diff options
Diffstat (limited to 'actioncable/README.md')
| -rw-r--r-- | actioncable/README.md | 32 |
1 files changed, 16 insertions, 16 deletions
diff --git a/actioncable/README.md b/actioncable/README.md index c85d59a1c8..334c75c79c 100644 --- a/actioncable/README.md +++ b/actioncable/README.md @@ -39,7 +39,7 @@ reflections of each unit. ### A full-stack example The first thing you must do is define your `ApplicationCable::Connection` class in Ruby. This -is the place where you authorize the incoming connection, and proceed to establish it +is the place where you authorize the incoming connection, and proceed to establish it, if all is well. Here's the simplest example starting with the server-side connection class: ```ruby @@ -73,7 +73,7 @@ use that to set the `current_user`. By identifying the connection by this same c 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 +Next, you should define your `ApplicationCable::Channel` class in Ruby. This is the place where you put shared logic between your channels. ```ruby @@ -94,7 +94,7 @@ The client-side needs to setup a consumer instance of this connection. That's do 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 +The `ws://cable.example.com` address must point to your Action Cable server(s), and it must share a cookie namespace with the rest of the application (which may live under http://example.com). This ensures that the signed cookie will be correctly sent. @@ -105,8 +105,8 @@ is defined by declaring channels on the server and allowing the consumer to subs ### Channel example 1: User appearances -Here's a simple example of a channel that tracks whether a user is online or not and what page they're on. -(This is useful for creating presence features like showing a green dot next to a user name if they're online). +Here's a simple example of a channel that tracks whether a user is online or not, and also what page they are currently on. +(This is useful for creating presence features like showing a green dot next to a user's name if they're online). First you declare the server-side channel: @@ -180,7 +180,7 @@ App.cable.subscriptions.create "AppearanceChannel", Simply calling `App.cable.subscriptions.create` will setup the subscription, which will call `AppearanceChannel#subscribed`, which in turn is linked to original `App.cable` -> `ApplicationCable::Connection` instances. -We then link the client-side `appear` method to `AppearanceChannel#appear(data)`. This is possible because the server-side +Next, we link the client-side `appear` method to `AppearanceChannel#appear(data)`. This is possible because the server-side channel instance will automatically expose the public methods declared on the class (minus the callbacks), so that these can be reached as remote procedure calls via a subscription's `perform` method. @@ -215,7 +215,7 @@ ActionCable.server.broadcast \ "web_notifications_#{current_user.id}", { title: 'New things!', body: 'All the news that is fit to print' } ``` -The `ActionCable.server.broadcast` call places a message in the Redis' pubsub queue under a separate broadcasting name for each user. For a user with an ID of 1, the broadcasting name would be `web_notifications_1`. +The `ActionCable.server.broadcast` call places a message in the Action Cable pubsub queue under a separate broadcasting name for each user. For a user with an ID of 1, the broadcasting name would be `web_notifications_1`. The channel has been instructed to stream everything that arrives at `web_notifications_1` directly to the client by invoking the `#received(data)` callback. The data is the hash sent as the second parameter to the server-side broadcast call, JSON encoded for the trip across the wire, and unpacked for the data argument arriving to `#received`. @@ -234,7 +234,7 @@ class ChatChannel < ApplicationCable::Channel end ``` -Pass an object as the first argument to `subscriptions.create`, and that object will become your params hash in your cable channel. The keyword `channel` is required. +If you pass an object as the first argument to `subscriptions.create`, that object will become the params hash in your cable channel. The keyword `channel` is required. ```coffeescript # Client-side, which assumes you've already requested the right to send web notifications @@ -293,7 +293,7 @@ The rebroadcast will be received by all connected clients, _including_ the clien ### More complete examples -See the [rails/actioncable-examples](http://github.com/rails/actioncable-examples) repository for a full example of how to setup Action Cable in a Rails app and adding channels. +See the [rails/actioncable-examples](http://github.com/rails/actioncable-examples) repository for a full example of how to setup Action Cable in a Rails app, and how to add channels. ## Configuration @@ -349,11 +349,11 @@ something like: `App.cable = ActionCable.createConsumer("/cable")`. 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". -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 +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 Action Cable 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: +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" @@ -412,7 +412,7 @@ 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 `/cable`, mount the server at that path: +If you are using a threaded server like Puma or Thin, the current implementation of Action Cable 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 @@ -421,7 +421,7 @@ Example::Application.routes.draw do end ``` -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. +For every instance of your server you create and for every worker your server spawns, you will also have a new instance of Action Cable, but the use of Redis keeps messages synced across connections. ### Notes @@ -433,14 +433,14 @@ The WebSocket server doesn't have access to the session, but it has access to th ## Dependencies -Action Cable provides a subscription adapter interface to process its pubsub internals. By default, asynchronous, inline, PostgreSQL, evented Redis, and non-evented Redis adapters are included. The default adapter in new Rails applications is the asynchronous (`async`) adapter. To create your own adapter, you can look at `ActionCable::SubscriptionAdapter::Base` for all methods that must be implemented, and any of the adapters included within ActionCable as example implementations. +Action Cable provides a subscription adapter interface to process its pubsub internals. By default, asynchronous, inline, PostgreSQL, evented Redis, and non-evented Redis adapters are included. The default adapter in new Rails applications is the asynchronous (`async`) adapter. To create your own adapter, you can look at `ActionCable::SubscriptionAdapter::Base` for all methods that must be implemented, and any of the adapters included within Action Cable as example implementations. The Ruby side of things is built on top of [websocket-driver](https://github.com/faye/websocket-driver-ruby), [nio4r](https://github.com/celluloid/nio4r), and [concurrent-ruby](https://github.com/ruby-concurrency/concurrent-ruby). ## Deployment -Action Cable is powered by a combination of websockets and threads. All of the +Action Cable is powered by a combination of WebSockets and threads. All of the connection management is handled internally by utilizing Ruby’s native thread support, which means you can use all your regular Rails models with no problems as long as you haven’t committed any thread-safety sins. |