case "$arg" in
    --opt)
      opt=true ;;
    filename=*)
      [ -z "$opt" ] && echo "filename arg without preceding --opt: $arg" && exit 1
      FILENAME="$(echo $arg | cut -d= -f2-)"
      [ -z "$FILENAME" ] && echo "Failed to extract filename from arg $arg" && exit 1
      opt="" ;;
    *)
      opt="" ;;
  esac
done

if [ -n "$FILENAME" ]; then
  stat $FILENAME >/dev/null
  stat $FILENAME.dockerignore >/dev/null || (echo "Missing .dockerignore for $FILENAME" && exit 1)
  DOCKERFILE_SYNTAX="$(head -n 1 $FILENAME)"
fi

case "$DOCKERFILE_SYNTAX" in
  "# syntax=ystack/v1-base:"*)
    DOCKERFILE_BASE=$(echo $DOCKERFILE_SYNTAX | cut -d: -f2)
    ;;
  "# syntax=docker/dockerfile:"*)
    ;;
  *)
    ;;
esac

# Needed as long as we modify local files
function cleanup {
  if [ -n "$DOCKERFILE_BASE" ]; then
    mv $FILENAME.y-build.tmp $FILENAME
    mv $FILENAME.y-build.tmp.dockerignore $FILENAME.dockerignore
    rm "$DOCKERFILE_TMP.dockerignore"
  fi
}
trap cleanup EXIT

if [ -n "$DOCKERFILE_BASE" ]; then
  DOCKERFILE_DIR=$(dirname $FILENAME)
  echo "y-stack dockerfile syntax detected base: $DOCKERFILE_BASE (in $DOCKERFILE_DIR/)"
  (cd $DOCKERFILE_DIR;
    stat $DOCKERFILE_BASE >/dev/null;
    stat $DOCKERFILE_BASE.dockerignore >/dev/null || (echo "Missing .dockerignore for $DOCKERFILE_BASE" && exit 1)
    )
  head -n 1 $FILENAME.dockerignore | grep '*' >/dev/null || (echo "$FILNEAME.dockerignore must start with a * line when using a base" && exit 1)
  DOCKERFILE_TMP=$(mktemp)
  (cd $DOCKERFILE_DIR;
    cat $DOCKERFILE_BASE > $DOCKERFILE_TMP;
    echo "# ^^^ ystack base $DOCKERFILE_BASE ____ $FILENAME" >> $DOCKERFILE_TMP
    cat $DOCKERFILE_BASE.dockerignore > $DOCKERFILE_TMP.dockerignore;
    echo "# ^^^ ystack base $DOCKERFILE_BASE.dockerignore ____ $FILENAME.dockerignore" >> $DOCKERFILE_TMP.dockerignore
  )
  cat $FILENAME >> $DOCKERFILE_TMP;
  cat $FILENAME.dockerignore | tail -n+2 >> $DOCKERFILE_TMP.dockerignore;
  mv $FILENAME $FILENAME.y-build.tmp
  mv $FILENAME.dockerignore $FILENAME.y-build.tmp.dockerignore
  cat $DOCKERFILE_TMP > $FILENAME
  cat $DOCKERFILE_TMP.dockerignore > $FILENAME.dockerignore
  [ -z "$DEBUG" ] || ls -l $FILENAME*
  [ -z "$DEBUGDEBUG" ] || cat $DOCKERFILE_TMP
  [ -z "$DEBUGDEBUG" ] || cat $DOCKERFILE_TMP.dockerignore
  # Default to not exporting cache when doing full builds, but add cache info to manifest
  # but not if import cache is overridden because that's probably a different image URL
  [ -z "$EXPORT_CACHE" ] && [ -z "$IMPORT_CACHE" ] && EXPORT_CACHE="--export-cache type=inline" && echo "Default EXPORT_CACHE changed to: $EXPORT_CACHE"
fi

# Settings
DEFAULT_REGISTRY=builds-registry.ystack.svc.cluster.local
[ -z "$BUILDS_REGISTRY" ] && BUILDS_REGISTRY=$DEFAULT_REGISTRY
[ -z "$PUSH_REGISTRY" ]   && PUSH_REGISTRY=$DEFAULT_REGISTRY
[ -z "$BUILDKIT_HOST" ] && BUILDKIT_HOST=tcp://buildkitd.ystack.svc.cluster.local:8547
[ -z "$REGISTRY_PROBE_CONNECT_TIMEOUT" ] && REGISTRY_PROBE_CONNECT_TIMEOUT=3

if [ "$(curl -s --connect-timeout "$REGISTRY_PROBE_CONNECT_TIMEOUT" http://$BUILDS_REGISTRY/v2/)" != "{}" ]
then
  echo "ERROR Skaffold need local access to the builds registry for digest lookup"
  echo "Registry: $BUILDS_REGISTRY"
  echo "Look for y-stack's ingress or port-forward utilities"
  exit 1
fi

