feat: initial commit

backend/app/services/render_log.py

@@ -0,0 +1,72 @@
+"""Redis-backed live render log for streaming task progress.
+
+Each order line gets a Redis list keyed by render:log:{order_line_id}.
+Entries are JSON objects with timestamp, level, and message.
+Lists auto-expire after 1 hour.
+"""
+import json
+import time
+import logging
+
+import redis
+
+from app.config import settings
+
+logger = logging.getLogger(__name__)
+
+_LOG_TTL = 3600  # 1 hour
+_MAX_ENTRIES = 500
+
+
+def _redis() -> redis.Redis:
+    return redis.from_url(settings.redis_url, decode_responses=True)
+
+
+def _key(order_line_id: str) -> str:
+    return f"render:log:{order_line_id}"
+
+
+def emit(order_line_id: str, message: str, level: str = "info") -> None:
+    """Push a log entry for a render job."""
+    entry = json.dumps({
+        "ts": time.time(),
+        "t": time.strftime("%H:%M:%S", time.gmtime()),
+        "level": level,
+        "msg": message,
+    })
+    try:
+        r = _redis()
+        key = _key(order_line_id)
+        r.rpush(key, entry)
+        r.ltrim(key, -_MAX_ENTRIES, -1)
+        r.expire(key, _LOG_TTL)
+    except Exception as exc:
+        logger.debug(f"render_log emit failed: {exc}")
+
+
+def get_entries(order_line_id: str, after_index: int = 0) -> list[dict]:
+    """Get log entries starting from after_index."""
+    try:
+        r = _redis()
+        raw = r.lrange(_key(order_line_id), after_index, -1)
+        return [json.loads(e) for e in raw]
+    except Exception:
+        return []
+
+
+def count(order_line_id: str) -> int:
+    """Get the number of log entries."""
+    try:
+        r = _redis()
+        return r.llen(_key(order_line_id))
+    except Exception:
+        return 0
+
+
+def clear(order_line_id: str) -> None:
+    """Clear log entries for a render job."""
+    try:
+        r = _redis()
+        r.delete(_key(order_line_id))
+    except Exception:
+        pass