lock.py

# ------------------------------------------------------------
# Copyright 2021 The Dapr Authors
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#     http://www.apache.org/licenses/LICENSE-2.0
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
# ------------------------------------------------------------

from dapr.clients import DaprClient
import warnings


def main():
    # Lock parameters
    store_name = 'lockstore'  # as defined in components/lockstore.yaml
    resource_id = 'example-lock-resource'
    client_id = 'example-client-id'
    expiry_in_seconds = 60

    with DaprClient() as dapr:
        print('Will try to acquire a lock from lock store named [%s]' % store_name)
        print('The lock is for a resource named [%s]' % resource_id)
        print('The client identifier is [%s]' % client_id)
        print('The lock will will expire in %s seconds.' % expiry_in_seconds)

        with dapr.try_lock(store_name, resource_id, client_id, expiry_in_seconds) as lock_result:
            assert lock_result.success, 'Failed to acquire the lock. Aborting.'
            print('Lock acquired successfully!!!')

        # At this point the lock was released - by magic of the `with` clause ;)
        unlock_result = dapr.unlock(store_name, resource_id, client_id)
        print('We already released the lock so unlocking will not work.')
        print('We tried to unlock it anyway and got back [%s]' % unlock_result.status)


if __name__ == '__main__':
    # Suppress "The Distributed Lock API is an Alpha" warnings
    warnings.simplefilter('ignore')
    main()