import time from datetime import datetime from os.path import join from typing import List from .classes import SpecificEtcdEntryBase class HostStatus: """Possible Statuses of ucloud host.""" alive = "ALIVE" dead = "DEAD" class HostEntry(SpecificEtcdEntryBase): """Represents Host Entry Structure and its supporting methods.""" def __init__(self, e): self.specs = None # type: dict self.hostname = None # type: str self.status = None # type: str self.last_heartbeat = None # type: str super().__init__(e) def update_heartbeat(self): self.status = HostStatus.alive self.last_heartbeat = time.strftime("%Y-%m-%d %H:%M:%S") def is_alive(self): last_heartbeat = datetime.strptime( self.last_heartbeat, "%Y-%m-%d %H:%M:%S" ) delta = datetime.now() - last_heartbeat if delta.total_seconds() > 60: return False return True def declare_dead(self): self.status = HostStatus.dead self.last_heartbeat = time.strftime("%Y-%m-%d %H:%M:%S") class HostPool: def __init__(self, etcd_client, host_prefix): self.client = etcd_client self.prefix = host_prefix @property def hosts(self) -> List[HostEntry]: _hosts = self.client.get_prefix(self.prefix, value_in_json=True) return [HostEntry(host) for host in _hosts] def get(self, key): if not key.startswith(self.prefix): key = join(self.prefix, key) v = self.client.get(key, value_in_json=True) if v: return HostEntry(v) return None def put(self, obj: HostEntry): self.client.put(obj.key, obj.value, value_in_json=True) def by_status(self, status, _hosts=None): if _hosts is None: _hosts = self.hosts return list(filter(lambda x: x.status == status, _hosts))