I'm involve in a new proyect, let explain it briefly.
We have an application server, this server can be interfaces with other systems using udp (this is a design policy, I can change it).
Now we need a web app to collect the information sended by the application servers to show some reports and send back some configuration when we need.
We are very interested in Django with Twisted (or Hendrix), we are very new in python world, I surf in Internet for days and so far I undersand some concepts but I mess about how to start with a proof of concept, so I'm here.
I need an example or guide about how to start, our idea is simple for this proof of concept.
An Application server send some data over udp.
A twisted/django app receive that info and save it in a database table.
A django web page read the database table and show a report. I don't know if the web page need to run on twisted or not.
Please, I read a lot of post for days and I'm lost about how to start.
Thank you a lot in advance.
Best Regards.
Learn each part of your stack one-by-one. Start by following a Django tutorial, then once you're comfortable with Django run the app using Hendrix instead of Django's manage.py, finally add your UDP tasks via Twisted from Hendrix. Lucky for you all the projects you've mentioned have good communities and documentation. You don't have to get everything working perfectly, just get some working pieces.
Write some code, then when you have some running code and you get stuck somewhere, hop back onto Stackoverflow and ask your specific questions.
Update
As it so happens, there's a video which shows how to integrate Django + Hendrix. Give it a shot and tell us how it goes.
Related
I am new to full stack development, and having an issue with a web application I'm working on for my employer. I was tasked with creating a fairly simple application that we can scale over time. For now all that it needs to do is take data from one of our databases, and pass it to a front end application. Using this front-end app our workers should be able to double check the information passed in, and make sure it has been properly translated to a new format. After it is translated I want to send an HTTP POST request to our new systems back-end and have it add this new data via the REST API. Essentially it's an application that was used for practice to get me more acquainted with full stack development while making an effective tool to transfer mass data from one system to another. I can't seem to figure out how to set up something in ember.js to send that POST request to somewhere other than my back-end though.
I believe after re-reading the page on the ember.js site I found my answer. Sorry for posting a question that was already answered elsewhere. It was asked after a while of googling and not finding what sounded right. Just needed a day to let my brain reset I guess. In any case, if somebody else stumbles upon this post and (like me) wasn't comprehending at the time, the answer lies here: https://guides.emberjs.com/v1.10.0/models/connecting-to-an-http-server/
You simply create a new adapter with the host you want to send requests to. Then you can create a new model in my case to serialize the data in a way the host will understand what you're trying to transfer to it. This will allow for data migration between sources like I desired. Sorry again for the unnecessary post, but hopefully it helps someone else in the future.
I am building a dashboard that will monitor production data, and am able to access this data via web services. The data changes every 1 minute, so I would like to have a page with 4 charts/gauges (the number of systems I am monitoring) that would get the data pushed to them with a successive web service call.
Can anyone suggest a good charting kit that would work well with C#? And would SignalR be a good fit here do you think? I have read that node.js and socket.io are options, but I have no experience with node yet. I would like something along the lines of DevExpress. Perhaps jquery and something on the front end works here as well? Thanks!
For such a dashboard SignalR is definitely a good fit if you already work with .NET and ASP.NET. For a web dashboard in particular, a good graphic library is Raphael, which is open source and pure JavaScript. It's simple and straight to the point, but often less is more. You can build interesting kinds of charts with it.
This project is maybe interesting for you as a sample of those 2 technologies together. If you press the skulls to raise errors, they will be triggered on a backend simulator and pushed to the dashboard using SignalR. You will notice a piechart graph there, which is done using Raphael and updates live when new errors are received.
The code of the project is here, it's a bit complex but maybe you want to have a look anyway. It's based on SignalR 1.x, but overall concepts are still the same.
Please excuse the noobiness of my question. I am mostly searching here for some directions and buzzwords to start digging from.
I spent some time developing an application in Python
Basically, it takes a bunch of images and creates a video out of it.
It i quite simple, and uses only a few libraries (opencv and nunmpy mostly).
I designed a small gui in gtk, but I think that it would be a good idea to offer the service over the web.
I think I could reuse some of my core and design a front end that people could access in their browser.
I only need a few data to get it running (images, an email)
The thing is my web dev skills are really close to 0, and I don't exactly know where to start from .
I don't plan on having hundreds of people a day on the platform.
People would connect, feed me with the data (link to a dropbox folder, google drive, whatever) and I would send them a message where it's finished.
If you could provide me with some names or links so that I could touch the field, I'd be really glad.
CGI is a fine option, but if you already have Python experience Django is definitely worth checking out (it falls in the category of rhooligan's #3 except it uses Python!). Django completely takes care of all of the database backend details for you, which is a benefit over simple CGI. It also provides easy-to-use pre-defined classes for handling file uploads, images, etc. It also has a great tutorial that will get you up and running. Just be careful about whether you're using version 1.3, 1.4, or the latest dev version, because some aspects of the framework have changed fairly quickly. Make sure that you're always looking at the right version of the docs.
