Distributing a local Flask app - python

I've made a simple Flask app which is essentially a wrapper around sqlite3. It basically runs the dev server locally and you can access the interface from a web browser. At present, it functions exactly as it should.
I need to run it on a computer operated by someone with less-than-advanced computing skills. I could install Python on the computer, and then run my .py file, but I am uncomfortable with the files involved being "out in the open". Is there a way I can put this app into an executable file? I've attempted to use both py2exe and cx_freeze, but both of those raised an ImportError on "image". I also tried zipping the file (__main__.py and all that) but was greeted with 500 errors attempting to run the file (I am assuming that the file couldn't access the templates for some reason.)
How can I deploy this Flask app as an executable?

Host it.
Since you created it in Flask, and its a web app - hosting it should be trivial. Dump it on any of the PaaS providers like Heroku, Google App Engine, OpenShift or spin up a micro instance on EC2 and host it there.
Creating an executable is not the solution.

Why distribute it at all? If the user you want to use it is on the same local network as the Flask application, just give them the IP address and they can access it via a browser just as you are doing, and no access to the source code either!

Related

make flask application work for certain perio similar to trail software

I'm currently developing flask application for a client and i want to give him/her to test it in there local machine. Issue is that i don't have internet connect or remote access in their system so I'm forced to add all source code i did to their system. i want to know is there a way i can give the client flask application without providing him/her with source code.
My objective is to make source code hidden of flask application whether it by executable file or have 30days for testing and after 30days application will automatically be deleted or disabled from their system it similar how trial application work.
If anyone can guide me into how can i make source code of flask hidden from client when i don't have any access to PC or internet that flask application is installed in

How can I call a python script from an asp.net Azure app service?

I have an existing .NET Core / asp.net app service hosted on Azure. I need to call (on demand) a python script to return data based on custom user input.
It does not appear that I can use IronPython, since I need python modules that are built in CPython, which unfortunately aren't supported by IronPython.
The two options I see are:
I might be able to install the right python version and libraries on the app service and call it from the .NET code. This seems like it might be deprecated: https://learn.microsoft.com/en-us/visualstudio/python/publishing-python-web-applications-to-azure-from-visual-studio?view=vs-2017
I can create a whole new and separate app service for just the python script and call it as a REST API on demand from the .NET app service. This seems like overkill, and introduces the problem of opening up a whole new service publicly, which I don't want to do. This also appears to have the limitation that Flask isn't mean for production, so hosting many calls at once is not really workable. https://learn.microsoft.com/en-us/visualstudio/python/publish-to-app-service-windows?view=vs-2017
What is the best way to call a python script on demand from .NET app service on Azure?
Per my experience, there are two ways to call a Python script in C# without IronPython.
Directly use System.Diagnostics.Process in C# to run a command as same as the SO thread Run Command Prompt Commands to get the result via parse the content of the process standard output. Simply to do it, you can use py2exe to wrap a Python script as a .exe file to avoid for installing Python modules and setting environment variables on Azure App Service. However, considering for concurrency, it's not a good idea for performance.
The second option as you said is to deploy a Python script as a REST API in the same instance of Azure Web App. You can follow the blog Deploying multiple virtual directories to a single Azure Website to deploy a flask app with your Python script as a child project via Visual Studio with PTVS to expose an API url like https://<your web app name>.azurewebsites.net/pyapi which can be called from your ASP.NET via HttpClient. I tried this solution, it works.
Note: Due to the restriction of Azure Web App sandbox for Local Address Requests, you have to use <your web app name>.azurewebsites.net as hostname, neither localhost or 127.0.0.1.

