def _remove_stale_session(util: ConsulUtil) -> None:
'''Destroys a stale RC leader session if it exists or does nothing otherwise.
An RC leader session may survive 'hctl shutdown'. In such a case 'leader'
key will contain a garbage value 'elect2805' but the session will be alive
and thus RC leader will not be re-elected.
'''
if not util.kv.kv_get_raw('leader'):
# No leader key means that there can be no stale RC leader session for
# sure. We're starting for the first time against a fresh Consul KV.
return
sess = util.get_leader_session_no_wait()
# We might face situation where we have stale session such that we have
# 'session' present but 'value' is not present for leader key.
# In such situation we need to destroy the session so that RC re-election
# can be triggered automatically
if util.is_leader_value_present_for_session():
node = util.get_leader_node()
if re.match(r'^elect[\d]+$', node):
LOG.debug(
'Stale leader session found: RC leader session %s is '
'found while the leader node seems to be '
'stub: %s', sess, node)
util.destroy_session(sess)
LOG.debug('Stale session %s destroyed '
'to enable RC re-election', sess)
else:
util.destroy_session(sess)
LOG.debug('Stale session %s destroyed to enable RC re-election', sess)
def send_entrypoint_request_reply(self, message: EntrypointRequest):
reply_context = message.reply_context
req_id = message.req_id
remote_rpc_endpoint = message.remote_rpc_endpoint
process_fid = message.process_fid
LOG.debug('Processing entrypoint request from remote endpoint'
" '{}', process fid {}".format(remote_rpc_endpoint,
str(process_fid)))
sess = principal_rm = confds = None
try:
prov = ConsulUtil()
sess = prov.get_leader_session_no_wait()
principal_rm = prov.get_session_node(sess)
confds = prov.get_confd_list()
except Exception:
LOG.exception('Failed to get the data from Consul.'
' Replying with EAGAIN error code.')
self._ffi.entrypoint_reply(reply_context, req_id.to_c(), EAGAIN, 0,
make_array(FidStruct, []),
make_array(c.c_char_p, []), 0,
self.rm_fid.to_c(), None)
LOG.debug('Reply sent')
return
rc_quorum = int(len(confds) / 2 + 1)
rm_eps = None
for svc in confds:
if svc.node == principal_rm:
rm_eps = svc.address
break
if not rm_eps:
raise RuntimeError('No RM node found in Consul')
confd_fids = [x.fid.to_c() for x in confds]
confd_eps = [make_c_str(x.address) for x in confds]
LOG.debug('Passing the entrypoint reply to hax.c layer')
self._ffi.entrypoint_reply(reply_context, req_id.to_c(), 0,
len(confds),
make_array(FidStruct, confd_fids),
make_array(c.c_char_p,
confd_eps), rc_quorum,
self.rm_fid.to_c(), make_c_str(rm_eps))
LOG.debug('Entrypoint request has been replied to')
def _remove_stale_session(util: ConsulUtil) -> None:
'''Destroys a stale RC leader session if it exists or does nothing otherwise.
An RC leader session may survive 'hctl shutdown'. In such a case 'leader'
key will contain a garbage value 'elect2805' but the session will be alive
and thus RC leader will not be re-elected.
'''
if not util.kv.kv_get_raw('leader'):
# No leader key means that there can be no stale RC leader session for
# sure. We're starting for the first time against a fresh Consul KV.
return
sess = util.get_leader_session_no_wait()
node = util.get_leader_node()
if re.match(r'^elect[\d]+$', node):
LOG.debug(
'Stale leader session found: RC leader session %s is '
'found while the leader node seems to be stub: %s', sess, node)
util.destroy_session(sess)
LOG.debug('Stale session %s destroyed to enable RC re-election', sess)