adding browser capability to an existing python script - python

In essence I want to run existing python scripts through a web browser, display the text and plots(if any) and also keeping the ability to run them through the command line.
I am wondering is there any toolkit that can help me with the development.Also it would be nice if the toolkit does or allows JavaScript based interactive plots.
Thanks!
-Abhi

WSGI is designed for just this purpose - it provides an interface for a web server to initiate python scripts.
You probably don't want to work with WSGI in the raw. Flask is a straightforward, simple framework you might use for this.
The details of how to actually build a WSGI web server are well beyond the scope of a stackoverflow answer - you can find plenty of tutorial docs on Flask's website.

Related

How do I create a web application using Core Python without a framework?

I want to build an web application using python as a backend so, as I did not learned any of the web frameworks that are available for python I want to know is there any way to create backend for an app without frameworks.
While there is a discussion in the comments about the utility of frameworks, I am trying to answer the question at its face value.
WSGI
Python frameworks like Flask and Django both at the end are WSGI applications. WSGI (Web Service Gateway Interface) is a PEP specification which defines how the server and client must communicate. If I were to start from scratch, I would probably start with learning about WSGI and even try implementing a little ping-pong server with it. The read the docs page here https://wsgi.readthedocs.io/en/latest/learn.html lists a number of pages to learn about it.
Werkzeug
Once the WSGI specs are understood then one can attempt building a simple library that will wrap the core concepts into reusable functions and modules for easily writing an application. Here Werkzeug can be a good guide to make one understand the different aspects. https://www.palletsprojects.com/p/werkzeug/
Your own application
Based on the understanding of the WSGI spec and the Werkzueg library you can go on to write your applications either from scratch, or write a library like werkzueg yourself and then use it to write an application.
Finally reimplement the same app in Flask or Django to see what frameworks offer.
If it's something small for internal use you can use
https://docs.python.org/3/library/http.server.html

Dynamically updating web app to monitor progress of python script? Through Web.py perhaps?

I've got a python script that I want to build a locally-hosted web gui app for, so I can use the modern styling and tools available to web apps.
The scripts I'm running take a while to process, and I want to update the web app with visual updates, or at least something akin to what the console sees when using print() in python.
My initial hosting efforts have been based on this tutorial, and I tried out the methods in this answer to try and get data to update in a streamed fashion, but the pages only showed once the entire script was finished.
I'm wondering whether web.py could help me?
Any guidance, or even the right terms to google would be appreciated. Thanks.
--
Update: I've been reading up on node.js (something I've failed to do for years..) and, please correct me if I'm wrong, but it seems like it could be the answer. I'm even considering re-writing my original functions into node.js given the existence of this serial comms library

Extensible Local HTTP Server with Framework in Python

I'm trying to build a desktop application using Python. To make it able to be used on as many platforms as possible, I think web UI may be a good choice. This boils down to the problem of making a local HTTP server first. I did some survey and found that people are mainly talking about BaseHTTPServer and SimpleHTTPServer. For prototyping, subclassing them may suffice.
Besides pure prototyping, I also want to leave some room for extension to real service. That is, once mature, I'd like to move the codes to a real dedicated HTTP server, so that end users only need a browser to use it.
I say "extensible" in the following sense:
The code modification is as minimum as possible in the migration process.
I will focus on algorithm in the prototyping stage. I also want to leave some room for future front end designer.
It looks WSGI + Django is a widely mentioned combination. After some search, what I found is using WSGI in apache or nginx. Is it possible to use self-contained modules? i.e. wsgiref + Django, so that I can start everything just from one entry script. I don't want to bother potential first adopters by asking them install apache and configure it. It will be very good if you have sample codes or pointers for further reading.
I'm new to Python and web programming in Python. Thanks for your help. I just try to make sure I'm on the right track. My underlying algorithms is implemented in Python 2.7. So the UI solution had better also be in Python 2.7.
I think what you may want is Bottle. It is a web framework that only needs the standard library to be installed. It also has compatibility with many other production servers, as well as shipping with it's own development server. And if that isn't good enough, it is all in a single file, and has support with many different templating languages, as well as it's own built in templating language.
Check it out here: http://bottlepy.org/docs/dev/
As mentioned bottle is a good choice, I personally like Flask, which if I recall correctly is what bottle is based off of. Anyways there are three things that really make Flask a joy to use.
Blueprints - essentially an application architecture
Flask-Sijax - allows for comet technology
Celery - an asynchronous task queue/job queue based on distributed message passing
there are a lot of other plugins, including one for an admin interface that I haven't tried out yet but it looks promising, and it works with Python 2.7

