Experimental placeholder video functionality

app.py

@@ -3,8 +3,9 @@ import http.cookiejar
 import json
 import requests
 from bs4 import BeautifulSoup
-from flask import Flask, Response, request, jsonify
+from flask import Flask, Response, request, jsonify, send_file, make_response
 from diskcache import Cache
+from io import BytesIO
 import logging
 
 import threading
@@ -36,6 +37,17 @@ CACHE_EXPIRATION_HTML = 60 * 60  # 1 hour
 CACHE_EXPIRATION_CDN = 60 * 60 * 24 * 7  # 1 week
 CACHE_SIZE_LIMIT = 100 * 1024 * 1024  # 100 MB
 
+placeholder_video = None
+PLACEHOLDER_VIDEO_PATH = os.environ.get('NICONICOGAY_PLACEHOLDER_VIDEO', 'placeholder.mp4')
+try:
+    with open(PLACEHOLDER_VIDEO_PATH, 'rb') as f:
+        placeholder_video = BytesIO(f.read())
+    logger.debug("Loaded placeholder video")
+except FileNotFoundError:
+    logger.warning(f"Placeholder video file '{PLACEHOLDER_VIDEO_PATH}' not found")
+except Exception as e:
+    logger.error(f"Error loading placeholder video: {e}")
+
 cache = None
 if os.environ.get('NICONICOGAY_DISABLE_CACHE', '') != '1':
     cache = Cache("disk_cache", size_limit=CACHE_SIZE_LIMIT)
@@ -273,6 +285,29 @@ def get_oembed_url(params):
     return oembed_url
 
 
+@app.route("/cdn/<video_id>.mp4")
+def cdn_redirect(video_id):
+    """
+    Checks if a video exists in CDN and redirects accordingly.
+    Returns CDN URL if video exists, otherwise returns a placeholder video URL.
+    Only responds to requests from Discord bots.
+    """
+    logger.info(f"{video_id}: CDN redirect request received")
+    request_user_agent = request.headers.get('User-Agent', '').lower()
+    if 'discordbot' not in request_user_agent:
+        logger.info(f"{video_id}: Video CDN redirect ignored due to user agent ({request_user_agent})")
+        return Response("Video not found", status=404)
+
+    if placeholder_video is None or is_video_in_cdn(video_id):
+        cdn_url = get_cdn_url(video_id)
+        logger.info(f"{video_id}: Redirecting to CDN URL: {cdn_url}")
+        return Response("", status=302, headers={"Location": cdn_url})
+
+    logger.info(f"{video_id}: Video not found in CDN, returning placeholder")
+    response = make_response(send_file(placeholder_video, mimetype="video/mp4"))
+    response.headers['Content-Length'] = str(placeholder_video.getbuffer().nbytes)
+    return response
+
 
 @app.route("/watch/<video_id>")
 def proxy(video_id):
@@ -329,7 +364,7 @@ def proxy(video_id):
                     download_queue.append((video_id, real_url, video_quality))
                     logger.info(f"{video_id}: Queued for download")
 
-    cdn_video_url = get_cdn_url(video_id)
+    cdn_video_url = f"{HOST}/cdn/{video_id}.mp4" if placeholder_video else get_cdn_url(video_id)
     og_tags = soup.find_all("meta", attrs={"property": True})
     for tag in og_tags:
         # Remove attribute(s) added by niconico
@@ -372,6 +407,7 @@ if you want to download videos, please consider using a tool like nndownload: ht
     logger.info(f"{video_id}: Returning response")
     return Response(html_response, mimetype="text/html")
 
+
 @app.route("/owoembed")
 def owoembed():
     """