From 92de014466236119765f9eda835414df822833b4 Mon Sep 17 00:00:00 2001
From: Guillaume Galy <ggaly@gatling.io>
Date: Tue, 26 Mar 2024 08:15:28 +0100
Subject: [PATCH] fix: Downgrade Protobuf from 4.x to 3.x

Motivation:

- grpc-java is not fully compatible with Protobuf 4; see: https://github.com/grpc/grpc-java/issues/11015
- Protobuf 4 breaks our demo server due to an incompatibility between the generated code and what the grpc-java library expects.

Modifications:

- Downgrade to Protobuf 3 on all projects.
- Prevent upgrade to Protobuf 4 in dependabot.yml (note: scala-steward doesn't seem to pick up Protobuf updates anyway, probably because it's not configured as a library dependency per se).

Result:

Stick to Protobuf 3 for now.
---
 .github/dependabot.yml   | 15 +++++++++++++++
 java/gradle/build.gradle |  2 +-
 java/maven/pom.xml       |  2 +-
 kotlin/maven/pom.xml     |  2 +-
 server/build.gradle      |  2 +-
 5 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/.github/dependabot.yml b/.github/dependabot.yml
index 4e8165f..a96d073 100644
--- a/.github/dependabot.yml
+++ b/.github/dependabot.yml
@@ -7,6 +7,9 @@ updates:
     schedule:
       interval: "weekly"
       day: "sunday"
+    ignore:
+      - dependency-name: "com.google.protobuf:protoc"
+        versions: ['>= 4'] # https://github.com/grpc/grpc-java/issues/11015
   - package-ecosystem: "maven"
     directory: "/java/maven"
     commit-message:
@@ -14,6 +17,9 @@ updates:
     schedule:
       interval: "weekly"
       day: "sunday"
+    ignore:
+      - dependency-name: "com.google.protobuf:protoc"
+        versions: ['>= 4'] # https://github.com/grpc/grpc-java/issues/11015
   - package-ecosystem: "gradle"
     directory: "/kotlin/gradle"
     commit-message:
@@ -25,6 +31,9 @@ updates:
     schedule:
       interval: "weekly"
       day: "sunday"
+    ignore:
+      - dependency-name: "com.google.protobuf:protoc"
+        versions: ['>= 4'] # https://github.com/grpc/grpc-java/issues/11015
   - package-ecosystem: "maven"
     directory: "/kotlin/maven"
     commit-message:
@@ -32,6 +41,9 @@ updates:
     schedule:
       interval: "weekly"
       day: "sunday"
+    ignore:
+      - dependency-name: "com.google.protobuf:protoc"
+        versions: ['>= 4'] # https://github.com/grpc/grpc-java/issues/11015
   - package-ecosystem: "gradle"
     directory: "/server"
     commit-message:
@@ -43,3 +55,6 @@ updates:
     schedule:
       interval: "weekly"
       day: "sunday"
+    ignore:
+      - dependency-name: "com.google.protobuf:protoc"
+        versions: ['>= 4'] # https://github.com/grpc/grpc-java/issues/11015
diff --git a/java/gradle/build.gradle b/java/gradle/build.gradle
index 3dc56f9..928749c 100644
--- a/java/gradle/build.gradle
+++ b/java/gradle/build.gradle
@@ -43,7 +43,7 @@ sourceSets {
 
 protobuf {
   protoc {
-    artifact = "com.google.protobuf:protoc:4.26.0"
+    artifact = "com.google.protobuf:protoc:3.25.3"
   }
   plugins {
     grpc {
diff --git a/java/maven/pom.xml b/java/maven/pom.xml
index f2844b0..5580ba9 100644
--- a/java/maven/pom.xml
+++ b/java/maven/pom.xml
@@ -19,7 +19,7 @@
         <gatling-maven-plugin.version>4.8.2</gatling-maven-plugin.version>
         <maven-compiler-plugin.version>3.13.0</maven-compiler-plugin.version>
         <maven-jar-plugin.version>3.3.0</maven-jar-plugin.version>
-        <protobuf.version>3.24.2</protobuf.version>
+        <protobuf.version>3.25.3</protobuf.version>
         <protobuf-maven-plugin.version>0.6.1</protobuf-maven-plugin.version>
         <protoc-gen-grpc-java.version>1.57.2</protoc-gen-grpc-java.version>
         <spotless.version>2.43.0</spotless.version>
diff --git a/kotlin/maven/pom.xml b/kotlin/maven/pom.xml
index e10b314..d8bebc2 100644
--- a/kotlin/maven/pom.xml
+++ b/kotlin/maven/pom.xml
@@ -21,7 +21,7 @@
         <maven-compiler-plugin.version>3.13.0</maven-compiler-plugin.version>
         <maven-jar-plugin.version>3.3.0</maven-jar-plugin.version>
         <maven-resources-plugin.version>3.3.1</maven-resources-plugin.version>
-        <protobuf.version>4.26.0</protobuf.version>
+        <protobuf.version>3.25.3</protobuf.version>
         <protobuf-maven-plugin.version>0.6.1</protobuf-maven-plugin.version>
         <protoc-gen-grpc-java.version>1.57.2</protoc-gen-grpc-java.version>
         <spotless.version>2.43.0</spotless.version>
diff --git a/server/build.gradle b/server/build.gradle
index 1285347..9b11794 100644
--- a/server/build.gradle
+++ b/server/build.gradle
@@ -27,7 +27,7 @@ idea {
 
 protobuf {
   protoc {
-    artifact = "com.google.protobuf:protoc:4.26.0"
+    artifact = "com.google.protobuf:protoc:3.25.3"
   }
   plugins {
     grpc {