cgi scripts with no server

My goal is to use to make it easy for non-programmers to execute a Python script with fairly complex options, on a single local machine that I have access to. I'd like to use the browser (specifically Safari on OS X) as a poor man's GUI. A short script would process the form data and then send it on to the main program(s).
I have some basic examples of python scripts run using the built-in Apache server, by clicking submit on a form whose html is th:
e.g. here. What I want to do now is do it without the server, just getting the form to invoke the script in the same directory. Do I have to learn javascript or ...? I'd be grateful for any leads you have. Thanks.
It doesn't make sense -- what a browser does when it submits a form by definition is to make a request to a web server.
If all that's going on is that you don't want to be running Apache, you could hook something simple up using the CGIHTTPServer class that's provided as part of the Python Standard library.
If you don't want a server process at all, and you're using a suitably modern browser, you may want to look at using HTML5 local storage, but that's not a Python solution.
Well, there always has to be some kind of "server" involved to communicate over HTTP. You could have a python script listening on port 80 on your machine, that in turn runs the scripts specified with the form's action attribute.
You won't get away without some sort of server, I'm afraid.
PS: There are already a couple of good minimalistic python HTTP servers that would do the trick. Just google for it.
Regards, aefxx
Pyjamas Desktop will allow you to deploy a browser-based desktop application.

What modules ought I to consider in Python if I wish to use CGI sessions?

Given that I know no web frameworks in Python and would like to keep it Very Simple at the moment (as I am Very Stupid), for what is a prototype of sketchy longevity, are there any streamlined, simple, "batteries-included" modules for this? (It is also too early in my Python career to evaluate frameworks, select one, and learn it.) I see a module named "Cookie," which could serve as a foundation, but nothing session-specific.
I'm familiar with the basic session concepts, having used them in classic ASP and gotten into the nuts-and-bolts of them in Perl, but I am not seeing a lot for Python. Beaker looks interesting, but then the documentation seems to require middleware with WSGI and I'm back to the frameworks problem.
I've found an old recipe on ActiveState for sessions, which could obviously use some buffing up. The information being held is not anything anyone would mind having been grabbed, so while I am normally quite security conscious, I would be willing to be a little bit more lax with this prototype.
Or is this a "roll-your-own" problem?
I will be using Python 2.6 on IIS 7.0.
I think the web2py (web framework) is easy enough for you. I think it is the simplest approach of making a website or webservice. It will be also easier, than to understand Cookie or the other modules of python related to web-things.
You can start a session, by just typing:
session.your_session_name = "blabla" # or whatever you want to store
To make a cookie, just look here.
In web2py you don't have to configure anything. Just download it and start web2py.py. (you must have python 2.6 < installed.) You can also find some examples and a web-slide.
The Python Cookie module does nothing more than to hold some values in a dictonary-like object, but I think you have to store it yourself on your harddisk.
CherryPy is worth looking into. Yes it is a framework, and yes it requires WSGI, but it is extremely lightweight compared to other more robust alternatives.
There is another question that was answered on SO that gives a brief example on how to manage sessions with CherryPy. As you can see it makes it very easy to get up and running quickly.
Lastly, here is a little document about setting up IIS for use with CherryPy.
WSGI is not a framework, nor does it require that you choose one -- it's THE standard way to run any Python web app framework on any Python-supporting web server, including a CGI one. If you have a WSGI application named app, and want to run it on CGI, see the docs and use wsgiref.handlers.CGIHandler().run(app), as the docs say.
So, you can perfectly well use Beaker via WSGI (on top of CGI) -- e.g., take the example in Beaker's docs and just add (the needed imports and) the run call above (using the wsgi_app object that example constructs, plus of course a session.save and as well needed as, again, the Beaker docs explain right afterwards).
Rich or heavy frameworks have their place but so do lightweight, flexible components like Beaker -- and WSGI middleware is a great way to leverage such components without requiring any "framework-y" arrangements, just good old WSGI (on top of CGI or anything else).
BTW, the best way to run WSGI on IIS might be isapi-wsgi (I can only say "might" because I have no IIS installation on which to test it;-). But as long as you code to WSGI (with any framework or with none at all), that will only be an optimization -- your application won't change (net of what handler's run or equivalent method you need to call;-) whether it's running on CGI, IIS via ISAPI, Google App Engine, or any other server-and-interface-thereto combination

Categories

Resources