ci: avoid unnecessary docker image pulls

scripts/ci-docker-pull-retry.sh

@@ -0,0 +1,42 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+if [[ "$#" -ne 1 || -z "${1// }" ]]; then
+  echo "usage: $0 <image>" >&2
+  exit 2
+fi
+
+image="$1"
+attempts="${OPENCLAW_DOCKER_PULL_ATTEMPTS:-3}"
+timeout_seconds="${OPENCLAW_DOCKER_PULL_TIMEOUT_SECONDS:-480}"
+retry_delay_seconds="${OPENCLAW_DOCKER_PULL_RETRY_DELAY_SECONDS:-20}"
+
+if ! [[ "$attempts" =~ ^[1-9][0-9]*$ ]]; then
+  echo "OPENCLAW_DOCKER_PULL_ATTEMPTS must be a positive integer, got: $attempts" >&2
+  exit 2
+fi
+
+if ! [[ "$timeout_seconds" =~ ^[1-9][0-9]*$ ]]; then
+  echo "OPENCLAW_DOCKER_PULL_TIMEOUT_SECONDS must be a positive integer, got: $timeout_seconds" >&2
+  exit 2
+fi
+
+if ! [[ "$retry_delay_seconds" =~ ^[0-9]+$ ]]; then
+  echo "OPENCLAW_DOCKER_PULL_RETRY_DELAY_SECONDS must be a non-negative integer, got: $retry_delay_seconds" >&2
+  exit 2
+fi
+
+last_status=1
+for attempt in $(seq 1 "$attempts"); do
+  echo "==> Pull Docker image attempt ${attempt}/${attempts}: ${image}"
+  if timeout --foreground --kill-after=30s "${timeout_seconds}s" docker pull "$image"; then
+    exit 0
+  fi
+  last_status="$?"
+  echo "Docker pull failed or timed out after ${timeout_seconds}s: status=${last_status}" >&2
+  if [[ "$attempt" -lt "$attempts" && "$retry_delay_seconds" -gt 0 ]]; then
+    sleep "$retry_delay_seconds"
+  fi
+done
+
+exit "$last_status"