def delete_group(self, group_id):
@_translate_failures
def _delete_group():
prefix_group = self._prefix_group(group_id)
members = self.client.get_prefix(prefix_group)
if len(members) > 1:
raise coordination.GroupNotEmpty(group_id)
encoded_group = self._encode_group_id(group_id)
txn = {
'compare': [{
'key': encoded_group,
'result': 'NOT_EQUAL',
'target': 'VERSION',
'version': 0
}],
'success': [{
'request_delete_range': {
'key': encoded_group,
}
}],
'failure': []
}
result = self.client.transaction(txn)
if not result.get("succeeded"):
raise coordination.GroupNotCreated(group_id)
return coordination.CoordinatorResult(
self._executor.submit(_delete_group))
def create_group(self, group_id):
@_translate_failures
def _create_group():
encoded_group = self._encode_group_id(group_id)
txn = {
'compare': [{
'key': encoded_group,
'result': 'EQUAL',
'target': 'VERSION',
'version': 0
}],
'success': [{
'request_put': {
'key': encoded_group,
# We shouldn't need a value, but etcd3gw needs it for
# now
'value': encoded_group
}
}],
'failure': []
}
result = self.client.transaction(txn)
if not result.get("succeeded"):
raise coordination.GroupAlreadyExist(group_id)
return coordination.CoordinatorResult(
self._executor.submit(_create_group))
def get_groups(self):
@_translate_failures
def _get_groups():
groups = self.client.get_prefix(self.GROUP_PREFIX)
return [
group[1]['key'][len(self.GROUP_PREFIX):-1] for group in groups]
return coordination.CoordinatorResult(
self._executor.submit(_get_groups))
def get_member_capabilities(self, group_id, member_id):
@_translate_failures
def _get_member_capabilities():
prefix_member = self._prefix_group(group_id) + member_id
result = self.client.get(prefix_member)
if not result:
raise coordination.MemberNotJoined(group_id, member_id)
return utils.loads(result[0])
return coordination.CoordinatorResult(
self._executor.submit(_get_member_capabilities))
def delete_group(self, group_id):
def _delete_group():
with self._lock:
group_list = self._read_group_list()
if group_id not in group_list:
raise coordination.GroupNotCreated(group_id)
group_list.remove(group_id)
self._write_group_list(group_list)
return coordination.CoordinatorResult(
self._executor.submit(_delete_group))
def create_group(self, group_id):
def _create_group():
with self._lock:
group_list = self._read_group_list()
if group_id in group_list:
raise coordination.GroupAlreadyExist(group_id)
group_list.add(group_id)
self._write_group_list(group_list)
return coordination.CoordinatorResult(
self._executor.submit(_create_group))
def update_capabilities(self, group_id, capabilities):
@_translate_failures
def _update_capabilities():
prefix_member = self._prefix_group(group_id) + self._member_id
result = self.client.get(prefix_member)
if not result:
raise coordination.MemberNotJoined(group_id, self._member_id)
self.client.put(prefix_member, utils.dumps(capabilities),
lease=self._membership_lease)
return coordination.CoordinatorResult(
self._executor.submit(_update_capabilities))
def join_group(self, group_id, capabilities=b""):
@_retry.retry()
@_translate_failures
def _join_group():
prefix_group = self._prefix_group(group_id)
prefix_member = prefix_group + self._member_id
members = self.client.get_prefix(prefix_group)
encoded_member = _encode(prefix_member)
group_metadata = None
for cap, metadata in members:
if metadata['key'] == prefix_member:
raise coordination.MemberAlreadyExist(group_id,
self._member_id)
if metadata['key'] == prefix_group:
group_metadata = metadata
if group_metadata is None:
raise coordination.GroupNotCreated(group_id)
encoded_group = self._encode_group_id(group_id)
txn = {
'compare': [{
'key': encoded_group,
'result': 'EQUAL',
'target': 'VERSION',
'version': int(group_metadata['version'])
}],
'success': [{
'request_put': {
'key': encoded_member,
'value': _encode(utils.dumps(capabilities)),
'lease': self._membership_lease.id
}
}],
'failure': []
}
result = self.client.transaction(txn)
if not result.get('succeeded'):
raise _retry.TryAgain
else:
self._joined_groups.add(group_id)
return coordination.CoordinatorResult(
self._executor.submit(_join_group))
def leave_group(self, group_id):
@_translate_failures
def _leave_group():
prefix_group = self._prefix_group(group_id)
prefix_member = prefix_group + self._member_id
members = self.client.get_prefix(prefix_group)
for capabilities, metadata in members:
if metadata['key'] == prefix_member:
break
else:
raise coordination.MemberNotJoined(group_id, self._member_id)
self.client.delete(prefix_member)
self._joined_groups.discard(group_id)
return coordination.CoordinatorResult(
self._executor.submit(_leave_group))
def get_members(self, group_id):
@_translate_failures
def _get_members():
prefix_group = self._prefix_group(group_id)
members = set()
group_found = False
for cap, metadata in self.client.get_prefix(prefix_group):
if metadata['key'] == prefix_group:
group_found = True
else:
members.add(metadata['key'][len(prefix_group):])
if not group_found:
raise coordination.GroupNotCreated(group_id)
return members
return coordination.CoordinatorResult(
self._executor.submit(_get_members))
def get_groups(self):
return coordination.CoordinatorResult(
self._executor.submit(self._get_groups_handler))
