I am looking for a pure Javascript/Python upload example, that uses server polling instead of client-side SWF to display upload progress (like the one on rapidshare.com for example)
Currently, website is running on the standalone wsgi server included with Werkzeug framework, but may be moved to mod_wsgi if the load increases.
I've tried the gp.fileupload middleware, but can't get it to work. Examples on their website wont work either :|
Website already uses Glow library for other misc client-side stuff, but there is no specific upload-related functionality in it.
If you don't have support on the web side to track the size of the temporary file (or in-memory buffer) of the uploading data as it arrives, I don't know how you'll do this. Some of the popular web servers have special support for this, mostly experimental, but it's not widely supported and what you're trying to do is pretty awkward in general. I've researched this recently and it's pretty poorly supported all around.
Related
I got 6 real-time videos which are inference output from heavy deep learning calculation from python, and I've tried to display them to PyQt that lots of threading issues with ugly GUI!!. So, I want to use a framework only to display well and fancy GUI! There seem lots of frameworks based on my google search, and I have no idea
which one is the best for my current project among Node js, Django, and Flask!
I need to display 6 real-time videos with 10~15 FPS.
Communicating well with python.
Easy to build GUI, I have some features like logging, displaying real-time graph(optional)
For video streaming, you will require to setup a socket URL for listening to incoming packet. Definitely, you can dedicate a server just for this to handle high amount of traffic.
Now, as such it dependents on your application, if you are just going to use it for streaming then Flask will do, it is lightweight. On the other hand, Django and NodeJS provides ready made function for socket programming and they are very useful.
I would say it doesn't really matter much as Django would be good because of its pre built features... Plus data transfer is very reliable in django along with your expertise in python, django is preferred. NodeJs would be easier to implement tho. Really prefers upon you, but both django and nodeJs works pretty well.
Sorry, no idea on flask
My opinion - flask faster development, node - better efficiency, some thoughts why are explained here: https://hinty.io/ivictbor/flask-vs-node/
Here's the setup: On a single-board computer with a very rudimentary linux I'm running a Django app. This app is, when a button is pressed or as a response to the data described below, supposed to call either a function from a library written in C, or a compiled C program, to write data to system memory at a specified address, poke/peek like. (Python doesn't seem to be able to do that natively).
The Django app should also display data, continuously, which is being read from the memory from the same library / program.
My question now is how to even begin with setting up the scenario described above. Is this even possible with a web app? Is a Django or more fundamentally any web framework even the right approach here? I'm at a bit of a loss here, since I've spent quite a few hours now trying to figure out how to do this while not getting the most basic starting point...
Disclaimer: I'm pretty new to the entire web framework thing, and more importantly web development in general, so sorry if this is a bad question as in, I could have easily found information on this topic online, but I couldn't really find a good starting point on this.
I wanted to add a comment but not enough space... anyway
You can write a native extension in C for Python that could do what you need, check this.
Now for the fact of displaying data continuously this is kind of vague, if this C library is switching this hypothetical address, very often and very fast you have to update a browser client as fast as possible.
I think websockets would do the trick but they are js related, so I think NodeJs would be a better candidate for the server side of your application instead of Django.
If you want to stick to Django you can also expose an URL with the generated address value and have a webpage continuously (with a little Interval) checking that URL using a simple ajax call, kind of ugly and inefficient but would work.
Anyway IMHO your best bet is for websockets because with them you have a fullduplex communication between client and server.
Good Luck with your project.
Info:
Websockets in Django with socket.io
Nodejs socket.io
I'm trying to learn web programming in python, and have the following project in mind: mine the yahoo finance api for instrument data, and display it in real time, as well as plot charts based on instrument data.
I already did something similar using wxpython, and I'm interested in how I would accomplish this in a web application.
My first thought was to use django and matplotlib on the server, and have the client request updated chart images through jquery at a certain time interval, but after a bit of research I came upon libraries like twisted and tornado...and now I'm confused. Would they work better for this web app than django ?
After the above rambling, my question is: what library should I use for writing the web app i have in mind ? I'm also thinking that I should abandon matplotlib, and generate the chart on client side, but I'm not sure what javascript library would allow me to do that, if any.
Few tips:
1/ Do not plot your data at backend . Instead use the browsers to generate charts.I would recommend
using jqplot, or highcharts.
2/ Yes, you can use tornado or twisted instead of django, as they are asynchronous servers, and would provide faster handling of requests.
3/ You should create a REST interface of your application, with server side only sending JSON data, and do all the UI templating and charting on client side.
4/ Backbone.js (recommended, but you can use some other MVC framework), would also prove to be helpful if your app grows too complex.
I'm working on a tracking proxy (for want of a better term) written in Python. It's a simple http (wsgi) application that will run on one (maybe more) server and accepts event data from a desktop client. This service would then forward the tracking data on to some actual tracking platform (DeskMetrics, MixPanel, Google Analytics) so that we don't have to deal with the slicing and dicing of data.
