Develop Reference

Trouble getting GIMP plugins to work (python attribute missing)

I'm trying to add some popular plugins to GIMP (version 2.99.10), but when I launch GIMP, I get errors like the following:
AttributeError: 'SuperResolution' object has no attribute 'set_translation_domain'
SuperResolution is a subclass of Gimp.PlugIn.
I've only installed GIMP recently, so I'm guessing there's some sort of path / scope issue that's causing python not to be able to see the inherited set_translation_domain attribute, but I don't exactly know what the problem would be.
Any ideas?

In superresolution.py replace this:
def do_query_procedures(self):
self.set_translation_domain(
"gimp30-python", Gio.file_new_for_path(Gimp.locale_directory())
)
return ["superresolution"]
To this:
def do_query_procedures(self):
return ["superresolution"]
def do_set_i18n(self, procname):
return True, 'gimp30-python', None
That happens because they changed how localization works in the recent builds of GIMP (2.99.10 - 2.99.13). Here is one of their internal plugins foggify to compare.

Why is format(str(var)) giving me an Attribute Error for my os.system

I'm trying to make a Python script that connects me to a VPN Server 'number' (with this number as a variable)
I wrote:
import os
VPNServer = 0
VPNServer += 1
os.system("networksetup -connectpppoeservice 'VPNServer {servernumber}'").format(servernumber = str(VPNServer))
print("→ Successfully connected to", "VPNServer", VPNServer)
But everytime I try to run it, the console gives me an AttributeError
AttributeError: 'int' object has no attribute 'format'
I don't understand it because I took the string version of the variable
If someone could help, it would be super cool
I'm on macOS and I'm using Python 3.8.1

In the snippet you provided, you write
os.system('<some string>').format(args)
You are making the format call on the return value of os.system, which happens to be an integer. This is identical to writing e.g.
5.format(args)
Since int objects have no attribute format, you get the AttributeError you described.
What you want to write is
os.system('<some string>'.format(args))
In this specific case, your snippet should resemble
os.system(
"networksetup -connectpppoeservice 'VPNServer {servernumber}'"
.format(servernumber=VPNServer)
)
Note that the str(VPNServer) call is superfluous, since format will autmatically call the __str__ method of the object provided.

Error when settingDBus property

I'm trying to set a property of a DBus Interface with Qt5.7.0.
This is the doc:
http://git.kernel.org/cgit/network/ofono/ofono.git/tree/doc/modem-api.txt
and I want to set the Powered property to true.
Here my code:
QDBusInterface *iface = new QDBusInterface("org.ofono", "/hfp/org/bluez/hci0/dev_xx_xx_xx_xx_xx_xx", "org.ofono.Modem", QDBusConnection::systemBus());
iface->call("SetProperty", "Powered", QVariant(true));
and this is the error:
QDBusError("org.freedesktop.DBus.Error.UnknownMethod", "Method "SetProperty" with signature "sb" on interface "org.ofono.Modem" doesn't exist")
The path comes from the GetModem method and it's correct.
Also, I tried the same with Python:
modem = dbus.Interface(bus.get_object('org.ofono', '/hfp/org/bluez/hci0/dev_xx_xx_xx_xx_xx_xx'), 'org.ofono.Modem')
modem.SetProperty('Powered', dbus.Boolean(1))
and it works fine! So the problem is definitely related to my Qt5 code.
How to better understand the error message? Is wrong my signature or it doesn't find the SetProperty method at all?

