diff options
Diffstat (limited to 'actioncable/README.md')
| -rw-r--r-- | actioncable/README.md | 93 |
1 files changed, 56 insertions, 37 deletions
diff --git a/actioncable/README.md b/actioncable/README.md index 823964343a..63e328321b 100644 --- a/actioncable/README.md +++ b/actioncable/README.md @@ -1,4 +1,4 @@ -# Action Cable –- Integrated WebSockets for Rails +# Action Cable – Integrated WebSockets for Rails Action Cable seamlessly integrates WebSockets with the rest of your Rails application. It allows for real-time features to be written in Ruby in the same style @@ -16,7 +16,7 @@ WebSockets open to your application if they use multiple browser tabs or devices The client of a WebSocket connection is called the consumer. Each consumer can in turn subscribe to multiple cable channels. Each channel encapsulates -a logical unit of work, similar to what a controller does in a regular MVC setup. For example, +a logical unit of work, similar to what a controller does in a regular MVC setup. For example, you could have a `ChatChannel` and a `AppearancesChannel`, and a consumer could be subscribed to either or to both of these channels. At the very least, a consumer should be subscribed to one channel. @@ -66,6 +66,13 @@ end Here `identified_by` is a connection identifier that can be used to find the specific connection again or later. Note that anything marked as an identifier will automatically create a delegate by the same name on any channel instances created off the connection. +This relies on the fact that you will already have handled authentication of the user, and +that a successful authentication sets a signed cookie with the `user_id`. This cookie is then +automatically sent to the connection instance when a new connection is attempted, and you +use that to set the `current_user`. By identifying the connection by this same current_user, +you're also ensuring that you can later retrieve all open connections by a given user (and +potentially disconnect them all if the user is deleted or deauthorized). + Then you should define your `ApplicationCable::Channel` class in Ruby. This is the place where you put shared logic between your channels. @@ -77,13 +84,6 @@ module ApplicationCable end ``` -This relies on the fact that you will already have handled authentication of the user, and -that a successful authentication sets a signed cookie with the `user_id`. This cookie is then -automatically sent to the connection instance when a new connection is attempted, and you -use that to set the `current_user`. By identifying the connection by this same current_user, -you're also ensuring that you can later retrieve all open connections by a given user (and -potentially disconnect them all if the user is deleted or deauthorized). - The client-side needs to setup a consumer instance of this connection. That's done like so: ```coffeescript @@ -91,7 +91,7 @@ The client-side needs to setup a consumer instance of this connection. That's do #= require action_cable @App = {} -App.cable = Cable.createConsumer("ws://cable.example.com") +App.cable = ActionCable.createConsumer("ws://cable.example.com") ``` The ws://cable.example.com address must point to your set of Action Cable servers, and it @@ -298,11 +298,12 @@ See the [rails/actioncable-examples](http://github.com/rails/actioncable-example ## Configuration -Action Cable has two required configurations: the Redis connection and specifying allowed request origins. +Action Cable has three required configurations: the Redis connection, allowed request origins, and the cable server url (which can optionally be set on the client side). ### Redis -By default, `ActionCable::Server::Base` will look for a configuration file in `Rails.root.join('config/redis/cable.yml')`. The file must follow the following format: +By default, `ActionCable::Server::Base` will look for a configuration file in `Rails.root.join('config/cable.yml')`. +This file must specify a Redis url for each Rails environment. It may use the following format: ```yaml production: &production @@ -312,11 +313,10 @@ development: &development test: *development ``` -This format allows you to specify one configuration per Rails environment. You can also change the location of the Redis config file in -a Rails initializer with something like: +You can also change the location of the Redis config file in a Rails initializer with something like: ```ruby -Rails.application.paths.add "config/redis/cable", with: "somewhere/else/cable.yml" +Rails.application.paths.add "config/cable", with: "somewhere/else/cable.yml" ``` ### Allowed Request Origins @@ -327,29 +327,31 @@ Action Cable will only accept requests from specified origins, which are passed ActionCable.server.config.allowed_request_origins = ['http://rubyonrails.com', /http:\/\/ruby.