I want to use server-side events with rails. It works locally without any problem. But it does not trigger on production with unicorn.
Is it possible to use SSE with unicorn?
You need a threaded web server such as Puma, as each connection requires a separate thread to keep the long running connection open.
Related
I was wondering if there was a way to use the Puma server (Rails default) JUST on the new Rails 5.1 system tests?
Right now on all our projects we use tiny_tds, but I was trying to experiment with 5.1 system tests with Capybara/Selenium but it fails of course because I do not have Puma installed/running.
I took a look through the documentation and didn't see anything about declaring what type of server you want to use. Were connecting to a SQL Server database so I don't know if Puma is able to do that (And that's probably why were using tiny_tds in the first place).
You're confusing database adapters and rack web servers which are very different things.
Puma (like Webrick, Thin, Unicorn etc) is a general purpose Rack web server. It sits and waits for incoming requests from vistors and dispatches them to an application (like a Rails app) by calling it with a hash containing the environment and request. The application returns an array containing the response. The server sends it back to the visitor.
tiny_tds on the other hand is a database adapter. Its used to connect the application to the database. The web server is almost completly oblivious to how the application creates a response from the request. This includes whatever databases are used.
In Rails 5 most servers don't require configuration. You just add the gem to the gemfile and run bundle install and they plug themselves in. There in no seperate installation step.
That was not the case earlier which is why Webrick - a server with the only real merit being that it does not require configuration was the default. It is now Puma which unlike Webrick is suited for production.
Using different servers in different environments is not a good idea since it violates the idea of dev/prod parity. Your dev & test environment should be as close as possible to what you are deploying to so that you can catch bugs before they end up in production. This means you should be running the same server, same database etc.
Running a seperate test server for different parts of your test suite sounds like a true fools errand - if its even possible without hacking the framework to bits.
For SQL Server there is activerecord-sqlserver-adapter which can use tiny_tds as a backend.
I'm running my Rails application through thin on Windows OS.
thin start -e production
Since the number of users grew, now around 10 people using the app simultaneously, there are times when a same page takes a while longer to load.
Are there other configurations that I need to set when running the server on production?
I'm quite sure that it has to do with the server since the slow down happens on pages that normally loads fast.
The Thin webserver is not meant to production environment. Instead of this you should use a different webserver and application server like Nginx/Unicorn, Nginx/Passenger.
I would recommend Passenger to run your rails app as fast as possible in production mode.
The thin webserver is very fast for few requests, but if there are simultaneously requests, thin gets very slow.
The following document describes about how to deploy rails application in windows. I haven't done this personally but, believe the latest versions should allow that. Please check the below link to see how it can be done
http://weblog.rubyonrails.org/2006/5/11/deploying-rails-on-windows-servers/
My webapp consits of a HTTP server and a WebSocket server, both running on Rails. For Websockets I am using em-websocket which I start in the initializers, like this:
Thread.new do
EventMachine.run do
EventMachine::WebSocket.run(EVENTCHAT_CONFIG) do |socket|
[...]
end
end
end if Rails.const_defined?(:Server)
This works fine when I start the server with 'rails s', but it doesn't work in detached mode ('rails s -d'). When I try to connect to the Websocket server via JS it tells me, that it is still in connecting state, so I guess something is blocking it.
I also think this might be related to the threading.
I also tried starting the server with thin and unicorn, but both fail to start the Websocket Server.
Am I going against the convention here?
I just made the switch to foreman, which enables me to start multiple ruby processes with one command. You just have to add a Procfile. For deployments you can export this to various init systems, like in my case upstart.
It doesn't work for me yet, though I do think this is the way to go.
Is it possible to hot deploy Ruby just like PHP?
Normally I used FTP to upload the PHP file, then it will be available automatically.
Can Ruby hot deploy its file like this?
Your comment welcome.
Are you talking about a ruby on rails application ?
If so, when deploying a rails application in production mode, the all application gets loaded in memory. So changing the files won't affect the running application.
For hot restarting a rails application you will need to use solution such as:
Unicorn
Puma
Passenger
For a first time, Puma is the easiest way.
However if you are looking for a zero-downtime, either Unicorn or Passenger enterprise are what you are looking for.
EDIT
Unicorn
Free
Complex configuration
zero-downtime when hot restarting. when hot-restarting unicorn, it keeps the old threads working until the new ones are fully functionnal. So if the new ones fail to start, nothing happens. The old ones just keep going.
Puma
Free
Simple configuration
hot restart but no zero-downtime. When hot-restarting puma, it shuts down the old threads and starts the new ones. Puma keeps the sockets open, so the client are not disconnected, but are waiting to get a response while the new threads restart. However if the new threads fail to start, Puma can't restart the old ones. So connections are lost and the server is down.
Passenger
Free edition
Free
The configuration is easier than unicorn
hot-restart, but no zero-downtime. Like Puma.
Enterprise edition
$29/mo
The configuration is easier than unicorn
zero-downtime when hot restarting. Like Unicorn.
I need a recommendation for a rails web server to use for development on windows. I was happy with the default rails server until I had to handle two concurrent requests which it does not support (a page calls an internal rest service). I want to keep the "rails s" experience, so which is the simplest server that support my needs?
To my knowledge, there is no Windows-compatible Rails web server that is multi-threaded or concurrent out of the box.
You will need to spawn multiple back-end servers (we use mongrel, you could use thin instead) and then use/configure a proxy server (we use nginx) in front of them to handle multiple requests concurrently on Windows.
This blog post describes setting up Thin and nginx on Windows, once running you can edit the nginx.conf to proxy to multiple thin instances/ports.