Heavily confused by win32api + COM and an answer from SO

From my other question here on SO, I asked how to retrieve the current playing song from Windows Media Player and Zune, I got an answer from a c++ dev who gave me an explanation of how I would do this for WMP.
However, I am no C++ dev, nor am I very experienced with the pywin32 library. And on-top of all that, the documentation on all this (especially concerning WMP) is horrible.
Therefor, I need your help understanding how I would do the following in Python.
Source
I have working code in C++ to print the name of media currently
playing in WMP. It's a simple console application (78 lines of code).
Steps:
1) implements a basic COM object implementing IUnknown, IOleClientSite, IServiceProvider and IWMPRemoteMediaServices. This is
straightforward (sort of, your mileage may vary) using the ATL
template CComObjectRootEx. The only methods needing (simple) code are
IServiceProvider::QueryService and
IWMPRemoteMediaServices::GetServiceType. All other methods may return
E_NOTIMPL
2) Instantiate the "WMPlayer.OCX" COM object (in my case, via CoCreateInstance)
3) Retrieve from the object an IOleObject interface pointer via QueryInterface
4) Instanciate an object from the class seen in 1) (I use the CComObject<>::CreateInstance template)
5) Use the SetClientSite method from the interface you got at 3), passing a pointer to your OleClientSite implementation.
6) During the SetClientSite call, WMP will callback you: fisrt asking for an IServiceProvider interface pointer, second calling the
QueryService method, asking for an IWMPRemoteMediaServices interface
pointer. Return your implementation of IWMPRemoteMediaServices and,
third, you will be called again via GetServiceType. You must then
return "Remote". You are now connected to the WMP running instance
7) Query the COM object for an IWMPMedia interface pointer
8) If 7) didn't gave NULL, read the the IWMPMedia::name property.
9) DONE
All the above was tested with VS2010 / Windows Seven, and with WMP
running (if there is no Media Player process running, just do
nothing).
I don't know if yoy can/want to implement COM interface and object in
Python. If you are interested by my C++ code, let me know. You could
use that code in a C++ DLL, and then call it from python.
I know a little bit about the win32api.
At the first step, I really don't know what to do, googling IOleClientSite results in the msdn documentation, it's an interface. However, that's where I get stuck already. I can't find anything (might just be my horrendous googling skills) on working with these things in Python.
The second step:
WMP = win32com.client.Dispatch("WMPlayer.OCX")
Alright, that's doable.
On to the third step. QueryInterface -
"regardless of the object you have, you can always call its QueryInterface() method to obtain a new interface, such as IStream."
source
However, not for me. As I understand his explanation, I think it means that every com object sort of "inherits" three methods from IUnknown, one of which is QueryInterface, however this does not seem the case since calling QueryInterface on my WMP object fails miserably. (Object has no attribute 'QueryInterface')
I could ramble on, but I believe you got the point, I have no idea how to work with this. Can anyone help me out with this one? Preferably with code examples, but resources/documentation is welcome too.

Almost final answser but CAN'T finish.
I seems that pythoncom can't be used to implement custom Interface without the help of a C++ module.
Here is an answser from Mark Hammon (Mon, 13 Jan 2003): How to create COM Servers with IID_IDTExtensibility2 interface
Sorry - you are SOL. To support arbitary interfaces, you need C++
support, in the form of an extension module. There is a new "Univgw"
that may help you out, but I dont know much about this
I am not able to find anything about that "Univgw" thing...
The comtypes python module is intended to resolve the problem, and I found links saying it does, but I can't make it works with my fresh new Python 3.3. It's Python 2.x code. comtypes seems outdated and unmaintained.
Step 1 OK for IOleClientSite and IServiceProvider, KO for IWMPRemoteMediaServices
Step 2, 3, 4 and 5 OK
Step 6, 7 and 8 can't be implemented without IWMPRemoteMediaServices :-(
disclaimer: complete newbie in Python, please don't yell
import pythoncom
import win32com.client as wc
from win32com.axcontrol import axcontrol
import win32com.server as ws
from win32com.server import util
from win32com.server.exception import COMException
import winerror
import pywintypes
# Windows Media Player Custom Interface IWMPRemoteMediaServices
IWMPRemoteMediaServices = pywintypes.IID("{CBB92747-741F-44FE-AB5B-F1A48F3B2A59}")
class OleClientSite:
_public_methods_ = [ 'SaveObject', 'GetMoniker', 'GetContainer', 'ShowObject', 'OnShowWindow', 'RequestNewObjectLayout', 'QueryService' ]
_com_interfaces_ = [ axcontrol.IID_IOleClientSite, pythoncom.IID_IServiceProvider ]
def SaveObject(self):
print("SaveObject")
raise COMException(hresult=winerror.E_NOTIMPL)
def GetMoniker(self, dwAssign, dwWhichMoniker):
print("GetMoniker ")
raise COMException(hresult=winerror.E_NOTIMPL)
def GetContainer(self):
print("GetContainer")
raise COMException(hresult=winerror.E_NOTIMPL)
def ShowObject(self):
print("ShowObject")
raise COMException(hresult=winerror.E_NOTIMPL)
def OnShowWindow(self, fShow):
print("ShowObject" + str(fShow))
raise COMException(hresult=winerror.E_NOTIMPL)
def RequestNewObjectLayout(self):
print("RequestNewObjectLayout")
raise COMException(hresult=winerror.E_NOTIMPL)
def QueryService(self, guidService, riid):
print("QueryService",guidService,riid)
if riid == IWMPRemoteMediaServices:
print("Known Requested IID, but can't implement!")
raise COMException(hresult=winerror.E_NOINTERFACE)
else:
print("Requested IID is not IWMPRemoteMediaServices" )
raise COMException(hresult=winerror.E_NOINTERFACE)
if __name__=='__main__':
wmp = wc.Dispatch("WMPlayer.OCX")
IOO = wmp._oleobj_.QueryInterface(axcontrol.IID_IOleObject)
pyOCS = OleClientSite()
comOCS = ws.util.wrap(pyOCS, axcontrol.IID_IOleClientSite)
IOO.SetClientSite(comOCS)

