Add admin database backup export and import

app/routers/admin.py

@@ -2,12 +2,14 @@ from __future__ import annotations
 
 import secrets
 from datetime import datetime, timezone
+from urllib.parse import quote, unquote
 
-from fastapi import APIRouter, Depends, Form, HTTPException, Request
-from fastapi.responses import HTMLResponse, RedirectResponse
+from fastapi import APIRouter, Depends, File, Form, HTTPException, Request, UploadFile
+from fastapi.responses import HTMLResponse, RedirectResponse, Response
 from fastapi.templating import Jinja2Templates
 
 from auth import check_admin_credentials, get_current_admin, require_admin_page
+from backup import dumps_backup, export_backup, import_backup, loads_backup
 from config import get_settings
 from database import get_db
 from urlutil import public_base_url
@@ -121,6 +123,10 @@ async def admin_dashboard(request: Request):
         page = total_pages
 
     site_base = public_base_url(request)
+    flash = request.query_params.get("flash")
+    flash_error = request.query_params.get("flash_error")
+    if flash_error:
+        flash_error = unquote(flash_error)
     return templates.TemplateResponse(
         "admin/dashboard.html",
         {
@@ -128,7 +134,8 @@ async def admin_dashboard(request: Request):
             "brand": settings.brand_name,
             "links": links,
             "site_base": site_base,
-            "flash": request.query_params.get("flash"),
+            "flash": flash,
+            "flash_error": flash_error,
             "tab": tab,
             "page": page,
             "per_page": per_page,
@@ -293,3 +300,47 @@ async def link_detail(request: Request, link_id: int):
             "site_base": public_base_url(request),
         },
     )
+
+
+@router.get("/backup/export")
+async def backup_export(_admin: str = Depends(get_current_admin)):
+    payload = await export_backup()
+    stamp = datetime.now(timezone.utc).strftime("%Y%m%d-%H%M%S")
+    filename = f"remna-backup-{stamp}.json"
+    return Response(
+        content=dumps_backup(payload),
+        media_type="application/json; charset=utf-8",
+        headers={"Content-Disposition": f'attachment; filename="{filename}"'},
+    )
+
+
+@router.post("/backup/import")
+async def backup_import(
+    file: UploadFile = File(...),
+    _admin: str = Depends(get_current_admin),
+):
+    raw = await file.read()
+    if not raw:
+        return RedirectResponse(
+            "/admin?type=all&flash_error=" + quote("пустой файл"),
+            status_code=303,
+        )
+    if len(raw) > 20 * 1024 * 1024:
+        return RedirectResponse(
+            "/admin?type=all&flash_error=" + quote("файл слишком большой (макс 20 МБ)"),
+            status_code=303,
+        )
+    try:
+        data = loads_backup(raw)
+        await import_backup(data)
+    except ValueError as exc:
+        return RedirectResponse(
+            "/admin?type=all&flash_error=" + quote(str(exc)[:200]),
+            status_code=303,
+        )
+    except Exception as exc:
+        return RedirectResponse(
+            "/admin?type=all&flash_error=" + quote(str(exc)[:200]),
+            status_code=303,
+        )
+    return RedirectResponse("/admin?type=all&flash=imported", status_code=303)