Initial draft of plugin.

entrypoint.sh

@@ -0,0 +1,102 @@
+#!/usr/bin/env bash
+set -eu;
+
+##
+## check input
+##
+
+if [[ -n "${PLUGIN_ENV_FILE:-}" ]]; then
+	if [[ ! -f "$PLUGIN_ENV_FILE" ]]; then
+		echo "Env file $PLUGIN_ENV_FILE not found."
+		exit 1
+	fi
+	# shellcheck source=/dev/null
+	source "$PLUGIN_ENV_FILE"
+fi
+
+BUILDCTL_CONTEXT=${PLUGIN_CONTEXT:-$(pwd)}
+BUILDCTL_DOCKERFILE=$(dirname "${PLUGIN_DOCKERFILE:-$BUILDCTL_CONTEXT/Dockerfile}")
+if [[ ! -f $BUILDCTL_DOCKERFILE/Dockerfile ]]; then
+	echo "Dockerfile $BUILDCTL_DOCKERFILE/Dockerfile not found!"
+	exit 1
+fi
+
+BUILDCTL_FRONTEND=${PLUGIN_FRONTEND:-dockerfile.v0}
+if [[ "$BUILDCTL_FRONTEND" != "dockerfile.v0" ]]; then
+	echo "Only frontend 'dockerfile.v0' tested and supported yet."
+	exit 1
+fi
+
+SOURCE_DATE_EPOCH=${PLUGIN_SOURCE_DATE_EPOCH:-0}
+
+if [[ -n "${PLUGIN_AUTH:-}" ]]; then
+	echo "$PLUGIN_AUTH" | jq -r 'to_entries|map({(.key):{"auth":(.value.username+":"+.value.password)|@base64}})|add|{"auths":.}' > "$HOME/.docker/config.json"
+	echo "Stored credentials at $HOME/.docker/config.json"
+	echo
+fi
+
+##
+## build command
+##
+
+COMMAND="buildctl build"
+if [[ -n "${PLUGIN_ADDR:-}" ]]; then
+	COMMAND+=" --addr=$PLUGIN_ADDR"
+fi
+COMMAND+=" --frontend=$BUILDCTL_FRONTEND"
+COMMAND+=" --local=context=$BUILDCTL_CONTEXT"
+COMMAND+=" --local=dockerfile=$BUILDCTL_DOCKERFILE"
+if [[ -n  "${PLUGIN_PLATFORM:-}" ]]; then
+	COMMAND+=" --opt=platform=$PLUGIN_PLATFORM"
+fi
+if [[ -n  "${PLUGIN_TARGET:-}" ]]; then
+	COMMAND+=" --opt=target=$PLUGIN_TARGET"
+fi
+if [[ -n  "${PLUGIN_BUILD_ARGS:-}" ]]; then
+	COMMAND+="$(eval "echo \"${PLUGIN_BUILD_ARGS//\"/\\\"}\"" | jq --join-output 'keys[] as $k|" --opt=build-arg:\($k)=\(.[$k])"')"
+fi
+COMMAND+=" --opt=build-arg:SOURCE_DATE_EPOCH=$SOURCE_DATE_EPOCH"
+
+# https://github.com/moby/buildkit/blob/master/README.md#output
+if [[ -n "${PLUGIN_NAME:-}" ]]; then
+	PLUGIN_NAME="$(eval "echo \"${PLUGIN_NAME//\"/\\\"}\"")"
+	OUTPUT="type=image"
+	if [[ "$PLUGIN_NAME" =~ .*,.* ]]; then
+		# https://github.com/moby/buildkit/issues/797#issuecomment-1561601104
+		OUTPUT+=",\"name=$PLUGIN_NAME\""
+	else
+		OUTPUT+=",name=$PLUGIN_NAME"
+	fi
+	if [[ -n "${PLUGIN_ANNOTATION:-}" ]]; then
+		OUTPUT+="$(eval "echo \"${PLUGIN_ANNOTATION//\"/\\\"}\"" | jq --join-output 'keys[] as $k|",annotation.\($k)=\(.[$k])"')"
+	fi
+	OUTPUT+=",push=${PLUGIN_PUSH:-true},oci-mediatypes=true,compression=estargz,compression-level=9,rewrite-timestamp=true"
+	COMMAND+=" --output='$OUTPUT'"
+fi
+
+##
+## execute command
+##
+
+echo
+echo Reproduce with docker:
+echo
+echo "  docker buildx build ${PLUGIN_CONTEXT:-.} \\"
+if [[ -n  "${PLUGIN_TARGET:-}" ]]; then
+	echo "    --target=$PLUGIN_TARGET \\"
+fi
+echo "    --no-cache \\"
+echo "    --provenance=false \\"
+echo "    --build-arg=SOURCE_DATE_EPOCH=$SOURCE_DATE_EPOCH \\"
+if [[ -n  "${PLUGIN_PLATFORM:-}" ]]; then
+	echo "    --platform=$PLUGIN_PLATFORM \\"
+fi
+if [[ -n "${OUTPUT:-}" ]]; then
+	echo "    --output='${OUTPUT//push=true/push=false}'"
+fi
+echo
+echo Running now:
+echo
+echo -e "  ${COMMAND// --/ \\n    --}"
+echo
+eval "$COMMAND"