ClassNotFound exception when adding custom filter to OpenStack

I am trying to create a custom filter for OpenStack, using their FilterScheduler component. The documentation for the FilterScheduler is here: http://docs.openstack.org/developer/nova/devref/filter_scheduler.html#
Now, there is not much in the way of documentation for creating your own custom filter. Infact, the complete documentation is:
If you want to create your own filter you just need to inherit from BaseHostFilter and implement one method: host_passes. This method should return True if host passes the filter. It takes host_state (describes host) and filter_properties dictionary as the parameters.
As an example, nova.conf could contain the following scheduler-related settings:
--scheduler_driver=nova.scheduler.FilterScheduler
--scheduler_available_filters=nova.scheduler.filters.standard_filters
--scheduler_available_filters=myfilter.MyFilter
--scheduler_default_filters=RamFilter,ComputeFilter,MyFilter
I have created a custom "test_filter.py" -- it is very similar to "all_hosts_filter.py", which is the simplest standard filter.
Here it is in it's entirety:
from nova.scheduler import filters
from nova.openstack.common import log as logging
LOG = logging.getLogger(__name__)
class TestFilter(filters.BaseHostFilter):
"""NOOP host filter. Returns all hosts."""
def host_passes(self, host_state, filter_properties):
LOG.debug("COMING FROM: nova/scheduler/filters/test_filter.py")
return True
But when I put this file, "test_filter.py", in the nova/scheduler/filters folder and restart OpenStack I get the following exception:
CRITICAL nova [-] Class test_filter could not be found: 'module' object has no attribute 'test_filter'
It appears that OpenStack is registering and trying to import my new filter, but some error is occuring. For reference, this is what the releveant sections of my /etc/nova/nova.conf file looks like:
scheduler_available_filters=nova.scheduler.filters.all_filters
scheduler_available_filters=nova.scheduler.filters.test_filter.TestFilter
scheduler_default_filters=TestFilter,RamFilter,ComputeFilter
======
UPDATE: 15th April 2000 hours BST.
An update to this question, still struggling. After discussing the problem with boris-42 on the OpenStack IRC channel we have investigated a bit more:
Openstack-scheduler is run as service from /usr/bin/nova-scheduler
It then has an error:
"Inner Exception: 'module' object has no attribute 'test_filter' from (pid=32696) import_class /usr/lib/python2.7/dist-packages/nova/utils.py:78"
Which suggests it is using the /usr/lib/python2.7/dist-packages/nova/ folder for the source files of the installation.
Putting my custom "test_filter.py" into /usr/lib/python2.7/dist-packages/nova/scheduler/filters causes the error above.
However, on closer inspection it appears that all other files in the /usr/lib/python2.7/dist-packages/nova/scheduler/filters folder are actually links to the files in /usr/share/pyshared/nova/scheduler/filters
So I put my "test_filter.py" in /usr/share/pyshared/nova/scheduler/filters -- and then created a symbolic link in the original folder.
This results in exactly the same folder. As long as the file is either present or a link exists in the folder /usr/lib/python2.7/dist-packages/nova/scheduler/filters then the error occurs.
The nova.conf file has been updated as follows:
scheduler_available_filters=nova.scheduler.filters.TestFilter
scheduler_default_filters=TestFilter

I dont think you have to put your file in /usr/lib/python2.7/dist-packages/nova/scheduler/filters. You can put anywhere and make sure that path is in PYTHONPATH.
As metnion in example
If you want to create your own filter you just need to inherit from BaseHostFilter and implement one method: host_passes. This method should return True if host passes the filter. It takes host_state (describes host) and filter_properties dictionary as the parameters.
As an example, nova.conf could contain the following scheduler-related settings:
......
--scheduler_available_filters=myfilter.MyFilter
.......
You have to mention myfilet.MyFilter without nova.scheduler.filters.