Real-time Web Technologies
Last Modified: 2016-09-19
Notes about real-time web technologies and two-way communication on the web
WebSockets Long Polling Server-Sent Events EventSource Event Streaming WebHooks WebRTC
TODO WebHooks, WebRTC TODO https://www.leggetter.co.uk/2015/12/18/real-time-data-fundamentals.html TODO https://github.com/leggetter/realtime-web-technologies-guide/blob/master/guide.md TODO https://en.wikipedia.org/wiki/Comet_(programming) TODO https://en.wikipedia.org/wiki/PubSubHubbub TODO backplane options for multi-instance scenarios
Resources
- An overview of realtime libraries and frameworks
- Real-time web technologies guide
- Push: SSE vs WebSockets
- Benchmark: Server-Sent Events vs polling
TODO http://dsheiko.com/weblog/websockets-vs-sse-vs-long-polling/ TODO http://stackoverflow.com/questions/18799364/webrtc-vs-websockets-if-webrtc-can-do-video-audio-and-data-why-do-i-need-web TODO https://docs.google.com/document/d/1idl_NYQhllFEFqkGQOLv8KBK8M3EVzyvxnKkHl4SuM8/edit TODO https://www.youtube.com/watch?v=p2HzZkd2A40
TODO why not SSE https://news.ycombinator.com/item?id=9419920 TODO https://github.com/jpignata/blog/blob/master/articles/server-sent-events.md
TODO push frameworks https://azure.microsoft.com/en-us/documentation/articles/notification-hubs-aspnet-backend-windows-dotnet-wns-notification/
Technologies
- WebSockets
- Long Polling (COMET)
- Server-Sent Events (EventSource)
- WebRTC
- Forever Frame (COMET)
- TODO Pub/Sub
- TODO Protocols
- TODO Caches
- TODO https://nchan.slact.net/
- TODO Webhooks & Firehose
- TODO WAMP https://en.wikipedia.org/wiki/Web_Application_Messaging_Protocol
- http://wamp-proto.org/ http://wamp-proto.org/why/ https://github.com/wamp-proto
Frameworks
- SignalR
- Event Streaming FWs
Server-Sent Events (EventSource)
- Server has endpoint that streams messages to subscribers (one-way)
- Persistent http connection optimized for this purpose
- Polls every 3 seconds? Configurable?
- Text-based format with optional type information
- Client uses the EventSource interface (javascript) to subscribe to the stream or only to messages of certain type
-
Response content type must be “text/event-stream”?
-
Not ubiquitous but can be used on older browsers using a polyfill (e.g. this one
- What is Server-Sent Events
- MDN: Using server-sent events
- https://developer.mozilla.org/en-US/docs/Web/API/Server-sent_events (polyfills listed here also)
- W3C: Server-Sent Events
- w3schools
- html5rocks
- HTML Living Standard
- Using HTML5 Server-Sent Events with JSON and ASP.NET MVC
- Streaming data with ASP.NET WEB API and pushcontentstream
- HTML5 and Server-Sent Events
- Native HTML5 push notifications with ASP.NET Web API and Knockout.js
- Server-Sent Event Notifications with HTML5
- HTML5 Server-Sent Events
- Server-sent events List of libraries here
- When server-sent events (SSE) is much better choice than websocket
- https://www.sitepoint.com/real-time-apps-websockets-server-sent-events/
- http://html5doctor.com/server-sent-events/
- http://techbrij.com/real-time-chart-html5-push-sse-asp-net-web-api
- https://blogs.msdn.microsoft.com/henrikn/2012/04/23/recent-asp-net-web-api-updates-april-24/ (Scroll down to Push Content)
- http://stackoverflow.com/questions/12992242/webapi-and-html5-sse
- https://www.justinribeiro.com/chronicle/2014/04/09/sse-asp-net-mvc-double-message/
- http://www.c-sharpcorner.com/UploadFile/manish1231/learn-html5-part-3-server-sent-events-apis/
Security
- http://stackoverflow.com/questions/20324657/eventsource-sse-server-sent-svents-security
- http://stackoverflow.com/questions/28176933/http-authorization-header-in-eventsource-server-sent-events
- http://stackoverflow.com/questions/27898622/server-sent-events-stopped-work-after-enabling-ssl-on-proxy
Client polyfills
- https://github.com/Yaffle/EventSource/
- https://github.com/remy/polyfills/blob/master/EventSource.js
- https://github.com/rwaldron/jquery.eventsource
- https://github.com/amvtek/EventSource
SignalR
- https://blogs.msdn.microsoft.com/webdev/2013/11/14/azure-web-site-now-supports-websockets/
- http://www.asp.net/signalr/overview/getting-started/introduction-to-signalr
- http://www.asp.net/signalr/overview/getting-started/tutorial-getting-started-with-signalr
- http://www.asp.net/signalr/overview/getting-started/tutorial-high-frequency-realtime-with-signalr
- http://www.asp.net/signalr/overview/getting-started/real-time-web-applications-with-signalr
- http://www.asp.net/signalr/overview/guide-to-the-api/handling-connection-lifetime-events
- http://www.asp.net/signalr/overview/deployment
- http://www.asp.net/signalr/overview/deployment/tutorial-signalr-self-host
- http://www.asp.net/signalr/overview/deployment/using-signalr-with-azure-web-sites
- http://www.asp.net/signalr/overview/guide-to-the-api
- http://www.asp.net/signalr/overview/guide-to-the-api/hubs-api-guide-server
- http://www.asp.net/signalr/overview/guide-to-the-api/hubs-api-guide-server#multiplehubs
- http://www.asp.net/signalr/overview/guide-to-the-api/hubs-api-guide-net-client
- http://www.asp.net/signalr/overview/guide-to-the-api/hubs-api-guide-javascript-client
