generate-protobuf.sh

#!/bin/bash

set -euo pipefail

# We use the shaded protobuf JAR from the protobuf-shaded module.
# I could not figure out how to use a protoc Maven plugin to use the shaded module,
# so I ran this command to generate the sources manually.

TARGET_DIR=$1
PROTO_DIR=src/main/protobuf
PROTOBUF_VERSION_STRING=$2
PROTOBUF_VERSION="${PROTOBUF_VERSION_STRING//_/.}"

echo "Generating protobuf sources for version $PROTOBUF_VERSION in $TARGET_DIR"

rm -rf "$TARGET_DIR"
mkdir -p "$TARGET_DIR"
rm -rf $PROTO_DIR || true
mkdir -p $PROTO_DIR

OLD_PACKAGE=$(sed -nE 's/.*extends (io\.prometheus\.metrics\.expositionformats\.generated\.[^ ]*?)\.Metrics.*/\1/p' src/main/java/io/prometheus/metrics/expositionformats/generated/Metrics.java)
PACKAGE="io.prometheus.metrics.expositionformats.generated.com_google_protobuf_${PROTOBUF_VERSION_STRING}"

SUPERCLASS_FILE="src/main/java/io/prometheus/metrics/expositionformats/generated/Metrics.java"
if [[ $OLD_PACKAGE != "$PACKAGE" ]]; then
	echo "Replacing package $OLD_PACKAGE with $PACKAGE in $SUPERCLASS_FILE"
	sed -i "s/$OLD_PACKAGE/$PACKAGE/g" "$SUPERCLASS_FILE"
fi

curl -sL https://raw.githubusercontent.com/prometheus/client_model/master/io/prometheus/client/metrics.proto -o $PROTO_DIR/metrics.proto

sed -i "s/java_package = \"io.prometheus.client\"/java_package = \"$PACKAGE\"/" $PROTO_DIR/metrics.proto
protoc --java_out "$TARGET_DIR" $PROTO_DIR/metrics.proto
sed -i '1 i\//CHECKSTYLE:OFF: checkstyle' "$(find src/main/generated/io -type f)"
sed -i -e $'$a\\\n//CHECKSTYLE:ON: checkstyle' "$(find src/main/generated/io -type f)"

GENERATED_FILE="$TARGET_DIR/${PACKAGE//\.//}/Metrics.java"
sed -i 's/public final class Metrics/public class Metrics/' "$GENERATED_FILE"
sed -i 's/private Metrics() {}/protected Metrics() {}/' "$GENERATED_FILE"

GENERATED_WITH=$(grep -oP '\/\/ Protobuf Java Version: \K.*' "$TARGET_DIR/${PACKAGE//\.//}"/Metrics.java)

function help() {
	echo "Please use https://mise.jdx.dev/ - this will use the version specified in mise.toml"
	echo "Generated protobuf sources are not up-to-date. Please run 'mise run generate' and commit the changes."
	echo "NOTE:"
	echo "1. You should only run 'mise run generate' in a PR from renovate"
	echo "2. The PR should update both '<protobuf-java.version>' in pom.xml and protoc in mise.toml"
	echo "   - but at least <protobuf-java.version>. If not, wait until renovate updates the PR."
}

if [[ $GENERATED_WITH != "$PROTOBUF_VERSION" ]]; then
	echo "Generated protobuf sources version $GENERATED_WITH does not match provided version $PROTOBUF_VERSION"
	help
	exit 1
fi

STATUS=$(git status --porcelain)
if [[ ${REQUIRE_PROTO_UP_TO_DATE:-false} == "true" && -n "$STATUS" ]]; then
	help
	echo "Local changes:"
	echo "$STATUS"
	exit 1
fi