The reason for this implementation is that it's much easier and faster to make changes to a server process that we control rather than having to ensure every client in the wild gets updated if the tracking backend changes in some way.
I've been looking up info on the various options and I was hoping somebody here would have some good advice from their own experiences. Ideally we'd be able to use Google Analytics as it's free for any amount of usage but paid options are fine.
My only real requirement is either a good Python library or a well documented api that I can write a wrapper for (this seems somewhat lacking in GA when it comes to triggering events through any method other than their js or other provided libs).
N.B. We're not really tracking server code so something like NewRelic isn't appropriate, we're just decoupling a desktop application from the specifics of the tracking backend.
We ran into this same problem a bunch of times, we ended up building a suite of server-side analytics libraries to make this easier.
Segment.io has libraries for Python, Ruby, Java, Node, .NET and PHP that abstract the APIs for Mixpanel, KISSmetrics, Google Analytics and a bunch of other analytics services.
You could integrate the Python library once, and then send your data wherever you want. The data is proxied through Segment.io's hosted service. Hopefully this cleans up the mess of integrating a bunch of libraries, each with slightly different APIs. (The service is free for the first million events.)
Have you tried anything below?
The Google Data APIs Python Client Library has source specific to analytics
http://code.google.com/p/gdata-python-client/
http://code.google.com/p/gdata-python-client/source/browse/#hg%2Fsamples%2Fanalytics
https://developers.google.com/gdata/articles/python_client_lib
You might be able to borrow from these sources as well;
Google has something they are working on for mobile and source is available in PHP, JSP, ASP.net and Perl: https://developers.google.com/analytics/devguides/collection/other/mobileWebsites
I also came accross this in PHP http://code.google.com/p/php-ga/
As for others:
KissMetrics: http://support.kissmetrics.com/apis/python
MixPanel: https://mixpanel.com/docs/integration-libraries/python
DeskMetrics: don't seem to have python, http://docs.deskmetrics.com/index.html
Sorry I cannot provide information based off extensive experience with anything python related other then providing a few of these resources. I would be interested to see what you come up with.
Disclaimer: I'm not very familiar with any of the things mentioned in the question title.
Would it be possible to use a browser control (like Webkit) as a frontend for a WSGI app (using a framework like Flask) without starting a local WSGI server?
Basically the requests and responses are managed by a middle layer between the HTML UI and the WSGI backend. A certain URI could mean "Local", for instance "local://" or something similar, and will be routed to the embedded WSGI app with all the original headers etc.
You will lose any features that a normal WSGI server provides unless you implement it yourself or somehow embed a server that is also usable via an API instead of real HTTP requests.
Now that I think of it, this is the only real requirement: A WSGI server that is callable via an API and not just real HTTP requests.
I know the usefulness of this is questionable (and maybe doesn't even make sense). My question is whether this is at all possible?
EDIT: Here's another way of putting it:
I want a single codebase to be both a web app and a desktop app, using an HTML frontend and a Python backend. I don't want to run a server on any port for the desktop app. What's the easiest way to achieve this?
It is in theory possible to write your own WSGI container that implements a full API and adapts that to WSGI. flup might bring some inspiration.
Earlier today I saw exactly what you're asking for -- a way to call WSGI through an API without actually connecting over the network. However, it shouldn't be that hard.
On a side note, you might want to look at PySide, of particular interest to you may be the ability to bind python elements to DOM events, so if you're just looking to trigger python code that's an even shorter route.
If you give some more detail on what you're hoping to achieve we might be able to dial it in for you.
Reviving this, since we're facing the same problem and are about to scale things up from a single view/widget to the whole app.
What I did was to simply set the base URL to something where I serve static content, and from a QRC file that's easy:
html = jinjatemplate.render(...)
self._mainFrame.setHtml(html.decode('utf-8'), Qt.QUrl('qrc:///Orsync/html/'))
For the communication, our HTML uses AJAX over jQuery for most things. You could wrap that in a layer that either does $.post(...) or api.post(...) like this:
self._mainFrame.addToJavaScriptWindowObject('api', self._webapi)
You'd need to decode the URL and create a request object yourself, but maybe that's not too hard to do? We use very few URLs currently (who are mapped directly to python objects/functions) so it's easy to do the mapping ourselves.
Data that goes back is just sent using QMainFrame.evaluateJavaScript(...), either as a direct Qt call or as a bunch of code lines fetched using $.getScript(...) (which just evaluates the code received).
I'm currently rebuilding things a bit using CherryPy, and it maps urls -> Python objects straight off, so I'm hoping there's something to be gained by that.
Otherwise, I would wish one could run QWebKit over named pipes or something similarly localized and not a tcp-socket. :)