app/proxy/__init__.py

   1 import re
   2 import requests, requests_cache
   3 from flask import Flask, Blueprint, request, Response, g
   4 from flask_login import current_user
   5 from werkzeug.exceptions import Forbidden
   6
   7 from ..common.common import cf
   8
   9 frontend = Blueprint('proxy', __name__)
  10
  11 def app():
  12     app = Flask(__name__)
  13     app.register_blueprint(frontend)
  14     return app
  15
  16 # https://github.com/psf/requests/issues/5612
  17 def silence_errors(generator):
  18     try:
  19          yield from generator
  20     except requests.exceptions.RequestException:
  21          return None
  22
  23 @frontend.route("/videoplayback/<path:path>")
  24 @frontend.route("/videoplayback")
  25 def videoplayback(path=None):
  26     if path is not None:  # seg.ts URL
  27         args = path.split("/")[0:-1]
  28         host = dict(zip(args[::2], args[1::2])).get('hls_chunk_host')
  29         path = "/" + path.replace(';','%3B').replace('=','%3D')
  30     else:
  31         fvip = request.args.get("fvip", "3")
  32         mn = request.args.get("mn", "").split(",")[-1]
  33         host = f"r{fvip}---{mn}.googlevideo.com"
  34         path = ""
  35
  36     REQUEST_HEADERS_WHITELIST  = {
  37         "accept",
  38         "accept-encoding",
  39         "cache-control",
  40         "range",
  41     }
  42     RESPONSE_HEADERS_WHITELIST = {
  43         "accept-ranges",
  44         "cache-control",
  45         "content-length",
  46         "content-range",
  47         "content-type",
  48         "expires",
  49         "x-content-type-options",
  50     }
  51
  52     req_headers = {
  53         k:v for k,v in request.headers
  54         if k.lower() in REQUEST_HEADERS_WHITELIST
  55     }
  56     with requests_cache.disabled():
  57       try:
  58         r = requests.get(f"https://{host}/videoplayback{path}",
  59             request.args.to_dict(),
  60             headers=req_headers,
  61             stream=True)
  62       except requests.exceptions.ConnectionError:
  63         return f"unable to connect to {host}", 502
  64
  65     resp_headers = {
  66         k:v for k,v in r.headers.items()
  67         if k.lower() in RESPONSE_HEADERS_WHITELIST
  68     }
  69     response = Response(
  70         silence_errors(r.iter_content(chunk_size=8192)),
  71         status=r.status_code, headers=resp_headers)
  72     response.call_on_close(lambda: r.close())
  73     response.headers['Access-Control-Allow-Origin'] = cors_origin()
  74     return response
  75
  76 @frontend.route("/api/manifest/hls_playlist/<path:path>")
  77 @frontend.route("/api/manifest/hls_variant/<path:path>")
  78 def hls_manifest(path):
  79     path_fixed = request.path.replace(';','%3B').replace('=','%3D')
  80     with requests_cache.disabled():
  81         r = requests.get(f"https://manifest.googlevideo.com{path_fixed}")
  82     if not r.ok:
  83         return "", r.status_code
  84
  85     rv = re.sub(r"^https://[a-z0-9-]+\.googlevideo\.com", "", r.text, flags=re.M)
  86     if "/api/manifest/hls_variant" in request.path:
  87         rv = rv + "\n#EXT-X-ENDLIST"
  88     return rv, {
  89         'Content-Type': 'application/x-mpegURL',
  90         'Access-Control-Allow-Origin': cors_origin()
  91     }
  92
  93 def cors_origin():
  94     return f"{request.environ.get('wsgi.url_scheme')}://{request.host}"
  95
  96 def proxy_allowed():
  97     """ the proxy can be restricted to logged-in users by a config flag """
  98     require_auth = cf.getboolean('proxy', 'require_auth', fallback=False)
  99     is_authd = not current_user.is_anonymous
 100     return is_authd or not require_auth
 101
 102 @frontend.before_request
 103 def check_auth():
 104     if not proxy_allowed():
 105         raise Forbidden("limited to authenticated users")
 106
 107 @frontend.before_app_request
 108 def propagate_auth_requirement():
 109     g.proxy_on = proxy_allowed()
 110
 111
 112 if __name__ == '__main__':
 113     app().run(debug=True)