fix: serve admin media previews from telegram

src/vk_parser_app/admin.py

@@ -9,14 +9,18 @@ import re
 import secrets
 import time
 from datetime import date, datetime, timedelta, timezone
+from io import BytesIO
 from pathlib import Path
 from typing import Any
 from urllib.parse import urlencode
 from zoneinfo import ZoneInfo
 
 import aiohttp
+from aiogram import Bot
+from aiogram.client.session.aiohttp import AiohttpSession
+from aiogram.client.telegram import TelegramAPIServer
 from fastapi import FastAPI, File, Form, HTTPException, Request, UploadFile, status
-from fastapi.responses import FileResponse, HTMLResponse, JSONResponse, RedirectResponse
+from fastapi.responses import FileResponse, HTMLResponse, JSONResponse, RedirectResponse, Response
 from fastapi.staticfiles import StaticFiles
 from fastapi.templating import Jinja2Templates
 from loguru import logger
@@ -502,6 +506,40 @@ async def get_current_user(request: Request) -> dict | None:
     return dict(row) if row else None
 
 
+@app.get("/raw/media/{media_id}")
+async def raw_media_preview(request: Request, media_id: int) -> Response:
+    if not await get_current_user(request):
+        raise HTTPException(status_code=status.HTTP_401_UNAUTHORIZED)
+    pool = await get_pool()
+    media = await pool.fetchrow(
+        "SELECT media_type, tg_file_id FROM raw_post_media WHERE id=$1",
+        media_id,
+    )
+    if not media or media["media_type"] != "photo" or not media["tg_file_id"]:
+        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND)
+
+    local_bot_api_url = str(await fetch_setting("local_bot_api_url", settings.local_bot_api_url) or "").strip()
+    session = (
+        AiohttpSession(api=TelegramAPIServer.from_base(local_bot_api_url.rstrip("/"), is_local=True))
+        if local_bot_api_url
+        else AiohttpSession()
+    )
+    bot = Bot(token=settings.tg_bot_token, session=session)
+    output = BytesIO()
+    try:
+        await bot.download(str(media["tg_file_id"]), destination=output)
+    except Exception as exc:
+        logger.warning("Telegram media preview failed for media {}: {}", media_id, exc)
+        raise HTTPException(status_code=status.HTTP_502_BAD_GATEWAY, detail="Media preview unavailable") from exc
+    finally:
+        await bot.session.close()
+    return Response(
+        content=output.getvalue(),
+        media_type="image/jpeg",
+        headers={"Cache-Control": "private, max-age=3600"},
+    )
+
+
 def require_csrf(user: dict, csrf_token: str) -> None:
     if not user or csrf_token != user["csrf_token"]:
         raise PermissionError("bad csrf")
@@ -2680,7 +2718,11 @@ async def raw_posts(
                    jsonb_build_object(
                      'id', rpm.id,
                      'type', rpm.media_type,
-                     'url', rpm.original_url,
+                     'url', CASE
+                       WHEN rpm.media_type='photo' AND rpm.tg_file_id IS NOT NULL
+                         THEN '/raw/media/' || rpm.id::text
+                       ELSE rpm.original_url
+                     END,
                      'status', rpm.status,
                      'error', rpm.error,
                      'duration_sec', rpm.duration_sec
@@ -2846,7 +2888,11 @@ async def fetch_single_editor_row(pool, post_id: int):
                    jsonb_build_object(
                      'id', rpm.id,
                      'type', rpm.media_type,
-                     'url', rpm.original_url,
+                     'url', CASE
+                       WHEN rpm.media_type='photo' AND rpm.tg_file_id IS NOT NULL
+                         THEN '/raw/media/' || rpm.id::text
+                       ELSE rpm.original_url
+                     END,
                      'status', rpm.status,
                      'error', rpm.error,
                      'duration_sec', rpm.duration_sec
@@ -2987,7 +3033,11 @@ async def editor_feed(
                    jsonb_build_object(
                      'id', rpm.id,
                      'type', rpm.media_type,
-                     'url', rpm.original_url,
+                     'url', CASE
+                       WHEN rpm.media_type='photo' AND rpm.tg_file_id IS NOT NULL
+                         THEN '/raw/media/' || rpm.id::text
+                       ELSE rpm.original_url
+                     END,
                      'status', rpm.status,
                      'error', rpm.error,
                      'duration_sec', rpm.duration_sec
@@ -3327,7 +3377,11 @@ async def raw_post_detail(request: Request, post_id: int):
                    jsonb_build_object(
                      'id', rpm.id,
                      'type', rpm.media_type,
-                     'url', rpm.original_url,
+                     'url', CASE
+                       WHEN rpm.media_type='photo' AND rpm.tg_file_id IS NOT NULL
+                         THEN '/raw/media/' || rpm.id::text
+                       ELSE rpm.original_url
+                     END,
                      'status', rpm.status,
                      'error', rpm.error,
                      'duration_sec', rpm.duration_sec