# Envs from Skaffold build custom
# (but for now we simply ignore PUSH_IMAGE as it has no clear significance for in-cluster builds)
[ -z "$BUILD_CONTEXT" ] && {
  echo "No BUILD_CONTEXT env (from for example Skaffold). Using first arg like traditional Docker builds do."
  BUILD_CONTEXT="$1"
  [ -z "$BUILD_CONTEXT" ] && echo "... and no first arg either. Exiting." && exit 1
}
[ -z "$BUILD_CONTEXT_DOCKERFILE" ] && BUILD_CONTEXT_DOCKERFILE="$BUILD_CONTEXT" # Do these ever differ?

[ -z "$IMAGE" ] && {
  name=${PWD##*/}
  IMAGE="$BUILDS_REGISTRY/y-stack-temp-builds/$name"
  echo "No IMAGE env (from for example Skaffold). Guessing: $IMAGE"
}

# Hooks, evaluating reliance on PATH for that
command -v y-hook-build-pre && cd $BUILD_CONTEXT && y-hook-build-pre

IMAGE=$IMAGE
case "$IMAGE" in
  $BUILDS_REGISTRY/* ) ;;
  $BUILDS_REGISTRY:80/* ) ;;
  $PUSH_REGISTRY/* ) ;;
  $PUSH_REGISTRY:80/* ) ;;
  * ) echo "Output is restricted to PUSH_REGISTRY=$PUSH_REGISTRY. Got: $IMAGE" && exit 1 ;;
esac

[ -n "$SOURCE_DATE_EPOCH" ] || SOURCE_DATE_EPOCH=0

OUTPUT="type=image,name=$IMAGE,push=true"

[ "$REWRITE_TIMESTAMP" != "true" ] || OUTPUT="$OUTPUT,rewrite-timestamp=true"
[ "$SOURCE_DATE_EPOCH" != "-1" ] || SOURCE_DATE_EPOCH=""

BUILD_TAG="$(echo $IMAGE | awk -F/ '{print $NF}' | awk -F@ '{print $1}' | awk -F: '{print $2}')"

# https://github.com/Yolean/build-contract/blob/a7e1a96ccec79bf413d604c344679f7439c34b49/build-contract#L21
GIT_COMMIT=$(git rev-parse --verify --short HEAD 2>/dev/null || echo '')
if [[ ! -z "$GIT_COMMIT" ]]; then
  GIT_STATUS=$(git status --untracked-files=no --porcelain=v2)
  if [[ ! -z "$GIT_STATUS" ]]; then
    GIT_COMMIT="$GIT_COMMIT-dirty"
  fi
fi

REGISTRY_CACHE_DEFAULT=$(echo $IMAGE | sed "s|[^/]*|$BUILDS_REGISTRY/ystack-buildcache|" | sed "s/:$BUILD_TAG//")
[ -z "$BUILDKIT_CACHE" ] && BUILDKIT_CACHE="type=registry,ref=$REGISTRY_CACHE_DEFAULT"
[ -z "$IMPORT_CACHE" ] && IMPORT_CACHE="--import-cache=$BUILDKIT_CACHE"
[ -z "$EXPORT_CACHE" ] && EXPORT_CACHE="--export-cache=$BUILDKIT_CACHE,mode=max"
[ "$IMPORT_CACHE" = "false" ] && IMPORT_CACHE=""
[ "$EXPORT_CACHE" = "false" ] && EXPORT_CACHE=""

OPT_PLATFORM=""
[ -z "$PLATFORMS" ] || OPT_PLATFORM="--opt platform=$PLATFORMS"

echo "Build command:"
set -x
SOURCE_DATE_EPOCH="$SOURCE_DATE_EPOCH" y-buildctl \
  --addr $BUILDKIT_HOST \
  build \
    --frontend dockerfile.v0 \
    --local context="$BUILD_CONTEXT" \
    --local dockerfile="$BUILD_CONTEXT_DOCKERFILE" \
    $OPT_PLATFORM \
    --opt build-arg:build_tag=$BUILD_TAG \
    --opt build-arg:git_commit=$GIT_COMMIT \
    $IMPORT_CACHE \
    $EXPORT_CACHE \
    $BUILDCTL_OPTS \
    --output "$OUTPUT"