diff options
| -rw-r--r-- | actionpack/lib/action_controller/metal/live.rb | 74 | ||||
| -rw-r--r-- | actionpack/test/controller/live_stream_test.rb | 88 |
2 files changed, 162 insertions, 0 deletions
diff --git a/actionpack/lib/action_controller/metal/live.rb b/actionpack/lib/action_controller/metal/live.rb index 8092fd639f..0dd788645b 100644 --- a/actionpack/lib/action_controller/metal/live.rb +++ b/actionpack/lib/action_controller/metal/live.rb @@ -1,5 +1,6 @@ require 'action_dispatch/http/response' require 'delegate' +require 'active_support/json' module ActionController # Mix this module in to your controller, and all actions in that controller @@ -32,6 +33,79 @@ module ActionController # the main thread. Make sure your actions are thread safe, and this shouldn't # be a problem (don't share state across threads, etc). module Live + # This class provides the ability to write an SSE (Server Sent Event) + # to an IO stream. The class is initialized with a stream and can be used + # to either write a JSON string or an object which can be converted to JSON. + # + # Writing an object will convert it into standard SSE format with whatever + # options you have configured. You may choose to set the following options: + # + # 1) Event. If specified, an event with this name will be dispatched on + # the browser. + # 2) Retry. The reconnection time in milliseconds used when attempting + # to send the event. + # 3) Id. If the connection dies while sending an SSE to the browser, then + # the server will receive a +Last-Event-ID+ header with value equal to +id+. + # + # After setting an option in the constructor of the SSE object, all future + # SSEs sent accross the stream will use those options unless overridden. + # + # Example Usage: + # + # class MyController < ActionController::Base + # include ActionController::Live + # + # def index + # response.headers['Content-Type'] = 'text/event-stream' + # sse = SSE.new(response.stream, retry: 300, event: "event-name") + # sse.write({ name: 'John'}) + # sse.write({ name: 'John'}, id: 10) + # sse.write({ name: 'John'}, id: 10, event: "other-event") + # sse.write({ name: 'John'}, id: 10, event: "other-event", retry: 500) + # ensure + # sse.close + # end + # end + # + # Note: SSEs are not currently supported by IE. However, they are supported + # by Chrome, Firefox, Opera, and Safari. + class SSE + + WHITELISTED_OPTIONS = %w( retry event id ) + + def initialize(stream, options = {}) + @stream = stream + @options = options + end + + def close + @stream.close + end + + def write(object, options = {}) + case object + when String + perform_write(object, options) + else + perform_write(ActiveSupport::JSON.encode(object), options) + end + end + + private + + def perform_write(json, options) + current_options = @options.merge(options).stringify_keys + + WHITELISTED_OPTIONS.each do |option_name| + if (option_value = current_options[option_name]) + @stream.write "#{option_name}: #{option_value}\n" + end + end + + @stream.write "data: #{json}\n\n" + end + end + class Buffer < ActionDispatch::Response::Buffer #:nodoc: def initialize(response) @error_callback = nil diff --git a/actionpack/test/controller/live_stream_test.rb b/actionpack/test/controller/live_stream_test.rb index e727b27db0..0a431270b5 100644 --- a/actionpack/test/controller/live_stream_test.rb +++ b/actionpack/test/controller/live_stream_test.rb @@ -2,6 +2,94 @@ require 'abstract_unit' require 'active_support/concurrency/latch' module ActionController + class SSETest < ActionController::TestCase + class SSETestController < ActionController::Base + include ActionController::Live + + def basic_sse + response.headers['Content-Type'] = 'text/event-stream' + sse = SSE.new(response.stream) + sse.write("{\"name\":\"John\"}") + sse.write({ name: "Ryan" }) + ensure + sse.close + end + + def sse_with_event + sse = SSE.new(response.stream, event: "send-name") + sse.write("{\"name\":\"John\"}") + sse.write({ name: "Ryan" }) + ensure + sse.close + end + + def sse_with_retry + sse = SSE.new(response.stream, retry: 1000) + sse.write("{\"name\":\"John\"}") + sse.write({ name: "Ryan" }, retry: 1500) + ensure + sse.close + end + + def sse_with_id + sse = SSE.new(response.stream) + sse.write("{\"name\":\"John\"}", id: 1) + sse.write({ name: "Ryan" }, id: 2) + ensure + sse.close + end + end + + tests SSETestController + + def wait_for_response_stream_close + while !response.stream.closed? + sleep 0.01 + end + end + + def test_basic_sse + get :basic_sse + + wait_for_response_stream_close + assert_match(/data: {\"name\":\"John\"}/, response.body) + assert_match(/data: {\"name\":\"Ryan\"}/, response.body) + end + + def test_sse_with_event_name + get :sse_with_event + + wait_for_response_stream_close + assert_match(/data: {\"name\":\"John\"}/, response.body) + assert_match(/data: {\"name\":\"Ryan\"}/, response.body) + assert_match(/event: send-name/, response.body) + end + + def test_sse_with_retry + get :sse_with_retry + + wait_for_response_stream_close + first_response, second_response = response.body.split("\n\n") + assert_match(/data: {\"name\":\"John\"}/, first_response) + assert_match(/retry: 1000/, first_response) + + assert_match(/data: {\"name\":\"Ryan\"}/, second_response) + assert_match(/retry: 1500/, second_response) + end + + def test_sse_with_id + get :sse_with_id + + wait_for_response_stream_close + first_response, second_response = response.body.split("\n\n") + assert_match(/data: {\"name\":\"John\"}/, first_response) + assert_match(/id: 1/, first_response) + + assert_match(/data: {\"name\":\"Ryan\"}/, second_response) + assert_match(/id: 2/, second_response) + end + end + class LiveStreamTest < ActionController::TestCase class TestController < ActionController::Base include ActionController::Live |