###############################################################################
#
# The MIT License (MIT)
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# Copyright (c) Crossbar.io Technologies GmbH
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from twisted.internet.task import react
from twisted.internet.defer import inlineCallbacks

import txaio
from txaioetcd import Client, KeySet


@inlineCallbacks
def main(reactor):
    # create an etcd client
    etcd = Client(reactor)

    # retrieve etcd cluster status
    status = yield etcd.status()
    print(status)

    # callback invoked for every change
    def on_change(kv):
        print('on_change: {}'.format(kv))

    # start watching on given keys or key sets
    # when the key sets overlap, the callback might get called multiple
    # times, once for each key set matching an event
    keys = [KeySet(b'mykey2', b'mykey5'), KeySet(b'mykey', prefix=True)]
    d = etcd.watch(keys, on_change)

    # stop after 10 seconds
    print('watching for 1s ..')
    yield txaio.sleep(1)

    etcd.set(b'mykey10', b'Test')

    print('watching for 3s ..')
    yield txaio.sleep(3)


    d.cancel()


if __name__ == '__main__':
    txaio.start_logging(level='info')
    react(main)