Another handy service to keep in mind for doing something like image processing through a web app is a hosted cloud computing service provider like PiCloud. Unless you already have a private web server with lots of memory and processing power, these cloud services that charge by the ms are really cool. They also give you 1000s of cores which could allow you to do lot's of concurrent processing. They provide a nice Python API, and it has numpy and opencv pre-installed in both v2.6 and v2.7. (They use PyOpenCV, but you also have root access to install anything you want, so you can set up the "cv2" interface if that's what you're using--actually I just looked at your GitHub and it looks like you're using the old "cv" interface. You can also install any application you want on PiCloud--it doesn't have to be Python.)
You could start by looking into the Python CGI module and see if it will work for you. Then you'll need to do the following steps:
Decide on a webserver and install it, Apache is probably a good starting point.
Design the UI. Wireframe things out on paper paper. Figure out how you'd ideally want the users to go through your site and what you want on each page/view.
Your decision in #2 drives all the decisions from this point out. These days, most web applications are a combination of Web 1.0 and JSON/REST "services" (there's a couple of buzzwords for ya!). JQuery is a popular and widely used JavaScript library for developing the front end of your site. That would be another thing to look at. JQuery is completely independent from the back end and can be used with any type of back end (PHP, Ruby, Perl, .NET, etc)
I am relatively new to Django and this is a more general 'concept' question.
For a client I need to construct an expansive database holding data returned from a series of questionnaires as well as some basic biological data. The idea is to move away from the traditional tools (i.e. Microsoft Access) and manage the data in a mysql database using a basic CRUD interface. Initially the project doesn't need to live on the web, but the next phase will to be to have a centralized db with login and admin page.
I have started building the db with Django models which is great, and I want to use the Django admin for the management of the data.
My question is: Is this a good use of Django? Is there anything I should consider before relying on django for the whole process? And is it advisable to us the Django runserver for db admin on a client's local machine (before we get to the web phase).
Any advice would be much appreciated.
Actually, your description sounds exactly like the sort of thing for which Django is an ideal solution. It sounds more complex and customized than a CMS, and if it's as straightforward as your description then the ORM is definitely a good tool for this. Then again, this sounds exactly like an appserver-ready problem, so Rails, Express for Node.js, or even ChicagoBoss (if you're brave) would be good platforms for this kind of application.
And sure, Django is solid enough you can run it with the test server for local clients before you go whole-hog and run the thing on the web. For that, though, I recommend Apache/mod_wsgi, and if you're going to be fault tolerant there are diamond architectures (one front end proxy with monitoring failover, two or more appserver machines, one database with hot spare) and more complex (see: sharding) architectural layouts you can approach later.
If you're going to run it in a client's local setting, and you're not running Windows, I recommend looking into the screen program. It will allow you to detach the running job into the background while making diagnostics accessible in an ongoing fashion.
is there someone who has expirience in hosting django applications on ep.io?
Waht are the pros/cons on it?
I'm currently using ep.io, I'm still in development with my app but I have an app deployed and running.
When you use a service like this you go into it knowing that it isn't going to be the perfect solution for every case. Knowing the pros and cons before hand will help set your expectations so that you aren't disappointed later on.
ep.io is still very young and I believe still in beta, and isn't available to the general public. To be totally fair to them, it is still a work in progress and some of these pros and cons may change as they roll out new features. I will try and come back and update this post as the new versions become available, and my experience with the service continues.
So far I am really pleased with what they have, they took the most annoying part of developing an application and made it better. If you have a simple blog app, it should be a breeze to deploy it, and probably not cost that much to host.
Pros:
Server Management: You don't have to worry about your server setup at all, it handles everything for you. With a VPS, you would need to worry about making sure the server is up to date with security patches, and all that fun stuff, with this, you don't worry about anything, they take care of all that for you.
deployment: It makes deploying an app and having it up and running really quickly. deploying a new version of an app is a piece of cake, I just need to run one maybe two commands, and it handles everything for me.
Pricing: you are only charged for what you use, so if you have a very low traffic website, it might not cost you anything at all.
Scaling: They handle scaling and load balancing for you out of the box, no need for you to worry about that. You still need to write your application so that it can scale efficiently, but if you do, they will handle the rest.
Background tasks: They have support for cronjobs as well as background workers using celery.
Customer support: I had a few questions, sent them an email, and had an answer really fast, they have been great, so much better then I would have expected. If you run your own VPS, you really don't have anyone to talk to, so this is a major plus.
Cons:
DB access: You don't have direct access to the database, you can get to the psql shell, but you can't connect an external client gui. This makes doing somethings a little more difficult or slow. But you can still use the django admin or fixtures to do a lot of things.
Limited services available: It currently only supports Postgresql and redis, so if you want to use MySQL, memcached, mongodb,etc you are out of luck.
low level c libs: You can't install any dependencies that you want, similar to google app engine, they have some of the common c libs installed already, and if you want something different that isn't already installed you will need to contact them to get it added. http://www.ep.io/docs/runtime/#python-libraries
email: You can't send or recieve email, which means you will need to depend on a 3rd party for that, which is probably good practice anyway, but it just means more money.
file system: You have a more limited file system available to you, and because of the distributed nature of the system you will need to be very careful when working from files. You can't (unless i missed it) connect to your account via (s)ftp to upload files, you will need to connect via the ep.io command line tool and either do an rsync or a push of a repo to get files up there.
Update: for more info see my blog post on my experiences with ep.io : http://kencochrane.net/blog/2011/04/my-experiences-with-epio/
Update: Epio closed down on May 31st 2012