Backend: Python-Logging statt print, Diagnose in allen Fallbacks

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

backend/generator.py

@@ -1,5 +1,6 @@
 import asyncio
 import json
+import logging
 import math
 import shutil
 import subprocess
@@ -45,8 +46,11 @@ def _extra(instructions: str) -> str:
     return f"\n\nZUSÄTZLICHE ANWEISUNGEN VOM NUTZER:\n{instructions}\n" if instructions else ""
 
 
+log = logging.getLogger("creator.generator")
+
+
 def _log(topic: str, msg: str) -> None:
-    print(f"[generator] {topic}: {msg}", flush=True)
+    log.info("[%s] %s", topic, msg)
 
 
 def _claude_error(label: str, returncode: int, stdout: str, stderr: str) -> str:
@@ -112,7 +116,8 @@ def _json_datei(path: Path):
         text = path.read_text(encoding="utf-8").strip()
         text = re.sub(r"^```(?:json)?\s*|\s*```$", "", text)
         return json.loads(text)
-    except Exception:
+    except Exception as e:
+        log.debug("JSON-Datei ungültig: %s (%s)", path, e)
         return None
 
 
@@ -580,6 +585,7 @@ async def generate_bausteine(topic: str, instructions: str = "", provider: str =
                 encoding="utf-8",
             )
     except Exception as e:
+        log.exception("[%s] Bausteine-Generierung fehlgeschlagen", topic)
         _bausteine_errors[topic] = str(e)[:2000]
     finally:
         # Kein Datei-Cleanup: Zwischendateien bleiben für Resume bzw. Nachvollziehbarkeit.
@@ -1317,6 +1323,7 @@ async def generate_guide(guide_id: str, topic: str, format_name: str, instructio
         except FileNotFoundError:
             await _fail(guide_id, "Bausteine fehlen")
         except Exception as e:
+            log.exception("[%s] Guide-Generierung fehlgeschlagen (%s)", topic, guide_id)
             await _fail(guide_id, str(e)[:2000])
         finally:
             _cancelled.discard(guide_id)
@@ -1349,6 +1356,7 @@ async def chat_with_guide(topic: str, format_name: str, section: str, outline: s
         reply = stdout.strip()
         return reply or "Entschuldigung, ich habe keine Antwort erhalten."
     except Exception:
+        log.warning("[%s] Guide-Chat fehlgeschlagen", topic, exc_info=True)
         return "Entschuldigung, das hat nicht geklappt. Bitte versuche es erneut."
 
 
@@ -1432,6 +1440,7 @@ async def generate_element(topic: str, hint: str, provider: str = DEFAULT_PROVID
             return fallback
         return _element_fields(_parse_json_text(stdout)) or fallback
     except Exception:
+        log.warning("[%s] Element-Erstellung fehlgeschlagen", topic, exc_info=True)
         return fallback
 
 
@@ -1488,6 +1497,7 @@ async def check_element(element: dict, provider: str = DEFAULT_PROVIDER) -> list
             return None
         return _parse_suggestions(stdout)
     except Exception:
+        log.warning("[%s] Element-Prüfung fehlgeschlagen", element.get("topic", "?"), exc_info=True)
         return None
 
 
@@ -1545,6 +1555,7 @@ async def chat_with_element(element: dict, messages: list[dict], provider: str =
         reply = str(data.get("reply", "")).strip() or ("Vorschläge erstellt." if changes else fehler)
         return reply, changes
     except Exception:
+        log.warning("[%s] Element-Chat fehlgeschlagen", element.get("topic", "?"), exc_info=True)
         return fehler, []
 
 
@@ -1562,6 +1573,7 @@ async def style_element(element: dict, provider: str = DEFAULT_PROVIDER) -> list
             return None
         return [v for c in data.get("changes", []) if (v := _validate_change(c, element))]
     except Exception:
+        log.warning("[%s] Stil-Prüfung fehlgeschlagen", element.get("topic", "?"), exc_info=True)
         return None
 
 
@@ -1584,4 +1596,5 @@ async def refine_suggestion(element: dict, suggestion: dict, instruction: str, p
             return None
         return _validate_change(data.get("change"), element)
     except Exception:
+        log.warning("[%s] Vorschlags-Überarbeitung fehlgeschlagen", element.get("topic", "?"), exc_info=True)
         return None