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

[Sriram Karra]

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.

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.


>
> > 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.



> >
> > 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.



> 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!


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.


> 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 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.