From e9c91448dcd44f61c5c6f36e0d018d2beabdd6b9 Mon Sep 17 00:00:00 2001
From: Denys Kuzmenko <dkuzmenko@cloudera.com>
Date: Fri, 25 Sep 2026 13:23:33 +0300
Subject: [PATCH] TEZ-4758: Add a buf configuration so Yetus bufcompat/buflint
 can run

- Yetus runs buf at the repository root with no config, so every cross-file import
  ("imported file does not exist" for import "DAGApiRecords.proto") fails and bufcompat
  votes -1 on the base branch before a patch is even applied. TEZ-4548 was the last proto
  change and predates the check; TEZ-4757 is the first patch to hit it
- One module per main proto directory, so tez-dag can import tez-api and tez-runtime-internals;
  the test fixture proto in tez-ext-service-tests is not a module, it has no compatibility contract
- breaking: WIRE. The payloads are internal wire messages; FILE would reject a same-number
  int32 -> int64 widening that is wire-compatible
- lint: MINIMAL minus PACKAGE_DEFINED. No Tez proto declares a package, and adding one
  renames every generated type and every message's fully-qualified name on the wire
- Verified with buf 1.50.0, the version Yetus rel/0.15.1 ships: build and lint clean on
  master, breaking clean for TEZ-4757 against master
---
 buf.yaml | 47 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 47 insertions(+)
 create mode 100644 buf.yaml

diff --git a/buf.yaml b/buf.yaml
new file mode 100644
index 0000000000..675d8ea679
--- /dev/null
+++ b/buf.yaml
@@ -0,0 +1,47 @@
+#
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+---
+# buf configuration for the Yetus bufcompat and buflint checks.
+# Each main proto directory is a module so cross-module imports resolve
+# (tez-dag imports tez-api and tez-runtime-internals). Test fixtures are
+# not modules.
+version: v2
+modules:
+  - path: tez-api/src/main/proto
+  - path: tez-dag/src/main/proto
+  - path: tez-mapreduce/src/main/proto
+  - path: tez-plugins/tez-protobuf-history-plugin/src/main/proto
+  - path: tez-runtime-internals/src/main/proto
+  - path: tez-runtime-library/src/main/proto
+lint:
+  use:
+    - MINIMAL
+  except:
+    # No Tez proto declares a package. Every file sets java_package, so
+    # adding one would not move the Java classes, but it changes every
+    # message's fully-qualified protobuf name -- descriptors, Any type
+    # URLs, what the history plugin persists -- which is not a lint fix.
+    - PACKAGE_DEFINED
+breaking:
+  # Tez protos are RPC (DAGClientAMProtocol), events and payloads between
+  # components of one Tez build, or bytes the history plugin persists.
+  # What must hold is wire compatibility, not generated-code source
+  # compatibility: FILE would reject int32 -> int64 on the same field
+  # number, which the wire accepts.
+  use:
+    - WIRE