Develop Reference

Building an EXE with a Flask server included

I'm attempting to build an application that runs locally on a user's computer. It takes inputs and displays information, so I thought a nice way to make it work would be to have a Flask server that handles web forms, etc, to gather user input, and to display database contents in tables.
The service works when I run the Flask development server, and everything is fine and dandy, but I want to compile the entire project into a single executable file.
My questions are as follows:
Is it possible for me to have the flask server automatically start up and open the portal page when I double-click the EXE
Assuming this is a feasible concept, how would I go about compiling the exe? A brief look through the pyinstaller documentation does not tell me how I would compile a folder (which in this case would be more of a Python package), which would be a necessary pre-requisite considering that Flask has static and template folders containing my HTML, CSS, and JS files, not to mention the fact that my file tree is built in a modular manner.
Am I approaching this the wrong way? Would it be better to build a "launcher" application that runs Flask as a Windows service (vis a vis this question) instead of attempting to have an all-in-one EXE?
For reference, my file tree looks something like this:
Application
|_static
|_templates
|_\templates\errors
|_\templates\forms
|_errors
|_database
|_\database\connections
|_\database\iohandlers
|_"__init__.py"
|_"app.py"
While doing research on this, I came across this answer but as my situation doesn't mesh with the model that the OP had laid out, I thought it would be pertinent and useful to ask another question.

Python program crashes when run through a Windows service

My client has provided me with a Python console application which performs some work and writes the result into a .txt file. My task is to write a Windows service which reads that particular .txt file and performs further actions.
I used C# on .NET to write the service. My solution contains 3 projects:
The logic layer project.
The Windows service layer project.
A test app layer project, used for debugging and other purposes.
Both the Windows service layer and test app layer are using the logic layer for core functionality. When I run the application through the test layer, everything works perfectly, but whenever I try to run the application through the service, the Python standalone application that the service launches doesn't write any output files. I could see that the Python app runs in the task manager, but there's no output anywhere. I believe the Python code is crashing but I couldn't get the exact reason.
I've tried the following ways to debug the issue:
Searched the Windows and System32 directories for any related output files, just to consider the possibility of the service having these directories as the default working directory.
Used absolute paths in the service code to make sure that the Python part is not writing output files to some unknown location.
Had the client implement passing the output directory to the Python code through command line arguments.
Wrote a mock console app in C# which writes a file, tried to call it through the service, but it worked fine and wrote the file as expected.
Suspected the standard IO could be causing the Python application to crash and thus used the standard IO in my mock program, but it worked without any issues.
Tried giving a long task to the Python code, which should've taken about 30 minutes to execute completely, but the Python script ran and closed immediately, which essentially is reliable proof of the theory that it crashes at some point.
Tried running the service with my unelevated Windows user instead of the Local System pseudouser.
Tried configuring the service to be able to interact with the desktop.
I am all out of ideas here. Any direction I should also search in?
Just a note, if that matters: I am using System.Diagnostics.Process to launch the Python script.

If it works from your test app, it sounds like a permissions issue. What security context / user is the windows service running as, and does that user have permission to write to the filesystem where you are expecting it? Have you tried using a full path to the output file to be sure where it is expected?
I'd be inclined to write a tiny python app that just saves "hello world" to a file, and get that to work from a windows service, then build up from there.

Thanks to the help from timhowarduk, I finally was able to get to the root cause of the problem. The python script was looking for a configuration file, and when it was running from the Windows Service, it was looking for that config file in System32.
All the windows services are run from System32.
The above caused the python script to search in System32 since it was running as part of the windows service. I guess I might just ask the client to edit the python script to read config from the windows service application directory.

Build definition for Django app in VSTS

I'm looking for a functional build definition for a Django 2.0.5 app in Visual Studio Team Services.
What I'm trying to do is deploying my Django application to Azure App Services trough CI/CD, and the process is running well (I mean, the files is being traspased to production), but, for some reason, my app doesn't starts and I'm getting a lot of errors. I guess I'm traspassing the wrong files, but I really don't know it.
Can someone please tell me what did you do to build a Django app with CI/CD in VSTS?
EDIT:
What I'm doing is use a default build definition for Python called "Python package", but customized. In one of the build steps, it calls to "setup.py" file. I created the file in the root folder of my repository, and I wrote the next code:
import os
import shutil
from distutils.dir_util import copy_tree
if not (os.path.exists('./dist')):
os.makedirs('dist')
else:
shutil.rmtree('./dist')
copy_tree(".", "./dist")
Ok, I know the code is ugly, and I need to write it in a better way, but is functional and it copy the entire project structure into the "./dist" directory. Later, the release proccess takes all these files and copy it to production environment. All this works Ok, but my app never starts. When I try to navigate my url, I receive a 404 error, and can't use any of the project routes.
Hope it helps, if not, I will put all the necessary details, thank's again.

