Revision 1869
Added by Aaron Marcuse-Kubitza over 12 years ago
| sql.py | ||
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# Database access |
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import copy |
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import random |
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import re |
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import sys |
| ... | ... | |
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else: raise NotImplementedError("Can't escape name for "+module+' database')
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return quote + name.replace(quote, '') + quote |
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##### Connection object
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##### Database connections
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db_engines = {
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'MySQL': ('MySQLdb', {'password': 'passwd', 'database': 'db'}),
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'PostgreSQL': ('psycopg2', {}),
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} |
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DatabaseErrors_set = set([DbException]) |
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DatabaseErrors = tuple(DatabaseErrors_set) |
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def _add_module(module): |
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DatabaseErrors_set.add(module.DatabaseError) |
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global DatabaseErrors |
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DatabaseErrors = tuple(DatabaseErrors_set) |
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def db_config_str(db_config): |
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return db_config['engine']+' database '+db_config['database'] |
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class DbConn: |
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def __init__(self, db): |
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self.db = db |
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def __init__(self, db_config, serializable=True): |
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self.db_config = db_config |
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self.serializable = serializable |
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self.__db = None |
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self.pkeys = {}
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self.index_cols = {}
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def __getattr__(self, name): |
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if name == '__dict__': raise Exception('getting __dict__')
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if name == 'db': return self._db() |
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else: raise AttributeError() |
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def __getstate__(self): |
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state = copy.copy(self.__dict__) # shallow copy |
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state['_DbConn__db'] = None # don't pickle the connection |
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return state |
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def _db(self): |
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if self.__db == None: |
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# Process db_config |
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db_config = self.db_config.copy() # don't modify input! |
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module_name, mappings = db_engines[db_config.pop('engine')]
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module = __import__(module_name) |
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_add_module(module) |
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for orig, new in mappings.iteritems(): |
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try: util.rename_key(db_config, orig, new) |
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except KeyError: pass |
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# Connect |
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self.__db = module.connect(**db_config) |
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# Configure connection |
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if self.serializable: run_raw_query(self, |
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'SET TRANSACTION ISOLATION LEVEL SERIALIZABLE') |
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return self.__db |
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connect = DbConn |
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##### Querying |
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def run_raw_query(db, query, params=None): |
| ... | ... | |
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except StopIteration: |
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if not create: raise |
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return put(db, table, row, pkey, row_ct_ref) # insert new row |
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##### Database connections |
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db_engines = {
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'MySQL': ('MySQLdb', {'password': 'passwd', 'database': 'db'}),
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'PostgreSQL': ('psycopg2', {}),
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} |
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DatabaseErrors_set = set([DbException]) |
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DatabaseErrors = tuple(DatabaseErrors_set) |
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def _add_module(module): |
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DatabaseErrors_set.add(module.DatabaseError) |
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global DatabaseErrors |
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DatabaseErrors = tuple(DatabaseErrors_set) |
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def connect(db_config, serializable=True): |
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db_config = db_config.copy() # don't modify input! |
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module_name, mappings = db_engines[db_config.pop('engine')]
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module = __import__(module_name) |
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_add_module(module) |
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for orig, new in mappings.iteritems(): |
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try: util.rename_key(db_config, orig, new) |
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except KeyError: pass |
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db = DbConn(module.connect(**db_config)) |
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if serializable: |
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run_raw_query(db, 'SET TRANSACTION ISOLATION LEVEL SERIALIZABLE') |
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return db |
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def db_config_str(db_config): |
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return db_config['engine']+' database '+db_config['database'] |
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Also available in: Unified diff
sql.py: DbConn: Made it picklable by establishing a connection on demand