[BangPypers] What are you using for developing desktop GUIs?

Fri Sep 27 20:34:40 CEST 2013

I have spent 10+ years of Desktop app development using VC++/.NET, mostly
on Windows. After Windows XP SP 3 onwards, Microsoft changed the
application installation and execution architecture, specifically the
socket servers, firewall, administrator rights etc.

We have WCF Web Service (part of MS .NET framework), which was running on
TCP/IP, we have so much of trouble when users install application on their
machines.

Basic issues are listed here, which are difficult for common users to deal.

1. Anti-virus apps block the socket/outgoing emails/application altogether
2. Firewall blocks the binding to port, incoming/outgoing connections.
3. End user shall not have admin rights to install/run the server
applications that especially binds to socket server.
4. Socket port number could have been bind  by other process, so we get
port bind exceptions.

None of above are not part of our application, but affected by external
world. Situation is completely based on what user had before, what is there
right now, what he/she might have later.

On Windows, we use WCF Named Pipe binding now. No more socket related
issues. During installation, we install our server as Windows Service with
admin rights which uses named pipe (using GUID + some strong identity
options for naming pipe).

--

Krish

On Fri, Sep 27, 2013 at 10:20 PM, Dhananjay Nene
<dhananjay.nene at gmail.com>wrote:

> On Fri, Sep 27, 2013 at 10:04 PM, Sriram Karra <karra.etc at gmail.com>
> wrote:
> > On Fri, Sep 27, 2013 at 8:55 PM, Dhananjay Nene <
> dhananjay.nene at gmail.com>wrote:
> >
> >
> >>
> >> In most cases I find users want a installer. Basically just point and
> >> click. So if there is no installer where a user selects a install
> >> directory and presses a button called install (and perhaps a couple of
> >> app specific items), there's a huge support cost due to users being
> >> not able to install apps successfully. I presume what you mean by a
> >> standard python application, but if it means a user having to install
> >> python if not installed, create a virtualenv, run pip install, create
> >> desktop shortcuts to start / stop servers, in most cases it is very
> >> very unlikely to work with lay end users. (Much of this applies to
> >> desktop based apps as well).
> >>
> >
> >
> > None of that pip/virtualenv stuff is required. There are tools available
> > that can convert a python application into a native executable - py2exe
> for
> > windows, and py2app mac, for. e.g. Once you have the native, self
> contained
> > executables, they can be wrapped into a msi or dmg package like any other
> > native application.
> >
> Ok. I haven't tried them myself ever :( Though usually there's more
> required during installation (eg. where does the program get installed
> what directory should data go to etc. Not sure if these get addressed
> by these. Perhaps there are standard python ways to deal with all such
> issues that I am unaware of.
>
> > When I said the embedded webapp is like any other python application I
> > wanted to say that the above packaging options area available for a
> webapp
> > as well - because all the code is pure python and is completely self
> > contained. I hope that was clear.
> >
> It wasn't to me, but that could be my shortcoming.
> >
> >>
> >> > I have not done this. The invocation is explicitly on demand. It is
> >> trivial
> >> > to protect against multiple invocations of the program, and to
> support a
> >> > 'Exit Program' action on the front end that will shut down the web
> >> server.
> >>
> >> Ok. I've never tried this. Perhaps it is trivial. But shutting down a
> >> server even as the controller is processing a request may
> >> "potentially" be hard. Perhaps one could set a timeout to allow the
> >> request to complete and then trigger a shutdown.
> >>
> >
> >
> > You should definitely fire up the PRS program below, and look at how the
> > shutdown action is triggered and handled in the controller. My guess is
> you
> > will find it very straightforward.
> >
> Ok.
> >
> >
> >> >
> >> > It is as easy as any other program. To give you an example, take a
> look
> >> at
> >> > a sample: https://github.com/skarra/PRS
> >>
> >> Ok, I am not particularly familiar with how the windows integration
> >> works so am not able to quickly figure it out.
> >>
> >
> >
> > There is no windows integration of any sort here. If you are using python
> > on Windows already, just clone that repo and double click on the file
> > called prs.pyw -> that is all you need to start the program.
> >
> Haven't used windows in ages :(
> >
> >
> >> The difficulty is that the user may have multiple versions of python
> >> installed and/or his default version may not be compatible with the
> >> one you want. Plus virtualenv specific for your app will need to be
> >> configured.
> >>
> >
> >
> > As explained above, the py2exe / py2app type programs are able to make
> > completely self contained native executables.
> >
> >
> >>
> >> You did mention reusable code. Service integration, system tray
> >> integration etc. are all cross platform issues that are introduced
> >> when you install a web app on a desktop
> >
> >
> >
> > I do not know if there are any cross-platform python libraries that take
> > care of issues such as this. I will only say that the webapp approach to
> > cross-platform UI programming does not put you at any greater
> disadvantage
> > than using a UI toolkit. Remember the original topic was discussion on UI
> > toolkits!
> >
> My point was that service and system tray integration are usually not
> required for desktop apps. But if your webapp is going to be
> explicitly started and stopped by user, it may not be required by such
> webapps as well.
> >
> > You also open yourself up to cross browser portability issues. Also
> >> having to deal with older vs newer browsers (IE6??). Which if you were
> >> using a standard widget library wouldn't have worried you.
> >>
> >
> >
> > That is definitely very true. But in this day and age of html5
> boilerplate,
> > twitter bootstrap, jquery, etc. this particular problem can be considered
> > well under control.
> >
> >
> >>
> >> At the minimum you have an open port. You probably need to restrict
> >> traffic only from localhost.
> >
> >
> >
> > Yes, and this is done very easily, I am sure agree.
> Yes.
> >
> >
> >> In addition you need to worry about SQL
> >> injection, XSS, XSRF, and a bunch of other alphabet soup combinations.
> >>
> >
> >
> > I would image these are all non-issues if you reject all connections not
> > from localhost as discussed above?
> I am afraid not.
> >
> >
> > I don't mean to suggest it is wrong or inappropriate to use webapps as
> >> desktop apps. But just wanted to point out there are a whole bunch of
> >> counter issues as well that need to be dealt with.
> >>
> >
> >
> > Absolutely. It is definitely constructive and instructive to think about
> > all angles - even if just to understand the limits of a given approach.
> > Thank you for this conversation.
> The pleasure's mutual. I learnt a few things along the way.
>
> Dhananjay
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