feat: add traceback to ScanError (#136)

Author: knielsen404

src/mcp_scan/MCPScanner.py

@@ -2,6 +2,7 @@
 import logging
 import os
 import re
+import traceback
 from collections import defaultdict
 from collections.abc import Callable
 from typing import Any
@@ -150,11 +151,11 @@ async def get_servers_from_path(self, path: str) -> ScanPathResult:
             error_msg = f"resource {path} not found" if is_direct_scan(path) else f"file {path} does not exist"
             logger.exception("%s: %s", error_msg, path)
             # This is a non failing error, so we set is_failure to False.
-            result.error = ScanError(message=error_msg, exception=e, is_failure=False)
+            result.error = ScanError(message=error_msg, exception=e, traceback=traceback.format_exc(), is_failure=False)
         except Exception as e:
             error_msg = f"could not scan {path}" if is_direct_scan(path) else f"could not parse file {path}"
             logger.exception("%s: %s", error_msg, path)
-            result.error = ScanError(message=error_msg, exception=e, is_failure=True)
+            result.error = ScanError(message=error_msg, exception=e, traceback=traceback.format_exc(), is_failure=True)
         return result
 
     def check_server_changed(self, path_result: ScanPathResult) -> list[Issue]:
@@ -217,11 +218,11 @@ async def scan_server(self, server: ServerScanResult) -> ServerScanResult:
         except HTTPStatusError as e:
             error_msg = "server returned HTTP status code"
             logger.exception("%s: %s", error_msg, server.name)
-            result.error = ScanError(message=error_msg, exception=e, is_failure=True)
+            result.error = ScanError(message=error_msg, exception=e, traceback=traceback.format_exc(), is_failure=True)
         except Exception as e:
             error_msg = "could not start server"
             logger.exception("%s: %s", error_msg, server.name)
-            result.error = ScanError(message=error_msg, exception=e, is_failure=True)
+            result.error = ScanError(message=error_msg, exception=e, traceback=traceback.format_exc(), is_failure=True)
         await self.emit("server_scanned", result)
         return result
 

src/mcp_scan/models.py

@@ -184,6 +184,7 @@ class ScanError(BaseModel):
     model_config = ConfigDict(arbitrary_types_allowed=True)
     message: str | None = None
     exception: Exception | str | None = None
+    traceback: str | None = None
     is_failure: bool = True
 
     @field_serializer("exception")
@@ -202,6 +203,7 @@ def clone(self) -> "ScanError":
         return ScanError(
             message=self.message,
             exception=self.exception,
+            traceback=self.traceback,
             is_failure=self.is_failure,
         )
 

src/mcp_scan/verify_api.py

@@ -3,6 +3,7 @@
 import logging
 import os
 import ssl
+import traceback
 
 import aiohttp
 import certifi
@@ -215,7 +216,9 @@ async def analyze_machine(
                 logger.warning(error_text)
                 for scan_path in scan_paths:
                     if scan_path.servers is not None and scan_path.error is None:
-                        scan_path.error = ScanError(message=error_text, exception=e, is_failure=True)
+                        scan_path.error = ScanError(
+                            message=error_text, exception=e, traceback=traceback.format_exc(), is_failure=True
+                        )
                 return scan_paths
 
         except RuntimeError as e:
@@ -240,6 +243,7 @@ async def analyze_machine(
             scan_path.error = ScanError(
                 message=f"Tried calling verification api {max_retries} times. Could not reach analysis server. Last error: {error_text}",
                 exception=None,
+                traceback=traceback.format_exc(),
                 is_failure=True,
             )
     return scan_paths

tests/unit/test_control_server.py

@@ -158,10 +158,13 @@ async def test_upload_includes_scan_error_in_payload():
     server = ServerScanResult(name="server1", server=StdioServer(command="echo"))
     scan_error_message = "something went wrong"
     exception_message = "could not start server"
+    traceback = "traceback"
     path_result_with_error = ScanPathResult(
         path="/test/path",
         servers=[server],
-        error=ScanError(message=scan_error_message, exception=Exception(exception_message), is_failure=True),
+        error=ScanError(
+            message=scan_error_message, exception=Exception(exception_message), traceback=traceback, is_failure=True
+        ),
     )
 
     with patch("mcp_scan.upload.get_user_info") as mock_get_user_info:
@@ -199,6 +202,7 @@ async def test_upload_includes_scan_error_in_payload():
             assert scan_error_message in sent_result["error"].get("message")
             assert exception_message in sent_result["error"].get("exception")
             assert sent_result["error"]["is_failure"] is True
+            assert sent_result["error"]["traceback"] == traceback
 
 
 @pytest.mark.asyncio