2 from binascii import b2a_hex
3 from urlparse import urlunparse
6 from twisted.internet import defer
7 from twisted.web2 import server, http, http_headers, static
8 from twisted.python import log, failure
9 from twisted.python.filepath import FilePath
11 from apt_dht_conf import config
12 from PeerManager import PeerManager
13 from HTTPServer import TopLevel
14 from MirrorManager import MirrorManager
15 from CacheManager import CacheManager
16 from Hash import HashObject
18 from util import findMyIPAddr
20 download_dir = 'cache'
23 def __init__(self, dht):
24 log.msg('Initializing the main apt_dht application')
25 self.cache_dir = FilePath(config.get('DEFAULT', 'cache_dir'))
26 if not self.cache_dir.child(download_dir).exists():
27 self.cache_dir.child(download_dir).makedirs()
28 self.db = DB(self.cache_dir.child('apt-dht.db'))
30 self.dht.loadConfig(config, config.get('DEFAULT', 'DHT'))
31 self.dht.join().addCallbacks(self.joinComplete, self.joinError)
32 self.http_server = TopLevel(self.cache_dir.child(download_dir), self)
33 self.setDirectories = self.http_server.setDirectories
34 self.http_site = server.Site(self.http_server)
35 self.peers = PeerManager()
36 self.mirrors = MirrorManager(self.cache_dir)
37 other_dirs = [FilePath(f) for f in config.getstringlist('DEFAULT', 'OTHER_DIRS')]
38 self.cache = CacheManager(self.cache_dir.child(download_dir), self.db, other_dirs, self)
44 def joinComplete(self, result):
45 self.my_addr = findMyIPAddr(result, config.getint(config.get('DEFAULT', 'DHT'), 'PORT'))
47 raise RuntimeError, "IP address for this machine could not be found"
48 self.cache.scanDirectories()
50 def joinError(self, failure):
51 log.msg("joining DHT failed miserably")
53 raise RuntimeError, "IP address for this machine could not be found"
55 def check_freshness(self, req, path, modtime, resp):
56 log.msg('Checking if %s is still fresh' % path)
57 d = self.peers.get([path], "HEAD", modtime)
58 d.addCallback(self.check_freshness_done, req, path, resp)
61 def check_freshness_done(self, resp, req, path, orig_resp):
63 log.msg('Still fresh, returning: %s' % path)
66 log.msg('Stale, need to redownload: %s' % path)
67 return self.get_resp(req, path)
69 def get_resp(self, req, path):
72 log.msg('Trying to find hash for %s' % path)
73 findDefer = self.mirrors.findHash(path)
75 findDefer.addCallbacks(self.findHash_done, self.findHash_error,
76 callbackArgs=(req, path, d), errbackArgs=(req, path, d))
77 findDefer.addErrback(log.err)
80 def findHash_error(self, failure, req, path, d):
82 self.findHash_done(HashObject(), req, path, d)
84 def findHash_done(self, hash, req, path, d):
85 if hash.expected() is None:
86 log.msg('Hash for %s was not found' % path)
87 self.lookupHash_done([], hash, path, d)
89 log.msg('Found hash %s for %s' % (hash.hexexpected(), path))
91 # Lookup hash in cache
92 locations = self.db.lookupHash(hash.expected())
93 self.getCachedFile(hash, req, path, d, locations)
95 def getCachedFile(self, hash, req, path, d, locations):
97 log.msg('Failed to return file from cache: %s' % path)
98 self.lookupHash(hash, path, d)
101 # Get the first possible location from the list
102 file = locations.pop(0)['path']
103 log.msg('Returning cached file: %s' % file.path)
106 resp = static.File(file.path).renderHTTP(req)
107 if isinstance(resp, defer.Deferred):
108 resp.addBoth(self._getCachedFile, hash, req, path, d, locations)
110 self._getCachedFile(resp, hash, req, path, d, locations)
112 def _getCachedFile(self, resp, hash, req, path, d, locations):
113 if isinstance(resp, failure.Failure):
114 log.msg('Got error trying to get cached file')
116 # Try the next possible location
117 self.getCachedFile(hash, req, path, d, locations)
120 log.msg('Cached response: %r' % resp)
122 if resp.code >= 200 and resp.code < 400:
125 # Try the next possible location
126 self.getCachedFile(hash, req, path, d, locations)
128 def lookupHash(self, hash, path, d):
129 log.msg('Looking up hash in DHT for file: %s' % path)
130 key = hash.normexpected(bits = config.getint(config.get('DEFAULT', 'DHT'), 'HASH_LENGTH'))
131 lookupDefer = self.dht.getValue(key)
132 lookupDefer.addCallback(self.lookupHash_done, hash, path, d)
134 def lookupHash_done(self, locations, hash, path, d):
136 log.msg('Peers for %s were not found' % path)
137 getDefer = self.peers.get([path])
138 getDefer.addCallback(self.cache.save_file, hash, path)
139 getDefer.addErrback(self.cache.save_error, path)
140 getDefer.addCallbacks(d.callback, d.errback)
142 log.msg('Found peers for %s: %r' % (path, locations))
143 # Download from the found peers
144 getDefer = self.peers.get(locations)
145 getDefer.addCallback(self.check_response, hash, path)
146 getDefer.addCallback(self.cache.save_file, hash, path)
147 getDefer.addErrback(self.cache.save_error, path)
148 getDefer.addCallbacks(d.callback, d.errback)
150 def check_response(self, response, hash, path):
151 if response.code < 200 or response.code >= 300:
152 log.msg('Download from peers failed, going to direct download: %s' % path)
153 getDefer = self.peers.get([path])
157 def new_cached_file(self, file_path, hash, urlpath, url = None):
158 """Add a newly cached file to the DHT.
160 If the file was downloaded, set url to the path it was downloaded for.
163 self.mirrors.updatedFile(url, file_path)
165 if self.my_addr and hash:
166 site = self.my_addr + ':' + str(config.getint('DEFAULT', 'PORT'))
167 full_path = urlunparse(('http', site, urlpath, None, None, None))
168 key = hash.norm(bits = config.getint(config.get('DEFAULT', 'DHT'), 'HASH_LENGTH'))
169 storeDefer = self.dht.storeValue(key, full_path)
170 storeDefer.addCallback(self.store_done, full_path)
171 storeDefer.addErrback(log.err)
173 def store_done(self, result, path):
174 log.msg('Added %s to the DHT: %r' % (path, result))