Zookeeper

Example

zookeeper.py
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#!/usr/bin/env python3
import asab
import asab.zookeeper

# Specify a default configuration
asab.Config.add_defaults(
    {
        "my:zk": {
            # specify "servers": "..." here to provide addresses of Zookeeper servers
            "path": "asab"
        },
    }
)


class MyApplication(asab.Application):


    def __init__(self):
        super().__init__()

        # Loading the ASAB Zookeeper module
        self.add_module(asab.zookeeper.Module)

        # Locate the Zookeeper service
        zksvc = self.get_service("asab.ZooKeeperService")

        # Create the Zookeeper container
        self.ZkContainer = asab.zookeeper.ZooKeeperContainer(zksvc, 'my:zk')

        # Subscribe to the event that indicated the successful connection to the Zookeeper server(s)
        self.PubSub.subscribe("ZooKeeperContainer.started!", self._on_zk_ready)


    async def _on_zk_ready(self, event_name, zkcontainer):
        # If there is more than one ZooKeeper Container being initialized, this method is called at every Container initialization.
        # Then you need to check whether the specific ZK Container has been initialized.
        if zkcontainer == self.ZkContainer:
            path = self.ZkContainer.ZooKeeperPath + "/hello"
            await self.ZkContainer.ZooKeeper.ensure_path(path)
            print("The path in Zookeeper has been created.")


if __name__ == '__main__':
    app = MyApplication()
    app.run()