Bug #4569 » 0002-Fix-Fixed-enricher-failure-on-DB-restart.patch
| lib/mentat/services/sqlstorage.py | ||
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import copy |
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import sqlalchemy |
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from sqlalchemy.orm import Query |
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# |
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# Custom libraries |
| ... | ... | |
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_MANAGER = None |
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class RetryingQuery(Query): |
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""" |
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An override of SQLAlchemy's Query class, allowing for recovery from a lost DB |
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connection. |
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""" |
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def _execute_and_instances(self, querycontext): |
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for _ in range(2): |
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try: |
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return super()._execute_and_instances(querycontext) |
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except sqlalchemy.exc.OperationalError: |
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self.session.close() |
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continue |
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class StorageService: |
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""" |
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Proxy object for working with persistent SQL storages. Maintains and provides |
| ... | ... | |
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""" |
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self.dbengine = sqlalchemy.engine_from_config(enginecfg, prefix = '') |
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self.sessionmaker = sqlalchemy.orm.sessionmaker(bind = self.dbengine) |
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self.session = self.sessionmaker() |
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self.session = self.sessionmaker(query_cls = RetryingQuery)
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def __del__(self): |
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self.close() |