pickle-warehouse 0.0.12

How to use

Pickle Warehouse provides a dictionary-like object that is associated with a particular directory on your computer.

from pickle_warehouse import Warehouse
warehouse = Warehouse('/tmp/a-directory')

The keys correspond to files, and the values get pickled to the files.

warehouse['filename'] = range(100)

import pickle
range(100) == pickle.load(open('/tmp/a-directory/filename', 'rb'))

You can also read and delete things.

# Read
range(100) == warehouse['filename']

# Delete
del(warehouse['filename'])

The coolest part is that the key gets interpreted in a fancy way. Aside from strings and string-like objects, you can use iterables of strings; all of these indices refer to the file /tmp/a-directory/foo/bar/baz:

warehouse[('foo','bar','baz')]
warehouse[['foo','bar','baz']]

If you pass a relative path to a file, it will be broken up as you’d expect; that is, strings get split on slashes and backslashes.

warehouse['foo/bar/baz']
warehouse['foo\\bar\\baz']

Note well: Specifying an absolute path won’t save things outside the warehouse directory.

warehouse['/foo/bar/baz'] # -> foo, bar, baz
warehouse['C:\\foo\\bar\\baz'] # -> c, foo, bar, baz
                               # (lowercase "c")

If you pass a URL, it will also get broken up in a reasonable way.

# /tmp/a-directory/http/thomaslevine.com/!/?foo=bar#baz
warehouse['http://thomaslevine.com/!/?foo=bar#baz']

# /tmp/a-directory/thomaslevine.com/!?foo=bar#baz
warehouse['thomaslevine.com/!?foo=bar#baz']

Dates and datetimes get converted to YYYY-MM-DD format.

import datetime

# /tmp/a-directory/2014-02-26
warehouse[datetime.date(2014,2,26)]
warehouse[datetime.datetime(2014,2,26,13,6,42)]

And you can mix these formats!

# /tmp/a-directory/http/thomaslevine.com/open-data/2014-02-26
warehouse[('http://thomaslevine.com/open-data', datetime.date(2014,2,26))]

It also has typical dictionary methods like keys, values, items, and update.

When to use

pickle-warehouse is for when you want a persistant store of Python objects. If you want an in-memory pickle store, look at _pickleDB: https://pythonhosted.org/pickleDB/.

To do

Add a write-once option