JezK
Edit File: anydbm.py
"""Generic interface to all dbm clones. Instead of import dbm d = dbm.open(file, 'w', 0666) use import anydbm d = anydbm.open(file, 'w') The returned object is a dbhash, gdbm, dbm or dumbdbm object, dependent on the type of database being opened (determined by whichdb module) in the case of an existing dbm. If the dbm does not exist and the create or new flag ('c' or 'n') was specified, the dbm type will be determined by the availability of the modules (tested in the above order). It has the following interface (key and data are strings): d[key] = data # store data at key (may override data at # existing key) data = d[key] # retrieve data at key (raise KeyError if no # such key) del d[key] # delete data stored at key (raises KeyError # if no such key) flag = key in d # true if the key exists list = d.keys() # return a list of all existing keys (slow!) Future versions may change the order in which implementations are tested for existence, and add interfaces to other dbm-like implementations. """ class error(Exception): pass _names = ['dbhash', 'gdbm', 'dbm', 'dumbdbm'] _errors = [error] _defaultmod = None for _name in _names: try: _mod = __import__(_name) except ImportError: continue if not _defaultmod: _defaultmod = _mod _errors.append(_mod.error) if not _defaultmod: raise ImportError, "no dbm clone found; tried %s" % _names error = tuple(_errors) def open(file, flag='r', mode=0666): """Open or create database at path given by *file*. Optional argument *flag* can be 'r' (default) for read-only access, 'w' for read-write access of an existing database, 'c' for read-write access to a new or existing database, and 'n' for read-write access to a new database. Note: 'r' and 'w' fail if the database doesn't exist; 'c' creates it only if it doesn't exist; and 'n' always creates a new database. """ # guess the type of an existing database from whichdb import whichdb result=whichdb(file) if result is None: # db doesn't exist if 'c' in flag or 'n' in flag: # file doesn't exist and the new # flag was used so use default type mod = _defaultmod else: raise error, "need 'c' or 'n' flag to open new db" elif result == "": # db type cannot be determined raise error, "db type could not be determined" else: mod = __import__(result) return mod.open(file, flag, mode)