I really like Ruby on Rails but I have also developed in node js. Currently I'm making a web app which has chat functionality that could have 30 people in it. For that I want to use node js.
I have never done this, I'm confused on how's traffic divided between app. How is the state shared between apps for example how would I share the user session will I have to hit the database for every request.
My first recommendation is to not split a web app between two separate server platforms. It overly complicates the project and isn't necessary at all.
That being said, if it must be done, you could use one of the platforms as the 'main' one and the other one for API endpoints stationed at localhost:some-port-number. This way, if you were in the main platform (Rails let's say), you could request data via the node.js API by redirecting it to whatever IP address (make it a local IP) that node is running on.
Again, I recommend against this. But that's one solution if it must be done.
Related
I have built two rails apps that need to communicate and send files between each other. For example one rails app would send a request to view a table in the other apps' database. The other app would then render json of that table and send it back. I would also like one app to send a text file stored in its public directory to the other app's public directory.
I have never done anything like this so I don't even know where to begin. Any help would be appreciated. Thanks!
You requirement is common for almost all the web apps irrespective of rails, Communicating with each other is required by most modern web apps. But there is a small understanding that you need to get hold on,
Web sites should not directly access each others internal data (such as tables), (even if they are build by the same language (in this case Rails) by the same developer),
That is where the web-services comes in to play, So you should expose your data through web services so that not only rails application can consume that, but also any app that knows how to consume a web service will get benefit.
Coming back to your question with Rails, rails supports REST web services out of the box, So do some googling about web services, REST web services with rails
HTH
As a starting point, look at ActiveResource.
Railscast
docs
Message queuing systems such as RabbitMQ may be used to communicate things internally between different apps such as a "mailer" app and a main "hub" application.
Alternatively, you can use a shared connection to something like redis stick things onto a "queue" in one app and read them for processing from the other.
In recent Rails versions, it is rather easy to develop API only applications. In the Rails core master, there was even a special application type for these apps briefly (until it got yanked again). But it is still available as a plugin and probably one day becomes actually part of Rails core again. See http://blog.wyeworks.com/2012/4/20/rails-for-api-applications-rails-api-released for more information.
To actually develop and maintain the API of the backend service and make sure both backend and frontend have the same understanding of the resources, you can use ROAR which is great way to build great APIs.
Generally, you should fully define your backend application with an API. Trying to be clever and to skip some of the design steps will only bring you headaches in the long run...
Check out Morpheus. It lets you create RESTful services and use familiar ActiveRecord syntax in the client.
I have a Rails application that right now is pretty standard: Heroku/PostgreSQL backend, users go directly to my site to update data, there's no mobile app or anything. We're going to start licensing out the tech to other companies, so that different versions of the interface live on company1.mywebsite.com, company2.mywebsite.com, etc, where all of these interfaces share the same database.
I want some advice on how to go about building this. Do I create a separate Rails app for company1, company2, etc (with a lot of redundant code) and then set up each of them with API keys to query my master app, using its RESTful routes?
Any tutorials to point me to would be great as well.
I recommend you the book Service Oriented Design with Ruby and Rails, by Paul Dix. It has a lot of info about the kind of system that you want to build.
To answer your question:
Build an API server. It serves a JSON – for example – RESTful interface.
api.mydomain/client1/users.json
Build a frontend server. It consume the API service – using typhoeus for example – and serves the final pages. It uses a subdomain or domain name for identification of different clients.
client1.mydomain/users
We have a similar "platform".
What we did:
build a master API app (REST + Push)
build a core plugin for rails which has all the shared code
build a separate rails app for each client which has all the client specific code
We are using this setup for 3 years now and I'm pretty happy with it.
I'm having an implementation challenge at the moment, it basically consists of two different rails apps.
One rails app (app A) just provides a response in JSON, a record in this case for the nutrition data for one particular food ingredient.
The other app (app B) also Rails provides a front-end for users to view ingredients and match them up with search results provided by app A.
The reason we did this is because we want to eventually make app A into a publicly accessible API for nutrition data, so we figured to take the load off the web App B we could make it stand alone.
I guess I wanted to get the thoughts of you guys on generally how you would handle two systems that need to be tightly integrated in this way.
I would create a new Rails 3 application because Rails 3 is tightly integrated with Rack. Rack allows us to insert various adapters in the request processing chain. Those can help us to differentiate between requests of various kinds (standard requests, API requests).
For the application A I would use something lightweight, like Sinatra (or even my own Rack adapter built from scratch). This is due to the fact that API generally will not use any extra super features of Rails and its magic.
So, strictly speaking, I will create only one application (the application B) on Rails 3 that will have a kind of submodule for the API processing. Thus, they will be binded with each other.
Whether App B is an internal application or external, it's the responsibility of App A to expose the nutrition data. That's something you don't want to duplicate.
The internal App B should use the same mechanism as external applications to access this exposed function. Think of App B as the first client that uses the API.
I'm trying to create a ruby on rails ecommerce application, where potential customers will be able to place an order and the store owner will be able to receive the order in real-time.
