finish implementing torrent verb

endpoints/verbs.py

@@ -6,6 +6,7 @@ from flask import redirect, Blueprint, abort, send_file, make_response
 
 from app import app, signer, storage
 from auth.auth import process_auth
+from auth.auth_context import get_authenticated_user
 from auth.permissions import ReadRepositoryPermission
 from data import model, database
 from endpoints.trackhelper import track_and_log
@@ -14,9 +15,10 @@ from storage import Storage
 
 from util.registry.queuefile import QueueFile
 from util.registry.queueprocess import QueueProcess
+from util.registry.torrent import make_torrent, private_torrent_name
 from formats.squashed import SquashedDockerImage
 from formats.aci import ACIImage
-from endpoints.v2.blob import BASE_BLOB_ROUTE, blob_fetch
+from endpoints.v2.blob import BLOB_DIGEST_ROUTE
 
 
 verbs = Blueprint('verbs', __name__)
@@ -278,13 +280,17 @@ def get_squashed_tag(namespace, repository, tag):
 
 
 @anon_protect
-@verbs.route('/torrent'+BASE_BLOB_ROUTE, methods=['GET'])
+@verbs.route('/torrent{0}'.format(BLOB_DIGEST_ROUTE), methods=['GET'])
 @process_auth
 def get_tag_torrent(namespace, repository, digest):
   permission = ReadRepositoryPermission(namespace, repository)
   if not permission.can() and not model.repository.repository_is_public(namespace, repository):
     abort(403)
 
+  user = get_authenticated_user()
+  if user is None:
+    abort(403)
+
   try:
     blob = model.blob.get_repo_blob_by_digest(namespace, repository, digest)
   except model.BlobDoesNotExist:
@@ -296,10 +302,17 @@ def get_tag_torrent(namespace, repository, digest):
     # We cannot support webseeds for storages that cannot provide direct downloads.
     abort(501)
 
+  try:
     torrent_info = model.storage.get_torrent_info(blob)
-  torrent_file = make_torrent(namespace, repository, digest, webseed,
+  except model.TorrentInfoDoesNotExist:
+    abort(404)
+
+  name = private_torrent_name(user.uuid, blob.uuid)
+  torrent_file = make_torrent(name, webseed, blob.image_size,
                               torrent_info.piece_length, torrent_info.pieces)
 
-  torrent_file = None
+  headers = {'Content-Type': 'application/x-bittorrent',
-  return make_response((torrent_file, 200, {'Content-Type': 'application/x-bittorrent',
+             'Content-Disposition': 'attachment; filename={0}.torrent'.format(name),
-                                            'Content-Length': len(torrent_file)}))
+             'Content-Length': len(torrent_file)}
+
+  return make_response((torrent_file, 200, headers))

util/registry/torrent.py

@@ -1,5 +1,34 @@
+import time
+import hashlib
+
+import bencode
 import resumablehashlib
 
+from app import app
+
+
+TRACKER_ANNOUNCE_URL = app.config.get('BT_TRACKER_ANNOUNCE_URL')
+NAMING_SALT = app.config.get('BT_NAMING_SALT')
+
+def private_torrent_name(user_uuid, blob_uuid):
+  return hashlib.sha256(blob_uuid + user_uuid + NAMING_SALT).hexdigest()
+
+
+def make_torrent(name, webseed, length, piece_length, pieces):
+  return bencode.bencode({
+    'announce': TRACKER_ANNOUNCE_URL,
+    'url-list': webseed,
+    'encoding': 'UTF-8',
+    'created by': 'Quay Container Registry',
+    'creation date': int(time.time()),
+    'info': {
+      'name': name,
+      'length': length,
+      'piece length': piece_length,
+      'pieces': pieces,
+    },
+  })
+
 
 class PieceHasher(object):
   def __init__(self, piece_size, starting_offset, starting_piece_hash_bytes, hash_fragment_to_resume):