def obtain(self, filename):
# define message
msg = (
"mid:"
+ str(self.pid)
+ "|"
+ str(2222 + self.pid * 10)
+ "|"
+ str(self.msgid)
+ ",search:"
+ filename
+ ",TTL=10"
)
mid = msg.split(",")[0].split(":")[1]
# read mid_list from file 'msg_list'
mid_list = rw.readList("msg_list.txt")
# update mid_list
mid_list.append(mid)
rw.write("msg_list.txt", mid_list)
# read name_list from file 'req_list'
name_list = rw.readList("req_list.txt")
# update name_list
name_list.append(filename)
rw.write("req_list.txt", name_list)
# broadcast message to its neighbor
for n in self.neighbor:
self.s = socket.socket()
self.host = socket.gethostname()
self.port = 2222 + 10 * n
print "connect port: " + str(self.port)
self.s.connect((self.host, self.port))
self.s.send(msg)
self.s.close()
print "searching... ..."
def push(self, name, version):
#send update msg to all peers
self.msgid += 1
msg = 'mid:' + str(self.pid) + '|' + str(self.port) + '|update|' + str(self.msgid) + ',update:' + name + ',version:' + str(version)
mid = msg.split(',')[0].split(':')[1]
#read mid_list from file 'msg_list'
mid_list = rw.readList('msg_list.txt')
#update mid_list
mid_list.append(mid)
rw.write('msg_list.txt', mid_list)
broadcast = autobroadcast.Auto(msg, self.neighbor)
broadcast.start()
broadcast.join()
def reconn(self):
#reconnect to response peer
self.s = socket.socket()
self.host = socket.gethostname()
self.port = int(self.mid.split('|')[1])
self.s.connect((self.host, self.port))
print 'reconnect to ' + self.mid
self.s.send(self.msg)
#download metadata & file from response peer
metadata = json.loads(self.s.recv(1024))
#download file by chunks
i = 0
content = ''
while i != 1:
chunk = self.s.recv(1024)
if len(chunk) == 0:
i = 1
else:
content += chunk
self.s.close()
path = os.path.join(os.getcwd(), 'files', 'download', self.name)
rw.writeFile(path, content)
#read name_list from file 'req_list'
name_list = rw.readList('req_list.txt')
#update name_list
name_list.remove(self.name)
rw.write('req_list.txt', name_list)
#update metadata
meta_dict = rw.readDict('metadata.txt')
if 'download' in meta_dict.keys():
meta_dict['download'][self.name] = metadata
else:
file_dict = {}
file_dict[self.name] = metadata
meta_dict['download'] = file_dict
rw.write('metadata.txt', meta_dict)
print 'receive file: ' + self.name
def run(self):
#define the server thread
self.s = socket.socket()
self.host = socket.gethostname()
self.port = 2222 + self.pid * 10
self.s.bind((self.host, self.port))
self.s.listen(5)
while True:
#listen for connection
c, addr = self.s.accept()
print '\nGot connection from ', addr
#initialize file index
original_index = self.fileindex('original')
download_index = self.fileindex('download')
index = original_index + download_index
#receive message
msg = c.recv(1024)
#parse & analyze message
mid = msg.split(',')[0].split(':')[1]
action = msg.split(',')[1].split(':')[0]
name = msg.split(',')[1].split(':')[1]
if action == 'search':
print 'search ' + name
ttl = msg.split(',')[2].split('=')[1]
#read mid_list from file 'msg_list'
mid_list = rw.readList('msg_list.txt')
#decide broadcast or not
if int(ttl) == 1 or mid in mid_list:
print 'file dont need to pass'
else:
#update mid_list in file 'msg_list'
mid_list.append(mid)
rw.write('msg_list.txt', mid_list)
#decrease the ttl value by 1 after broadcast for once
rmsg = msg.rsplit(ttl, 1)
msg = str(int(ttl)-1).join(rmsg)
#start autobroadcast thread (details in autobroadcast.py module)
