Source Code for Module tlib.base.OracleConnector

  1  from tlib.base.ExceptionHelper import TLibException 
  2  import cx_Oracle 
  3   
  4   
  5 -class ConnectionError(TLibException): 
  6 -    def __init__(self, err_code, err_description): 
  7          self.code, self.description = err_code, err_description 
  8 -    def __str__(self): 
  9          return 'Connection to DB FAILURE with error(/code: description/) /%d: %s/' % (self.code, self.description) 
 10   
 11   
 12 -class AutoCommitError(TLibException): 
 13 -    def __init__(self, value): 
 14          self.value = value 
 15 -    def __str__(self): 
 16          return "Wrong argument '%s' passed in <get_autocommit_status> function. Valid args are str: 'local', 'global' or 'session'." % self.value 
 17   
 18   
 19 -class QueryError(TLibException): 
 20 -    def __init__(self, err_code, err_description): 
 21          self.code, self.description = err_code, err_description 
 22 -    def __str__(self): 
 23          return 'query function FAILURE with error(/code: description/) /%d: %s/ %d: %s' % (self.code, self.description) 
 24   
 25   
 26 -class ExecuteError(TLibException): 
 27 -    def __init__(self, err_code, err_description): 
 28          self.code, self.description = err_code, err_description 
 29 -    def __str__(self): 
 30          return 'execute function FAILURE with error (/code: description/) /%d: %s/' % (self.code, self.description) 
 31   
 32   
 33 -class OracleConnector(object): 
 34      """ 
 35      Connects to MySQL DB, executes queries 
 36      Autocommit is disabled by default, commit is done with commit function 
 37      Warnings are turned into exceptions 
 38      """ 
 39 -    def __init__(self, sid, username=None, password=None, host=None, port=None): 
 40          """ 
 41          Initialize DB connection. Turning warning into exceptions 
 42          """ 
 43          self.db = None 
 44          try: 
 45              dsn_tns = sid 
 46              if host: 
 47                  dsn_tns = cx_Oracle.makedsn(host, port, sid) 
 48              self.db = cx_Oracle.connect(user=username, password=password, dsn=dsn_tns) 
 49              self.cursor = self.db.cursor() 
 50              self.db.autocommit = 0   # in case of autocommit will change by default to ON in future 
 51          except cx_Oracle.Error, err: 
 52              raise ConnectionError(err.args[0], err.args[1]) 
 53   
 54   
 55 -    def get_autocommit_status(self): 
 56          """ 
 57          returns tuple Autocommit status i.e. 1 for True and 0 for False 
 58          """ 
 59          return self.db.autocommit 
 60   
 61   
 62 -    def query_select(self, query): 
 63          """ 
 64          Send/execute SELECT queries, returns data from DB 
 65          :param: str MySQL query 
 66          :return: tuple with arguments dictionaries, each dictionary is a row of DB i.e. ({row_first}, {row_second}, ... ,{row_last}) 
 67          """ 
 68          try: 
 69              self.cursor.execute(query) 
 70              return self.cursor.fetchall() 
 71          except cx_Oracle.Error, err: 
 72              raise QueryError(err.args[0], err.args[1]) 
 73   
 74 -    def query_execute(self, query): 
 75          """ 
 76          Sends query to DB. Can be DELETE, UPDATE 
 77          :param: str query 
 78          :return: dict {DictCursor} 
 79          """ 
 80          try: 
 81              self.cursor.execute(query) 
 82              return self.cursor 
 83          except cx_Oracle.Error, err: 
 84              raise ExecuteError(err.args[0], err.args[1]) 
 85   
 86 -    def commit(self): 
 87          """ 
 88          Commits all changes, returns Exception in case of failure 
 89          """ 
 90          self.db.commit() 
 91   
 92 -    def rollback(self): 
 93          """ 
 94          Rolls back all commits, returns exception in case of failure 
 95          """ 
 96          self.db.rollback() 
 97   
 98 -    def close_cursor(self): 
 99          """ 
100          Close cursor. Connection to DB is still open, new cursor can be created 
101          """ 
102          self.cursor.close() 
103   
104 -    def close_db(self): 
105          """ 
106          Close DB connection. All uncommitted changes are lost 
107          """ 
108          self.db.close() 
109   
110 -    def __del__(self): 
111          self.cursor.close() 
112          self.db.close() 
113