Task results: upload allegati per MeasurementTec, percorsi in task_results/, test e migrazione 018 (#55 #53 #54)

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

src/backend/api/routers/files.py

@@ -61,7 +61,8 @@ def detect_file_type(content: bytes) -> tuple[str, str] | None:
 
 # Top-level folders nothing may DELETE through this router: statistics/reports are
 # audit records, the logo is only ever replaced via POST /api/settings/logo.
-_UNDELETABLE_PREFIXES = ("statistics/", "reports/", "logos/")
+# task_results/: allegati degli esiti dei task (#55), record di audit.
+_UNDELETABLE_PREFIXES = ("statistics/", "reports/", "logos/", "task_results/")
 
 # GET under these needs a role that is meant to see production data, not just
 # any authenticated user (a Maker or MeasurementTec has no business reading

src/backend/api/routers/task_results.py

@@ -4,13 +4,20 @@ Un 'check' registra ok o nok (nok vuole la nota); un 'note' registra 'done' con
 valori dei campi extra e gli allegati. I task di misura non passano di qui: le
 loro letture sono Measurement.
 """
+import uuid
+from datetime import datetime, timezone
+from pathlib import Path
 from typing import Optional
 
-from fastapi import APIRouter, Depends, HTTPException, Query, status
+from fastapi import APIRouter, Depends, File, HTTPException, Query, UploadFile, status
 from sqlalchemy import select
 from sqlalchemy.ext.asyncio import AsyncSession
 
 from src.backend.api.middleware.api_key import require_measurement_tec
+from src.backend.api.routers.files import (
+    _UPLOAD_CHUNK_SIZE, detect_file_type, sanitize_filename,
+)
+from src.backend.config import settings
 from src.backend.database import get_db
 from src.backend.models.api.task_result import TaskResultCreate, TaskResultResponse
 from src.backend.models.orm.production import ProductionRun
@@ -26,11 +33,62 @@ def _unprocessable(detail: str) -> HTTPException:
     return HTTPException(status_code=status.HTTP_422_UNPROCESSABLE_ENTITY, detail=detail)
 
 
+# Radice degli allegati degli esiti: sotto upload_path, mai cancellabile (audit).
+ATTACHMENT_DIR = "task_results"
+
+
 def _safe_relative_path(path: str) -> bool:
-    """Percorso di upload: relativo, senza '..', senza unita' o backslash."""
+    """Allegato: relativo, dentro task_results/, senza '..', unita' o backslash."""
     if path.startswith("/") or "\\" in path or ":" in path:
         return False
-    return ".." not in path.split("/")
+    parts = path.split("/")
+    return ".." not in parts and parts[0] == ATTACHMENT_DIR and len(parts) > 1
+
+
+@router.post("/attachments", status_code=status.HTTP_201_CREATED)
+async def upload_attachment(
+    file: UploadFile = File(...),
+    _user: User = Depends(require_measurement_tec),
+):
+    """Carica l'allegato di un task 'note' (l'operatore non ha accesso a /api/files/upload).
+
+    Stessi controlli di upload_file: tipo dai magic bytes, limite di dimensione
+    con lettura a blocchi, nome ripulito. Salva sotto task_results/<AAAA>/<MM>/.
+    """
+    max_bytes = settings.max_upload_size_mb * 1024 * 1024
+    buffer = bytearray()
+    while True:
+        chunk = await file.read(_UPLOAD_CHUNK_SIZE)
+        if not chunk:
+            break
+        buffer.extend(chunk)
+        if len(buffer) > max_bytes:
+            raise HTTPException(
+                status_code=status.HTTP_400_BAD_REQUEST,
+                detail=f"File size exceeds maximum {settings.max_upload_size_mb}MB",
+            )
+    content = bytes(buffer)
+
+    detected = detect_file_type(content)
+    if detected is None:
+        raise HTTPException(
+            status_code=status.HTTP_400_BAD_REQUEST,
+            detail="File type not allowed. Must be a recognised image or PDF.",
+        )
+    _mime, ext = detected
+
+    # nome originale ripulito (per mostrarlo); sul disco solo uuid + estensione rilevata
+    name = sanitize_filename(file.filename or "")
+    now = datetime.now(timezone.utc)
+    storage_dir = settings.upload_path / ATTACHMENT_DIR / f"{now:%Y}" / f"{now:%m}"
+    storage_dir.mkdir(parents=True, exist_ok=True)
+    target = storage_dir / f"{uuid.uuid4().hex}{ext}"
+    target.write_bytes(content)
+
+    return {
+        "file_path": str(target.relative_to(settings.upload_path)).replace("\\", "/"),
+        "name": name,
+    }
 
 
 @router.post("", response_model=TaskResultResponse, status_code=status.HTTP_201_CREATED)
@@ -73,7 +131,9 @@ async def create_task_result(
         attachments = []
         for att in data.attachments or []:
             if not _safe_relative_path(att.path):
-                raise _unprocessable(f"Percorso allegato non valido: {att.path}")
+                raise _unprocessable(
+                    f"Percorso allegato non valido (deve stare in {ATTACHMENT_DIR}/): {att.path}"
+                )
             if att.key is not None and att.key not in fields:
                 raise _unprocessable(f"Campo allegato '{att.key}' non previsto dal task")
             attachments.append(att.model_dump())