#!/usr/bin/env python

# Copyright 2016 Google Inc. All Rights Reserved.
#
# 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.

"""This application demonstrates how to perform basic operations on logs and
log entries with Stackdriver Logging.

For more information, see the README.md under /logging and the
documentation at https://cloud.google.com/logging/docs.
"""

import argparse

from google.cloud import logging


# [START logging_write_log_entry]
def write_entry(logger_name):
    """Writes log entries to the given logger."""
    logging_client = logging.Client()

    # This log can be found in the Cloud Logging console under 'Custom Logs'.
    logger = logging_client.logger(logger_name)

    # Make a simple text log
    logger.log_text('Hello, world!')

    # Simple text log with severity.
    logger.log_text('Goodbye, world!', severity='ERROR')

    # Struct log. The struct can be any JSON-serializable dictionary.
    logger.log_struct({
        'name': 'King Arthur',
        'quest': 'Find the Holy Grail',
        'favorite_color': 'Blue'
    })

    print('Wrote logs to {}.'.format(logger.name))
# [END logging_write_log_entry]


# [START logging_list_log_entries]
def list_entries(logger_name):
    """Lists the most recent entries for a given logger."""
    logging_client = logging.Client()
    logger = logging_client.logger(logger_name)

    print('Listing entries for logger {}:'.format(logger.name))

    for entry in logger.list_entries():
        timestamp = entry.timestamp.isoformat()
        print('* {}: {}'.format
              (timestamp, entry.payload))
# [END logging_list_log_entries]


# [START logging_delete_log]
def delete_logger(logger_name):
    """Deletes a logger and all its entries.

    Note that a deletion can take several minutes to take effect.
    """
    logging_client = logging.Client()
    logger = logging_client.logger(logger_name)

    logger.delete()

    print('Deleted all logging entries for {}'.format(logger.name))
# [END logging_delete_log]


if __name__ == '__main__':
    parser = argparse.ArgumentParser(
        description=__doc__,
        formatter_class=argparse.RawDescriptionHelpFormatter
    )
    parser.add_argument(
        'logger_name', help='Logger name', default='example_log')
    subparsers = parser.add_subparsers(dest='command')
    subparsers.add_parser('list', help=list_entries.__doc__)
    subparsers.add_parser('write', help=write_entry.__doc__)
    subparsers.add_parser('delete', help=delete_logger.__doc__)

    args = parser.parse_args()

    if args.command == 'list':
        list_entries(args.logger_name)
    elif args.command == 'write':
        write_entry(args.logger_name)
    elif args.command == 'delete':
        delete_logger(args.logger_name)