*/] ``` +When running in the development environment, this defaults to "http://localhost:3000". + To disable and allow requests from any origin: ```ruby ActionCable.server.config.disable_request_forgery_protection = true ``` -By default, Action Cable allows all requests from localhost:3000 when running in the development environment. +### Consumer Configuration -### Other Configurations +Once you have decided how to run your cable server (see below), you must provide the server url (or path) to your client-side setup. +There are two ways you can do this. -The other common option to configure is the log tags applied to the per-connection logger. Here's close to what we're using in Basecamp: +The first is to simply pass it in when creating your consumer. For a standalone server, +this would be something like: `App.cable = ActionCable.createConsumer("ws://example.com:28080")`, and for an in-app server, +something like: `App.cable = ActionCable.createConsumer("/cable")`. -```ruby -ActionCable.server.config.log_tags = [ - -> request { request.env['bc.account_id'] || "no-account" }, - :action_cable, - -> request { request.uuid } -] -``` +The second option is to pass the server url through the `action_cable_meta_tag` in your layout. +This uses a url or path typically set via `config.action_cable.url` in the environment configuration files, or defaults to "/cable". -Your websocket url might change between environments. If you host your production server via https, you will need to use the wss scheme +This method is especially useful if your websocket url might change between environments. If you host your production server via https, you will need to use the wss scheme for your ActionCable server, but development might remain http and use the ws scheme. You might use localhost in development and your -domain in production. In any case, to vary the websocket url between environments, add the following configuration to each environment: +domain in production. + +In any case, to vary the websocket url between environments, add the following configuration to each environment: ```ruby config.action_cable.url = "ws://example.com:28080" @@ -364,7 +366,19 @@ Then add the following line to your layout before your JavaScript tag: And finally, create your consumer like so: ```coffeescript -App.cable = Cable.createConsumer() +App.cable = ActionCable.createConsumer() +``` + +### Other Configurations + +The other common option to configure is the log tags applied to the per-connection logger. Here's close to what we're using in Basecamp: + +```ruby +ActionCable.server.config.log_tags = [ + -> request { request.env['bc.account_id'] || "no-account" }, + :action_cable, + -> request { request.uuid } +] ``` For a full list of all configuration options, see the `ActionCable::Server::Configuration` class. @@ -394,22 +408,19 @@ Then you start the server using a binstub in bin/cable ala: bundle exec puma -p 28080 cable/config.ru ``` -The above will start a cable server on port 28080. Remember to point your client-side setup against that using something like: -`App.cable = Cable.createConsumer("ws://basecamp.dev:28080")`. +The above will start a cable server on port 28080. ### In app -If you are using a threaded server like Puma or Thin, the current implementation of ActionCable can run side-along with your Rails application. For example, to listen for WebSocket requests on `/websocket`, match requests on that path: +If you are using a threaded server like Puma or Thin, the current implementation of ActionCable can run side-along with your Rails application. For example, to listen for WebSocket requests on `/cable`, mount the server at that path: ```ruby # config/routes.rb Example::Application.routes.draw do - match "/websocket", :to => ActionCable.server, via: [:get, :post] + mount ActionCable.server => '/cable' end ``` -You can use `App.cable = Cable.createConsumer("/websocket")` to connect to the cable server. - For every instance of your server you create and for every worker your server spawns, you will also have a new instance of ActionCable, but the use of Redis keeps messages synced across connections. ### Notes @@ -427,7 +438,7 @@ messages back and forth over the WebSocket cable connection. This dependency may be alleviated in the future, but for the moment that's what it is. So be sure to have Redis installed and running. -The Ruby side of things is built on top of [faye-websocket](https://github.com/faye/faye-websocket-ruby) and [celluloid](https://github.com/celluloid/celluloid). +The Ruby side of things is built on top of [faye-websocket](https://github.com/faye/faye-websocket-ruby) and [concurrent-ruby](https://github.com/ruby-concurrency/concurrent-ruby). ## Deployment @@ -452,6 +463,14 @@ Action Cable is released under the MIT license: ## Support -Bug reports can be filed for the alpha development project here: +API documentation is at: + +* http://api.rubyonrails.org + +Bug reports can be filed for the Ruby on Rails project here: + +* https://github.com/rails/rails/issues + +Feature requests should be discussed on the rails-core mailing list here: -* https://github.com/rails/actioncable/issues +* https://groups.google.com/forum/?fromgroups#!forum/rubyonrails-core |