Finally I found the problem. I didn't traspased the environment folder, and I has missed web.config file too.
Uploading the env folder and the web.config file fix the application.
ref: https://github.com/azureappserviceoss/djangoapp

Python PY files do not reflect changes

I have experience with PHP but now have to manage a python application. It is already developed and running on live server. On live server we have beta.domain.com as well. which has its own copy of same source, other than the main domain application.
Now, when we print something within template it effects but before that, following MVC, if we try to print or use sys.exit() in manage.py or later imported "settings.py" or then views.py, nothing effects these files at all. After any change in just mentioned files, Website still renders everything and display related template.
Another thing that if even we remove
return render_to_response('home.html', RequestContext(request, context))
inside the views.py for testing, nothing effects and website still gets rendered with template.
Do I need to think that if website code is already hosted then in order to have changes to reflect new one in the code in any file (.py), needs to be reinitialized by executing any project related file?
I am not sure how python code needs to be updated at all, any quick help is much appreciated.

Anytime you change your code, you need to restart Apache server.
<path to apache>/bin/apachectl restart
The python interpreter of the process has already loaded your python modules in previous web requests. And once the module is loaded, it is stored in memory. Next time when a request comes, the Python interpreter will simply use the version of the module that is already loaded in memory. So your changed code will not be picked up.

Please, please, please don't try and edit files on your live server. You're only going to get yourself into terrible difficulties. Use a local copy for development, preferably cloned via a version control system, and deploy at regular intervals rather than on every change.
To answer your question, you usually need to restart the WSGI process in order to see Python code changes. An easy way to do this is to touch the .wsgi file, at which point mod_wsgi will detect that it has changed, and reload everything. Otherwise you can simply reload Apache.
Unfortunately I don't understand your references to manage.py or sys.exit.

The solution is excatly restarting the apache server as answered by Sudipta .Each time the py files are interpretted .pvc files are created for each corresponding .py files.When the Apache server is restarted all the python source files are interprretted again and new .pvc files are generated and only these files will run till the apache restarts again.

Web2Py Working Directory

Well I want to use WEb2Py because it's pretty nice..
I just need to change the working directory to the directory where all my modules/libraries/apps are so i can use them. I want to be able to import my real program when I use the web2py interface/applications. I need to do this instead of putting all my apps and stuff inside the Web2Py folder... I'm trying to give my program a web frontend without putting the program in the Web2Py folder.. Sorry if this is hard to understand .

In any multi-threaded Python program (and not only Python) you should not use os.chdir and you should not change sys.path when you have more than one thread running. It is not safe because it affects other threads. Moreover you should not sys.path.append() in a loop because it may explode.
All web frameworks are multi-threaded and requests are executed in a loop. Some web frameworks do not allow you to install/un-install applications without restarting the web server and therefore IF os.chdir/sys.path.append are only executed at startup then there is no problem.
In web2py we want to be able to install/uninstall applications without restarting the web server. We want apps to be very dynamical (for example define models based on information provided with the http request). We want each app to have its own models folder and we want complete separation between apps so that if two apps need to different versions of the same module, they do not conflict with each other, so we provide APIs to do so (request.folder, local_import).
You can still use the normal os.chdir and sys.path.append but you should do it outside threads (and this is not a web2py specific issue). You can use import anywhere you like as you would in any other Python program.
I strongly suggest moving this discussion to the web2py mailing list.

os.chdir lets you change the OS's working directory, but for your purposes (enabling imports of a bunch of modules &c which are constrained to live in some strange place) it seems better to add the needed directories to sys.path instead.

I had to do this very thing. I have few modules that I wanted to use from my controllers. If you want to be able to use the code that resides in the modules directory in the controller, you can use:
# use this in your controller code
impname = local_import('module_in_modules', reload=True)
# reload true will ensure that it will re load whenever
# there are changes to the module
Jay