- http://www.asp.net/signalr/overview/guide-to-the-api/working-with-groups
- http://www.asp.net/signalr/overview/performance
- Interesting question: http://stackoverflow.com/questions/22771162/can-multiple-instances-of-signalr-be-configured-to-use-a-different-message-bus-f
- http://sravi-kiran.blogspot.fi/2013/09/ABetterWayOfUsingAspNetSignalRWithAngularJs.html
- https://dzone.com/articles/better-way-using-aspnet Mirror
- https://www.sitepoint.com/build-real-time-signalr-dashboard-angularjs/
- https://azure.microsoft.com/en-us/blog/introduction-to-websockets-on-windows-azure-web-sites/
- http://www.asp.net/signalr/overview/security/introduction-to-security
- http://www.asp.net/signalr/overview/security/hub-authorization
- http://henriquat.re/server-integration/signalr/integrateWithSignalRHubs.html
- https://www.sitepoint.com/real-time-apps-websockets-server-sent-events/
- http://www.asp.net/signalr/overview/guide-to-the-api/hubs-api-guide-javascript-client
- http://henriquat.re/server-integration/signalr/integrateWithSignalRHubs.html
- http://developer.telerik.com/featured/whats-the-buzz-a-real-time-chat-room-with-telerik-ui-and-signalr/
- https://blog.3d-logic.com/2015/03/29/signalr-on-the-wire-an-informal-description-of-the-signalr-protocol/
- http://techbrij.com/jquery-flot-signalr-asp-net-mvc-chart
Persistent Connections (using without hubs)
- https://github.com/SignalR/SignalR/wiki/QuickStart-Persistent-Connections
- https://github.com/SignalR/SignalR/wiki/PersistentConnection
- http://stackoverflow.com/questions/21512587/signalr-2-0-2-creating-persistentconnection
- https://pepitosolis.wordpress.com/2013/11/27/signalr-2-0-persistentconnection-example/
Selective updates
- https://www.simple-talk.com/dotnet/asp-net/selective-updates-with-asp-net-signalr/
- http://www.asp.net/signalr/overview/guide-to-the-api/mapping-users-to-connections
- http://stackoverflow.com/questions/37377396/signalr-send-message-to-specific-client
- http://stackoverflow.com/questions/19522103/signalr-sending-a-message-to-a-specific-user-using-iuseridprovider-new-2-0
Scaling
- http://www.asp.net/signalr/overview/performance/scaleout-in-signalr
- http://www.asp.net/signalr/overview/performance/scaleout-with-windows-azure-service-bus
- http://www.asp.net/signalr/overview/performance/scaleout-with-redis
- http://www.asp.net/signalr/overview/performance/scaleout-with-sql-server
- https://github.com/mdevilliers/SignalR.RabbitMq
- https://roycornelissen.wordpress.com/2013/03/11/an-nservicebus-backplane-for-signalr/
- https://github.com/roycornelissen/signalr.nservicebus
- http://blog.jaywayco.co.uk/signalr-superhero-scale-out-in-azure/
- http://scottcodes.net/signalr-load-balancing
Security
- http://www.asp.net/signalr/overview/security
- http://www.asp.net/signalr/overview/security/introduction-to-security
- http://www.asp.net/signalr/overview/security/hub-authorization
- http://www.asp.net/signalr/overview/security/persistent-connection-authorization
Custom (e.g. claims) authorization http://www.asp.net/signalr/overview/security/hub-authorization#custom
http://www.asp.net/signalr/overview/security/introduction-to-security#groupsecurity:
Do not use groups as a security mechanism
Groups are a convenient way of collecting related users, but they are not a secure mechanism for limiting access to sensitive information. This is especially true when users can automatically rejoin groups during a reconnect. Instead, consider adding privileged users to a role and limiting access to a hub method to only members of that role. For an example of restricting access based on a role, see Authentication and Authorization for SignalR Hubs. For an example of checking user access to groups when reconnecting, see Working with groups.
Multitenancy
- https://apprenda.com/blog/a-multi-tenant-real-time-app-with-apprenda-and-signalr/
- https://social.msdn.microsoft.com/Forums/en-US/4b07a59d-fc86-4b7a-86ab-af07fa2ee684/signalr-notifications-to-an-specific-user-for-multi-tenant-application?forum=lightswitch
- http://www.asp.net/signalr/overview/guide-to-the-api/working-with-groups
Client side libraries
- [AngularJS] https://github.com/JustMaier/angular-signalr-hub
Redis Publish/subscribe
- http://redis.io/topics/pubsub
- http://webd.is/
- https://www.toptal.com/go/going-real-time-with-redis-pubsub
- http://stackoverflow.com/questions/6437741/how-to-use-servicestack-redis-in-a-web-application-to-take-advantage-of-pub-su
Forum posts
- http://stackoverflow.com/questions/9537641/node-js-socket-io-vs-signalr-vs-c-sharp-websocket-server
WebSocket Frameworks/server side libraries
deepstream.io
- https://deepstream.io/
- https://deepstreamhub.com/
socket.io
SignalR
- http://www.asp.net/signalr/overview/getting-started/introduction-to-signalr
- https://www.simple-talk.com/dotnet/asp-net/asp-net-signalr-old-fashioned-polling-just-done-better/
- https://www.npmjs.com/package/angular-signalr-hub
- http://kevgriffin.com/why-should-asp-net-developers-consider-signalr-for-all-projects/
- http://www.hanselman.com/blog/AsynchronousScalableWebApplicationsWithRealtimePersistentLongrunningConnectionsWithSignalR.aspx
SuperWebSocket
Event Streaming Frameworks
getstream.io