CDRIVER-5497 implement downstream RPM spec check (#1551)

Co-authored-by: Kevin Albertson <[email protected]>

.evergreen/generated_configs/legacy-config.yml

@@ -879,6 +879,15 @@ tasks:
       content_type: ${content_type|application/x-gzip}
 - name: rpm-package-build
   commands:
+  - command: shell.exec
+    type: test
+    params:
+      working_dir: mongoc
+      shell: bash
+      script: |-
+        set -o errexit
+        export IS_PATCH="${is_patch}"
+        sh .evergreen/scripts/check_rpm_spec.sh
   - command: shell.exec
     type: test
     params:

.evergreen/legacy_config_generator/evergreen_config_lib/tasks.py

@@ -328,6 +328,7 @@ def __init__(
     NamedTask(
         "rpm-package-build",
         commands=[
+            shell_mongoc('export IS_PATCH="${is_patch}"\n' "sh .evergreen/scripts/check_rpm_spec.sh"),
             shell_mongoc("sh .evergreen/scripts/build_snapshot_rpm.sh"),
             s3_put(
                 local_file="rpm.tar.gz",

.evergreen/scripts/check_rpm_spec.sh

@@ -0,0 +1,43 @@
+#!/usr/bin/env bash
+
+#
+# Copyright 2024 MongoDB, Inc.
+#
+# Licensed 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.
+#
+
+set -o errexit
+
+#
+# check_rpm_spec.sh - Check if our RPM spec matches downstream's
+#
+# Supported/used environment variables:
+#   IS_PATCH    If "true", this is an Evergreen patch build.
+
+
+on_exit () {
+  if [ -n "${SPEC_FILE}" ]; then
+    rm -f "${SPEC_FILE}"
+  fi
+}
+trap on_exit EXIT
+
+if [ "${IS_PATCH}" = "true" ]; then
+   echo "This is a patch build...skipping RPM spec check"
+   exit
+fi
+
+SPEC_FILE=$(mktemp --tmpdir -u mongo-c-driver.XXXXXXXX.spec)
+curl --retry 5 https://src.fedoraproject.org/rpms/mongo-c-driver/raw/rawhide/f/mongo-c-driver.spec -sS --max-time 120 --fail --output "${SPEC_FILE}"
+
+diff -q .evergreen/etc/mongo-c-driver.spec "${SPEC_FILE}" || (echo "Synchronize RPM spec from downstream to fix this failure. See instructions here: https://docs.google.com/document/d/1ItyBC7VN383zNXu3oUOQJYR7adfYI8ECjLMJ5kqA9X8/edit#heading=h.ahdrr3b5xv3"; exit 1)