Build Flask WAF log converter app

app/services/storage.py

@@ -0,0 +1,43 @@
+import json
+import uuid
+from dataclasses import asdict, dataclass
+from pathlib import Path
+
+from app.services.exporter import ExportResult
+
+
+@dataclass(slots=True)
+class ResultMetadata:
+    result_id: str
+    file_path: str
+    download_name: str
+    mimetype: str
+
+
+def persist_result(output_dir: Path, export_result: ExportResult) -> ResultMetadata:
+    """Persist generated output and sidecar metadata in a temporary directory."""
+    result_id = uuid.uuid4().hex
+    extension = "txt" if export_result.output_format == "text" else "csv"
+    mimetype = "text/plain; charset=utf-8" if extension == "txt" else "text/csv; charset=utf-8"
+
+    file_path = output_dir / f"{result_id}.{extension}"
+    metadata_path = output_dir / f"{result_id}.json"
+
+    file_path.write_text(export_result.content, encoding="utf-8")
+    metadata = ResultMetadata(
+        result_id=result_id,
+        file_path=str(file_path),
+        download_name=f"waf-report.{extension}",
+        mimetype=mimetype,
+    )
+    metadata_path.write_text(json.dumps(asdict(metadata)), encoding="utf-8")
+    return metadata
+
+
+def load_result_metadata(output_dir: Path, result_id: str) -> dict[str, str] | None:
+    """Load sidecar metadata for a generated file."""
+    metadata_path = output_dir / f"{result_id}.json"
+    if not metadata_path.exists():
+        return None
+
+    return json.loads(metadata_path.read_text(encoding="utf-8"))