ci: git-fallback for tombstone proto schema check

scripts/check-tombstone-proto-schema.sh

@@ -1,25 +1,219 @@
 #!/usr/bin/env bash
-set -euo pipefail
+set -Eeuo pipefail
 
 TRACKED_COMMIT="981d145117e8992842cdddee555c57e60c7a220a"
+REMOTE_URL='https://android.googlesource.com/platform/system/core'
+REMOTE_BRANCH='main'
+PROTO_PATH='debuggerd/proto/tombstone.proto'
+GITILES_REF="refs/heads/${REMOTE_BRANCH}"
+GITILES_LOG_URL="${REMOTE_URL}/+log/${GITILES_REF}/${PROTO_PATH}?format=JSON"
 
-# tail -n +2 to remove the magic anti-XSSI prefix from the Gitiles JSON response
-LATEST_COMMIT=$(curl -sf \
-  'https://android.googlesource.com/platform/system/core/+log/refs/heads/main/debuggerd/proto/tombstone.proto?format=JSON' \
-  | tail -n +2 \
-  | jq -r '.log[0].commit')
+MODE=auto
+case "${1:-}" in
+  "")
+    ;;
+  --git-only)
+    MODE=git
+    ;;
+  --gitiles-only)
+    MODE=gitiles
+    ;;
+  *)
+    echo "Usage: $0 [--git-only|--gitiles-only]" >&2
+    exit 2
+    ;;
+esac
 
-if [ -z "$LATEST_COMMIT" ] || [ "$LATEST_COMMIT" = "null" ]; then
-  echo "ERROR: Failed to fetch latest commit from Gitiles" >&2
-  exit 1
-fi
+TEMP_FILES=()
+TEMP_DIRS=()
+LATEST_COMMIT=""
 
-echo "Tracked commit: $TRACKED_COMMIT"
-echo "Latest commit:  $LATEST_COMMIT"
+error() {
+  echo "ERROR: $*" >&2
+}
 
-if [ "$LATEST_COMMIT" != "$TRACKED_COMMIT" ]; then
-  echo "Schema has been updated! Latest: https://android.googlesource.com/platform/system/core/+/${LATEST_COMMIT}/debuggerd/proto/tombstone.proto"
-  exit 1
-fi
+show_output() {
+  local label=$1
+  local file=$2
 
-echo "Schema is up to date."
+  if [ -s "$file" ]; then
+    echo "$label:" >&2
+    sed 's/^/  /' "$file" >&2
+  fi
+}
+
+require_command() {
+  local command_name=$1
+
+  if ! command -v "$command_name" >/dev/null 2>&1; then
+    error "Required command not found: $command_name"
+    return 1
+  fi
+}
+
+make_temp_file() {
+  local file
+  file=$(mktemp)
+  TEMP_FILES+=("$file")
+  printf '%s\n' "$file"
+}
+
+make_temp_dir() {
+  local dir
+  dir=$(mktemp -d)
+  TEMP_DIRS+=("$dir")
+  printf '%s\n' "$dir"
+}
+
+cleanup() {
+  local path
+
+  for path in "${TEMP_FILES[@]}"; do
+    rm -f "$path"
+  done
+
+  for path in "${TEMP_DIRS[@]}"; do
+    rm -rf "$path"
+  done
+}
+
+handle_unexpected_error() {
+  local exit_code=$?
+  error "Unexpected failure at line $1 while running: $2 (exit $exit_code)"
+  exit "$exit_code"
+}
+
+trap 'handle_unexpected_error "$LINENO" "$BASH_COMMAND"' ERR
+trap cleanup EXIT
+
+run_gitiles_check() {
+  local response_file
+  local stderr_file
+  local status
+
+  require_command curl || return 1
+  require_command jq || return 1
+
+  response_file=$(make_temp_file)
+  stderr_file=$(make_temp_file)
+
+  if curl -fsS "$GITILES_LOG_URL" -o "$response_file" 2>"$stderr_file"; then
+    :
+  else
+    status=$?
+    error "Failed to fetch Gitiles history from:"
+    error "  $GITILES_LOG_URL"
+    error "curl exited with status $status."
+    show_output "curl output" "$stderr_file"
+    return 1
+  fi
+
+  if LATEST_COMMIT=$(tail -n +2 "$response_file" | jq -er '.log[0].commit' 2>"$stderr_file"); then
+    :
+  else
+    status=$?
+    error "Failed to parse the latest commit from the Gitiles response."
+    error "jq exited with status $status."
+    show_output "jq output" "$stderr_file"
+    echo "Response preview:" >&2
+    head -n 20 "$response_file" >&2
+    return 1
+  fi
+
+  if [ -z "$LATEST_COMMIT" ]; then
+    error "Gitiles response did not contain a commit hash."
+    echo "Response preview:" >&2
+    head -n 20 "$response_file" >&2
+    return 1
+  fi
+}
+
+run_git_check() {
+  local repo_dir
+  local stderr_file
+  local status
+
+  require_command git || return 1
+
+  repo_dir=$(make_temp_dir)
+  stderr_file=$(make_temp_file)
+
+  if GIT_TERMINAL_PROMPT=0 git clone \
+    --quiet \
+    --filter=blob:none \
+    --single-branch \
+    --branch "$REMOTE_BRANCH" \
+    --no-checkout \
+    "$REMOTE_URL" "$repo_dir" 2>"$stderr_file"; then
+    :
+  else
+    status=$?
+    error "Failed to clone $REMOTE_BRANCH from:"
+    error "  $REMOTE_URL"
+    error "git clone exited with status $status."
+    show_output "git clone output" "$stderr_file"
+    return 1
+  fi
+
+  if LATEST_COMMIT=$(git -C "$repo_dir" log -n 1 --format=%H HEAD -- "$PROTO_PATH" 2>"$stderr_file"); then
+    :
+  else
+    status=$?
+    error "Failed to determine the latest commit that modified:"
+    error "  $PROTO_PATH"
+    error "git log exited with status $status."
+    show_output "git log output" "$stderr_file"
+    return 1
+  fi
+
+  if [ -z "$LATEST_COMMIT" ]; then
+    error "Git history did not contain a commit for:"
+    error "  $PROTO_PATH"
+    return 1
+  fi
+}
+
+report_result() {
+  echo "Tracked commit: $TRACKED_COMMIT"
+  echo "Latest commit:  $LATEST_COMMIT"
+
+  if [ "$LATEST_COMMIT" != "$TRACKED_COMMIT" ]; then
+    echo "Schema has been updated! Latest: ${REMOTE_URL}/+/${LATEST_COMMIT}/${PROTO_PATH}"
+    exit 1
+  fi
+
+  echo "Schema is up to date."
+}
+
+case "$MODE" in
+  auto)
+    if run_gitiles_check; then
+      report_result
+      exit 0
+    fi
+
+    echo "Falling back to git-based check." >&2
+    if run_git_check; then
+      report_result
+      exit 0
+    fi
+
+    exit 1
+    ;;
+  gitiles)
+    if run_gitiles_check; then
+      report_result
+      exit 0
+    fi
+
+    exit 1
+    ;;
+  git)
+    if run_git_check; then
+      report_result
+      exit 0
+    fi
+
+    exit 1
+    ;;
+esac