42 lines
1.5 KiB
Python
42 lines
1.5 KiB
Python
# Licensed under the Apache License, Version 2.0 (the "License"); you may
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# not use this file except in compliance with the License. You may obtain
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# a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
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# License for the specific language governing permissions and limitations
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# under the License.
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from oslo_db.sqlalchemy import session
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class DBConnection(object):
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"""Context manager class which handles a DB connection.
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An existing connection can be passed as a parameter. When
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nested block is complete the new connection will be closed.
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This class is not thread safe.
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"""
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def __init__(self, connection_url, connection=None):
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self.connection = connection
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self.connection_url = connection_url
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self.new_engine = False
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def __enter__(self):
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self.new_engine = self.connection is None
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if self.new_engine:
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self.engine = session.create_engine(self.connection_url)
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self.connection = self.engine.connect()
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return self.connection
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def __exit__(self, type, value, traceback):
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if self.new_engine:
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try:
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self.connection.close()
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finally:
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self.engine.dispose()
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