broadcast = autobroadcast.Auto(msg, self.neighbor)
broadcast.start()
broadcast.join()
if name in index:
#check file's state
meta_dict = rw.readDict('metadata.txt')
if (name in original_index and (meta_dict['original'][name]['state'] == 'valid' or meta_dict['download'][name]['state'] == 'valid')):
#start hitresponse thread (details in hitresponse.py module)
msg = 'mid:' + str(self.pid) + '|' + str(self.port) + ',response:' + name
hit = hitresponse.Hit(msg, mid)
hit.start()
hit.join()
else:
'file state is not qualified'
else:
print 'no file match, pass to neighbors'
elif action == 'update':
print 'update ' + name
#read mid_list from file 'msg_list'
mid_list = rw.readList('msg_list.txt')
#decide broadcast or not
if mid in mid_list:
print 'update dont need to pass'
else:
#update mid_list in file 'msg_list'
mid_list.append(mid)
rw.write('msg_list.txt', mid_list)
#start autobroadcast thread (details in autobroadcast.py module)
broadcast = autobroadcast.Auto(msg, self.neighbor)
broadcast.start()
broadcast.join()
if name in download_index:
#set file state to invalid
meta_dict = rw.readDict('metadata.txt')
meta_dict['download'][name]['state'] = 'invalid'
rw.write('metadata.txt', meta_dict)
else:
print 'no file need to update, pass to neighbors'
elif action == 'check':
print 'check ' + name
#check the original file's version
version = int(msg.split(',')[2].split(':')[1])
TTR = int(msg.split(',')[3].split(':')[1])
meta_dict = rw.readDict('metadata.txt')
if meta_dict['original'][name]['version'] == version:
#if same version, send a new TTR.
newTTR = 2 * TTR
msg = 'mid:' + str(self.pid) + '|' + str(self.port) + ',checkresponse:' + name + ',state:valid,TTR:' + str(newTTR)
else:
#send Invalid & new version exist.
msg = 'mid:' + str(self.pid) + '|' + str(self.port) + ',checkresponse:' + name + ',state:invalid'
hit = hitresponse.Hit(msg, mid)
hit.start()
hit.join()
elif action == 'checkresponse':
print 'checkresponse ' + name
#update the metadata
state = str(msg.split(',')[2].split(':')[1])
if state == 'valid':
TTR = int(msg.split(',')[3].split(':')[1])
#change TTR to 2TTR. (details in pullrenew.py module)
pullrenew.renew('TTR', name, TTR)
#change state from 'TTR Expired' back to 'valid' (details in pullrenew.py module)
pullrenew.renew('state', name, state)
elif state == 'invalid':
#change state from 'TTR Expired' back to 'invalid' (details in pullrenew.py module)
pullrenew.renew('state', name, state)
elif action == 'response':
#start reconnect thread (details in reconnect.py module)
print 'response ' + name + ' from ' + mid
#read name_list from file 'req_list'
name_list = rw.readList('req_list.txt')
#decide reconnect or not
if name in name_list:
msg = 'mid:' + str(self.pid) + '|' + str(self.port) + ',obtain:' + name
connect = reconnect.Connect(msg, mid, name)
connect.start()
connect.join()
else:
print 'file has been obtained'
elif action == 'obtain':
print 'obtain ' + name
#start transfer directly to original peer
if name in original_index:
path = os.path.join(os.getcwd(), 'files', 'original', name)
metadata = rw.readDict('metadata.txt')['original'][name]
elif name in download_index:
path = os.path.join(os.getcwd(), 'files', 'download', name)
metadata = rw.readDict('metadata.txt')['download'][name]
#send metadata & file
c.sendall(json.dumps(metadata))
#slice file into chunks by buffer
content = rw.readFile(path)
i = 0
while i <= len(content):
chunk = buffer(content, i, 1024)
c.sendall(chunk)
i += 1024
print 'send file: ' + name
c.close()