regobj 0.1.0

regobj: Pythonic object-based access to the Windows Registry

This module provides a thin wrapper around the standard _winreg module, allowing easier and more pythonic access to the Windows Registry.

All access to the registry is done through Key objects, which (surprise!) represent a specific registry key. To begin, there are pre-existing Key objects defined for the HKEY_* root keys, using both long and short names:

>>> HKEY_CURRENT_USER
<regobj Key 'HKEY_CURRENT_USER'>
>>> HKLM
<regobj Key 'HKEY_LOCAL_MACHINE'>

Traversing and creating subkeys is then as simple as ordinary python attribute access:

>>> HKCU.Software.Microsoft.Windows
<regobj Key 'HKEY_CURRENT_USER\Software\Microsoft\Windows'>
>>> HKCU.Software.MyTests
Traceback (most recent call last):
    ...
AttributeError: subkey 'MyTests' does not exist
>>> HKCU.Software.MyTests = Key
>>> HKCU.Software.MyTests
<regobj Key 'HKEY_CURRENT_USER\Software\MyTests'>
>>> del HKCU.Software.MyTests

Of course, for keys that don’t happen to be named like python identifiers, there are also methods that can accomplish the same thing. To help reduce visual clutter, calling a key object is a shorthand for attribute lookup:

>>> HKCU.Software.set_subkey("my-funny-key",Key)
>>> HKCU.Software.get_subkey("my-funny-key").SubKey = Key
>>> HKCU("Software\my-funny-key\SubKey")
<regobj Key 'HKEY_CURRENT_USER\Software\my-funny-key\SubKey'>
>>> HKCU.Software.del_subkey("my-funny-key")

The individual values contained in a key can be accessed using standard item access syntax. The returned objects will be instances of the Value class, with ‘name’, ‘type’ and ‘data’ attributes:

>>> HKCU.Software.Microsoft.Clock["iFormat"]
<regobj Value (iFormat,1,REG_SZ)>
>>> HKCU.Software.Microsoft.Clock["iFormat"].name
'iFormat'
>>> HKCU.Software.Microsoft.Clock["iFormat"].data
u'1'
>>> HKCU.Software.Microsoft.Clock["iFormat"].type
1
>>> HKCU.Software.Microsoft.Clock["notavalue"]
Traceback (most recent call last):
    ...
KeyError: "no such value: 'notavalue'"

Iterating over a key generates all the contained values, followed by all the contained subkeys. There are also methods to seperately iterate over just the values, and just the subkeys:

>>> winK = HKCU.Software.Microsoft.Windows
>>> winK["testvalue"] = 42
>>> for obj in winK:
...   print obj
<regobj Value (testvalue,42,REG_DWORD)>
<regobj Key 'HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion'>
<regobj Key 'HKEY_CURRENT_USER\Software\Microsoft\Windows\Shell'>
<regobj Key 'HKEY_CURRENT_USER\Software\Microsoft\Windows\ShellNoRoam'>
>>> [k.name for k in winK.subkeys()]
['CurrentVersion', 'Shell', 'ShellNoRoam']
>>> [v.data for v in winK.values()]
[42]
>>> del winK["testvalue"]

These iterators also provide efficient implementations of the __contains__ and __len__ methods, so they can be used as follows:

>>> "Shell" in HKCU.Software.Microsoft.Windows
True
>>> "Shell" in HKCU.Software.Microsoft.Windows.subkeys()
True
>>> "Shell" in HKCU.Software.Microsoft.Windows.values()
False
>>> len(HKCU.Software.Microsoft.Windows)
3
>>> len(HKCU.Software.Microsoft.Windows.values())
0

Finally, there is powerful support for specifying key and value structures at creation time. The simplest case has already been demonstrated, where setting a subkey to the Key class or to None will create it without any data:

>>> HKCU.Software.MyTests = None
>>> len(HKCU.Software.MyTests)
0

If a subkey is assigned an existing key object, the data from that key is copied into the subkey:

>>> HKCU.Software.MyTests = HKCU.Software.Microsoft.Windows
>>> len(HKCU.Software.MyTests)
3
>>> [k.name for k in HKCU.Software.MyTests]
['CurrentVersion', 'Shell', 'ShellNoRoam']
>>> del HKCU.Software.MyTests

If a subkey is assigned a dictionary, the structure of that dictionary is copied into the subkey. Scalar values become key values, while nested dictionaries create subkeys:

>>> HKCU.Software.MyTests = {"val1":7, "stuff":{"a":1,"c":2,"e":3}}
>>> len(HKCU.Software.MyTests)
2
>>> [v.name for v in HKCU.Software.MyTests.values()]
['val1']
>>> [k.name for k in HKCU.Software.MyTests.subkeys()]
['stuff']
>>> len(HKCU.Software.MyTests.stuff)
3
>>> del HKCU.Software.MyTests

Any other value assigned to a subkey will become the default value for that key (i.e. the value with name “”):

>>> HKCU.Software.MyTests = "dead parrot"
>>> HKCU.Software.MyTests[""].data
u'dead parrot'
>>> del HKCU.Software.MyTests

And that’s that - enjoy!