feat(backend): add FastAPI backend — procurement, inventory domain, Casdoor auth, PM arrival endpoints

backend/app/main.py

@@ -0,0 +1,167 @@
+"""FastAPI application assembly.
+
+- Routes: all routers under /api/v1
+- Errors: contract envelope {"error": {"code", "message", "field"}}
+- Lifespan: ensure units-dashboard tables (IF NOT EXISTS) + background
+  auto-expiry scheduler for offered quotes past their expiry_date.
+"""
+import asyncio
+import logging
+from contextlib import asynccontextmanager
+
+from fastapi import FastAPI, Request
+from fastapi.exceptions import RequestValidationError
+from fastapi.middleware.cors import CORSMiddleware
+from fastapi.responses import JSONResponse
+from sqlalchemy.exc import IntegrityError
+
+from app.config import settings
+from app.db.engine import AsyncSessionLocal, engine
+from app.db.init_db import (
+    ensure_attachment_table,
+    ensure_dashboard_tables,
+    ensure_material_topic_column,
+    ensure_quote_projects,
+    ensure_v26,
+)
+from app.routers import ROUTERS
+from app.services.quote_service import auto_expire_quotes
+from app.utils.errors import AppError
+
+logging.basicConfig(level=logging.INFO, format="%(asctime)s %(levelname)s %(name)s — %(message)s")
+logger = logging.getLogger("procurement")
+
+API_V1_PREFIX = "/api/v1"
+
+
+async def _auto_expire_loop() -> None:
+    """Background job: expire quotes with expiry_date < today AND status='offered'."""
+    while True:
+        await asyncio.sleep(settings.AUTO_EXPIRE_INTERVAL_SECONDS)
+        try:
+            async with AsyncSessionLocal() as session:
+                await auto_expire_quotes(session)
+        except Exception:
+            logger.exception("Auto-expiry pass failed")
+
+
+@asynccontextmanager
+async def lifespan(_app: FastAPI):
+    await ensure_dashboard_tables(engine)
+    await ensure_attachment_table(engine)
+    await ensure_material_topic_column(engine)
+    await ensure_quote_projects(engine)
+    await ensure_v26(engine)
+    task = asyncio.create_task(_auto_expire_loop()) if settings.AUTO_EXPIRE_ENABLED else None
+    try:
+        yield
+    finally:
+        if task is not None:
+            task.cancel()
+            try:
+                await task
+            except asyncio.CancelledError:
+                pass
+        await engine.dispose()
+
+
+app = FastAPI(
+    title="Procurement API",
+    version="2.4.0",
+    description="Backend for the procurement system — schema v2.4 (expert-opinion contracts P0/P1/P2)",
+    lifespan=lifespan,
+)
+
+app.add_middleware(
+    CORSMiddleware,
+    allow_origins=settings.CORS_ORIGINS,
+    allow_credentials=True,
+    allow_methods=["*"],
+    allow_headers=["*"],
+)
+
+
+# ---------------------------------------------------------------------------
+# Exception handlers — contract error envelope
+# ---------------------------------------------------------------------------
+
+@app.exception_handler(AppError)
+async def app_error_handler(_request: Request, exc: AppError):
+    return JSONResponse(status_code=exc.status_code, content=exc.body)
+
+
+# ترجمه‌ی پیام‌های اعتبارسنجی pydantic به فارسی — الگوهای رایج
+_VALIDATION_FA: list[tuple[str, str]] = [
+    ("field required", "فیلد الزامی خالی است"),
+    ("input should be a valid uuid", "شناسه‌ی ارسال‌شده معتبر نیست"),
+    ("input should be a valid datetime", "تاریخ و ساعت واردشده معتبر نیست"),
+    ("input should be a valid date", "تاریخ واردشده معتبر نیست"),
+    ("input should be a valid integer", "عدد صحیح وارد کنید"),
+    ("input should be a valid number", "عدد معتبر وارد کنید"),
+    ("input should be a valid boolean", "مقدار درست/نادرست (بولی) وارد کنید"),
+    ("input should be greater than 0", "مقدار باید بزرگ‌تر از صفر باشد"),
+    ("input should be greater than or equal to", "مقدار از حداقل مجاز کوچک‌تر است"),
+    ("input should be less than or equal to", "مقدار از حداکثر مجاز بزرگ‌تر است"),
+    ("string should have at least 1 character", "متن نباید خالی باشد"),
+    ("string too short", "مقدار خیلی کوتاه است"),
+    ("string too long", "مقدار خیلی طولانی است"),
+    ("value error", "مقدار واردشده نامعتبر است"),
+]
+
+
+def _fa_validation_msg(msg: str) -> str:
+    lower = msg.lower()
+    for en, fa in _VALIDATION_FA:
+        if en in lower:
+            return fa
+    return msg
+
+
+@app.exception_handler(RequestValidationError)
+async def validation_error_handler(_request: Request, exc: RequestValidationError):
+    first = exc.errors()[0]
+    loc = [str(part) for part in first.get("loc", []) if part not in ("body", "query", "path")]
+    field = ".".join(loc) if loc else None
+    return JSONResponse(
+        status_code=400,
+        content={
+            "error": {
+                "code": "VALIDATION_ERROR",
+                "message": _fa_validation_msg(first.get("msg", "داده نامعتبر است")),
+                "field": field,
+            }
+        },
+    )
+
+
+@app.exception_handler(IntegrityError)
+async def integrity_error_handler(_request: Request, exc: IntegrityError):
+    # Services pre-check FKs and duplicates, so an IntegrityError here almost
+    # always means a unique-constraint violation → 409 CONFLICT.
+    logger.warning("IntegrityError: %s", exc.orig)
+    return JSONResponse(
+        status_code=409,
+        content={"error": {"code": "CONFLICT", "message": "تعارض داده — رکورد تکراری یا ارجاع نامعتبر"}},
+    )
+
+
+@app.exception_handler(Exception)
+async def unhandled_error_handler(_request: Request, exc: Exception):
+    logger.exception("Unhandled error: %s", exc)
+    return JSONResponse(
+        status_code=500,
+        content={"error": {"code": "INTERNAL_ERROR", "message": "خطای داخلی سرور"}},
+    )
+
+
+# ---------------------------------------------------------------------------
+# Routes
+# ---------------------------------------------------------------------------
+
+for router in ROUTERS:
+    app.include_router(router, prefix=API_V1_PREFIX)
+
+
+@app.get("/health", tags=["system"])
+async def health():
+    return {"status": "ok", "service": "procurement-api"}