Flask app doesn't builds on MS Azure cloud

I want to deploy my flask web application on Azure cloud. In Deployment options, I have selected GitHub as source destination for my flask code. after doing the configuration test successfully, the init.py file now starts building;
Now when I go to my application link, it shows me this;
Now at this point, I went back to my deployment options, it says Building failed;
the log generated for this building failed can be seen in the first picture. All the tests has passed except the last one "Performance test". Have anyone encountered the same issue before ? what can be the reason for that ?
I am running the application on localhost # port 8000.
from flask import Flask
app = Flask(__name__)
#app.route("/")
def hello():
return "Hello World!"
if __name__ == "__main__":
app.run()
Do I need to run it on another IP ?
You cannot listen on port 8000 in Web Apps. Only port 80 or 443. You'll need to read the port number from the environment, to know what to listen on.
If you created the Azure Webapp using the Flask tool, the default app is called FlaskWebProject1. If your app has a different name, you need to modify web.config in your wwwroot folder to reflect the correct app name.
Then redeploy using the Azure portal or change it in your GIT and push again.
Based on your 500 error, I think some python packages are not installed correctly.
To check your code is working correctly in naive manner, do as follows.
If you are developing on Windows machine, copy all of your site-packages files in development machine to WebApp /site/wwwroot/env/Lib/site-packages folder.
Hit Restart in Azure Portal and F5 in browser.
If it works, your deployment process might have a problem. Mainly it is caused by library installation.
First, check you have requirements.txt at the root folder. This documentation describes some considerations to load Flask on Azure WebApp. Of course, it would be really helpful to read the documentation from the first line carefully.
Second, login WebApp via FTP and check the package is installed correctly. You can see /pip folder has pip.log file, and /site/wwwroot/env/Lib/site-packages folder has its libraries.
For some libraries which you might require more than simple hello world app, you may have to push x86 .whl files along with python codes as they are not installed correctly in x86 environment.
Additionally, in order to show internal error to outside, consider to apply this option during development (not for production).

Django: Push app from local server to production server via FTP

This is a bit embarassing, but I'm a Django noob and I couldn't find a simple solution to this:
I have written a Django app in a local VM that I now want to deploy to a "production" server. App works like a charm locally.
Now my IT colleague has set up the server with Django and that also works fine. I can open it via the Web and I get the usual "Congratulations on your first Django-powered page". I can also log into the admin interface. The project has been created.
This is a very low-key mini project and I'm not too familiar with git, so we've decided to just push files via FTP. (And I want to stick with that if at all possible.) So I uploaded the app folder into the project folder and also adjusted the project's settings.py and urls.py.
However, nothing seems to be happening on the server's end. The welcome page is the same, the app does not show up in the admin interface and the URLs won't be resolved as hoped.
Any suggestions what I should have done / done differently?
You need to restart apache or whatever is running your django project. Your changes to py files are cached when you first load your server config (settings).
Any suggestions what I should have done / done differently?
You should be using git/jenkins/deployment techniques, I know you said you've decided not to use it but you're going to be missing out on important things like being able to keep track of changes and unit testing

Running a Python app on a remote server and displaying the output files

I have a Python 2.7 script at https://github.com/jhsu802701/dopplervalueinvesting . When I run the screen.py script locally, the end result is a new screen-output sub-directory (within the root directory) and a results.csv file within it.
What I'm trying to do is put this script on a remote server, run this screen.py script every night, and make the results.csv file publicly readable.
I've tried to do this on Google App Engine, but I can't get it to work. The Google App Engine tutorial revolves around trying to dynamically create a web site, and I haven't been able to figure out how to make anything other than an index.html file in the root directory work. HOW DO I MAKE OTHER FILES PUBLICLY READABLE?
Is Google App Engine the way to go, or am I barking up the wrong tree? I understand that another route is using WebFaction, a web hosting provider that offers a whole Linux system. (Running my app on my current web host, MDDHosting, is not an option because lxml is not available without a much more costly VPS.)
In summary, my questions are:
How do I run my Python script in Google App Engine and make the output results.csv file publicly available?
If Google App Engine isn't the solution for me, should I use WebFaction? (I already tried Heroku, and it didn't work for me.)
What are my other options?
I'm willing to pay for a solution, but only if I get web hosting as well. (I'm not willing to pay for MDDHosting for my dopplervalueinvesting.com web site AND another host for running my script.)
I think GAE should be good for what you want, but you may need to work differently because, as a comment pointed out, you can't write to the file system but have to use the datastore instead.
So you need in your app.yaml list of handlers, something like
- url: /results.csv
script: deliver_results_file.py
- url: /screen
login: admin
script: screen.py
screen.py needs to save the results to the datastore in some convenient format. deliver_results_file.py then queries the datastore, and if the results are not already in CSV format then it converts them accordingly. It then writes the formatted data directly to the output (usually using self.response.out.write within a webapp request handler) as if it was a dynamically generated webpage.
Finally you want to schedule it to run once a night - I believe this is possible using cron jobs.

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