The finalized order will be recorded into the database (at the moment SQLite), and the storeowner will have a browser window open, where the new orders will appear just after the order is finalized.
(Application info: I'm using the HOBO rails framework, and planning to host the app in Heroku)
I'm now considering the best technology to implement this, as the application is expected to have a lot of users sending in a lot of orders:
1) Each browser window refreshes the page every X minutes, polling the server continuously for new records (new orders). Of course, this puts a heavy load on the server.
2) As above, but poll the server with some kind of AJAX framework.
3) Use some kind of server push technology, like 'comet' asynchronous messaging. Found Juggernaut, only problem is that it is using Flash and custom ports, and this could be a problem as my app should be accessible behind corporate firewalls and NAT.
4) I'm also checking node.js framework, seems to be efficient for this kind of asynchronous messaging, though it is not supported in Heroku.
Which is the most efficient way to implement this kind of functionality? Is there perhaps another method that I have not thought of?
Thank you for your time and help!
Node.js would probably be a nice fit - it's fast, loves realtime and has great comet support. Only downside is that you are introducing another technology into your solution. It's pretty fun to program in tho and a lot of the libraries have been inspired by rails and sinatra.
I know heroku has been running a node.js beta for a while and people were using it as part of the recent nodeknockout competition. See this blog post. If that's not an option, you could definitely host it elsewhere. If you host it at heroku, you might be able to proxy requests. Otherwise, you could happily run it off a sub domain so you can share cookies.
Also checkout socket.io. It does a great job of choosing the best way to do comet based on the browser's capabilities.
To share data between node and rails, you could share cookies and then store the session data in your database where both applications can get to it. A more involved architecture might involve using Redis to publish messages between them. Or you might be able to get away with passing everything you need in the http requests.
In HTTP, requests can only come from the client. Thus the best options are what you already mentioned (polling and HTTP streaming).
Polling is the easier to implement option; it will use quite a bit of bandwidth though. That's why you should keep the requests and responses as small as possible, so you should definitely use XHR (Ajax) for this.
Your other option is HTTP streaming (Comet); it will require more work on the set up, but you might find it worth the effort. You can give Realtime on Rails a shot. For more information and tips on how to reduce bandwidth usage, see:
http://ajaxpatterns.org/Periodic_Refresh
http://ajaxpatterns.org/HTTP_Streaming
Actually, if you have your storeowner run Chrome (other browsers will follow soon), you can use WebSockets (just for the storeowner's notification though), which allows you to have a constant connection open, and you can send data to the browser without the browser requesting anything.
There are a few websocket libraries for node.js, but i believe you can do it easily yourself using just a regular tcp connection.
I use a web service to convert files. The service returns the converted file as an HTTP POST, along with identifier data. My app receives the response, updates its database and saves the file to the appropriate location.
At least that's the idea, but how do I develop and test this on a local machine? Since it isn't publicly facing, I can't provide a directive URL. What's the best way to handle this? I want to keep the process as clean as possible, and the only ideas I can come up with have seemed excessively kludgey.
Given how common REST API development is, I assume there are well-established best practices for this. Any help appreciated.
The solution will change a bit depending on which server your using.
But the generally accepted method is using the loopback address: 127.0.0.1 in place of a fully qualified domain name. Your server may need to be reconfigured to listen on this IP address, but that's usually a trivial fix.
example: http://127.0.0.1/path/to/resource.html
You can use curl or even your browser if your application has a proper frontend. There are many other similar tools to test this from a command line, and each language has a set of libraries for establishing http connections and transferring data along them.
If your machine isn't accessible to the service you are using, then your only option would really be to build a local implementation of the service that will exercise your API. A rake task that sends the POST with the file and the info would be a nice thing so you could start your rails app locally, and then kick off the task with some params to run your application through its paces.
This is the case any time you are trying to develop a system that can't connect to a required resource during development. You need to build a development harness of sorts so that you can exercise all the different types of actions the external service will call on your application.
This certainly won't be easy or straight forward, especially if your interface to this external service is complicated. Be sure to have your test cases send bad POSTs to your application so that you are sure you handle both what you expect, and what you don't.
Also make sure that you do some integration testing with the actual service before you "go-live" with the application. Hopefully you can deploy to an external server that the web service will be able to access in order to test. Amazon's EC2 hosting environment would let you set up a server very quickly, run your tests, and then shut down without much cost at all.
You have 2 options:
Set up dynamic dns and expose your app to the outside world. This only works if you have full control over your network.
Use something like webrat to fake the posts to your app. Since it's only 1 request, this seems pretty trivial.
Considering that you should be writing automated tests for this, I'd go with #2. I used to do #1 when developing facebook apps since there was far to many requests to mock them all out with webrat.
If your question is about testing, why don't you use mocks to fake the server? It's more elegant than using Webrat, and easier to deploy (you only have one app instead of an app and a test environment).
More info about mocks http://blog.floehopper.org/presentations/lrug-mock-objects-2007-07-09/
You've got some info about mocks with Rspec here http://rspec.info/documentation/mocks/