def dispatch_join(source, req_code, req_type, data):
#if this node is prev ( this.succ== is_responsible ) update its next to source put its ip to prev datum and forward request to next
#if this node is_resp === is next update its prev to source put its ip to succ datum and get same_keys , new_keys and respond to source
#if nothing of the above just forward to next node
if (is_responsible(data['key'])):
data['succ'] = node.ip_port
same_new = node.get_same_new_keys(data['key'])
data['same_keys'] = same_new[0]
data['new_keys'] = same_new[1]
if (node.is_alone()):
# special case --> here we are previous also so we must fix those values too
node.succ_ip_port = source
node.prev_ip_port = source
data['prev'] = node.ip_port
#respond to source
node.prev_ip_port = source
resp = make_resp(source, req_type, data, req_code)
post_resp_thread(source, resp)
elif (succ_is_responsible(data['key'])):
temp = node.succ_ip_port
node.succ_ip_port = source
data['prev'] = node.ip_port
req = make_same_req(source, req_type, data, req_code)
post_req_thread(temp, req)
else:
req = make_same_req(source, req_type, data, req_code)
post_req_thread(node.succ_ip_port, req)
return
def dispatch_join(source, req_code, req_type, data):
#if this node is prev ( this.succ== is_responsible ) update its next to source put its ip to prev datum and forward request to next
#if this node is_resp === is next update its prev to source put its ip to succ datum and get same_keys , new_keys and respond to source
#if nothing of the above just forward to next node
#### THIS IS ONLY FOR BOOTSTRAP NODE --> IT SENDS THE NODE THAT JOINS REPN AND REP_TYPE INFORMATION####
resp = make_resp(source, 'join_vars', {
'repn': node.get_replicas(),
'rep_type': node.get_rep_type()
}, req_code)
post_resp_to(source, resp)
#######################################################################################################
if (is_responsible(data['key'])):
######only for bootstrap cause he is the first to receive join req
######if he is responsible its the only case when we dont pass from the prev
######so we must set the data['prev']=node.prev_ip_port
###### and also send request to prev to update its succ to the source
data['prev'] = node.prev_ip_port
post_resp_to(node.prev_ip_port, {
'type': 'set_neighboors',
'prev': "None",
'succ': source
})
######
data['succ'] = node.ip_port
same_new = node.get_same_new_keys(data['key'])
data['same_keys'] = same_new[0]
data['new_keys'] = same_new[1]
if (node.is_alone()):
# special case --> here we are previous also so we must fix those values too
node.succ_ip_port = source
node.prev_ip_port = source
data['prev'] = node.ip_port
#respond to source
node.prev_ip_port = source
resp = make_resp(source, req_type, data, req_code)
post_resp_thread(source, resp)
elif (succ_is_responsible(data['key'])):
temp = node.succ_ip_port
node.succ_ip_port = source
data['prev'] = node.ip_port
req = make_same_req(source, req_type, data, req_code)
post_req_thread(temp, req)
else:
req = make_same_req(source, req_type, data, req_code)
post_req_thread(node.succ_ip_port, req)
return
def is_responsible(key):
curr = node.id
prev = hash(node.prev_ip_port)
if node.is_alone():
# ara uparxei mono enas komvos sto chord
return True
elif prev > curr:
if (key > prev or key <= curr):
return True
else:
return False
else:
if (key > prev and key <= curr):
return True
else:
return False
def depart():
if request.method == 'POST':
if not node.get_isInChord():
return 'This node does not participate in Chord!\n'
else:
# Στις επόμενες 4 γραμμές, μαζεύω τα data που θα στείλω στον successor
global seqn
seqn = seqn + 1
req_code = str(seqn)
new_keys = node.keys_vals[0]
last_keys = node.keys_vals[node.get_replicas() - 1]
#send message to boot to find out K_nodes value
boot_resp = requests.post("http://" + node.boot_ip_port +
"/ntwresp",
json={'type': 'K_nodes'})
K_nodes = json.loads(boot_resp.text)['K_nodes']
data = {
'index': 0,
'new_keys': new_keys,
'last_keys': last_keys,
'K_nodes': K_nodes
}
if node.is_alone():
node.init_state()
return f"Node {node.ip_port} departed from the Chord!\n"
else:
#make depart request and post to next node--> it will update all the rm chain
req = make_req('depart', data, req_code)
post_req_thread(node.succ_ip_port, req)
while responses_dict.get(req_code, "None") == "None":
{}
responses_dict.pop(req_code)
# then take care of the neighbour pointers
# data = {'prev': node.prev_ip_port, 'succ': node.succ_ip_port, 'type':'set_neighboors'}
prev = node.prev_ip_port
succ = node.succ_ip_port
if node.is_duo():
# an exoume mono 2 nodes tote prepei na steiloume na enimerwsei kai ton next kai ton prev o enas mas geitonas
#to parakatw tha perimenei mexri na lavoume apantisi
post_resp_to(node.prev_ip_port, {
'prev': prev,
'succ': succ,
'type': 'set_neighboors'
})
else:
#an uparxoun toul 3 komvoi stelnoume kai ston prev kai ston next na enimerwsoun mono ton enan geitona tous ekastos
post_resp_to(node.prev_ip_port, {
'prev': "None",
'succ': succ,
'type': 'set_neighboors'
})
post_resp_to(node.succ_ip_port, {
'prev': prev,
'succ': "None",
'type': 'set_neighboors'
})
# Then return the node to dafault state
node.init_state()
post_resp_to(node.boot_ip_port, {'type': 'dec_number'})
return f"Node {node.ip_port} successfully departed from Chord!\n"