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Anyone know of any examples of cool cases where websockets have been used? (Maybe other than games.) I feel like in most cases I see them used the latency gained is basically added back with bloat in other parts.
I just launched this site with websockets: https://hackernews.pro Websockets used for updating Story/Comment data, and User presence
Earlier quoted context omitted.
What is the right way to handle authentication over web sockets?
If I understand correctly, websockets is a thin layer on TCP that does buffer data so that the application get the whole message instead of chunks. I recommend using wss to secure the websocket so that it can't be hijacked, then you don't need to send a token in each message and can do an application layer handshake once. Basically the first websock message from the client would be an authentication message with a pa…
The first websocket message is the original request, which will have the users cookies / headers where your session information / bearer token should live.
HTTP servers have already solved traffic management, load balancing, scaling up and down, zero downtime deployments, A/B tests and experimentation and lots more to such a degree that we don't have to even think about them anymore. All of these problems come to the forefront again when you have to scale websocket connections beyond a single server.
Hi HN! I'm Alex, and I've been researching and writing about WebSockets for a while now. I'm the author of the recently released WebSocket Handbook. AMA about the WebSocket tech, the realtime web, Ably or anything related to Liverpool FC.
What is the right way to handle authentication over web sockets?
Before going all-in on websockets I'd like to caution people to thoroughly consider the server-side scaling challenges that come with it. HTTP servers have already solved traffic management, load balancing, scaling up and down, zero downtime deployments, A/B tests and experimentation and lots more to such a degree that we don't have to even think about them anymore. All of these problems come to the forefront again w…
When a message comes into an instance, you push it to Redis and have all of your other instances subscribed to it. Messages sync in real-time and the experience is transparent.
I teach the technique here: https://cheatcode.co/courses/how-to-implement-real-time-data...
1 - A websocket "frame" has a variable-length header. Client->Server the header can be 6, 8 or 14 bytes. Server->Client it can be 2, 4 or 10. This is to support payloads 2 - Frames can be fragmented to support streaming (where the sender or possibly a proxy doesn't know/want to buffer the entire response ahead of time). I feel like this is unnecessary in 99% of the cases. It wouldn't be so annoying..except control frames can be interspersed within fragmented frames. This is so that you can send a "ping" while streaming a large message over multiple fragments. Why didn't they just use one of those reserved bits for this?
3 - Client->Server payload is masked with 4 bytes (bitwise xor) so every message your server gets has to be unmasked.
In case the email collection form gets hugged to death, here's a mirror https://web.archive.org/web/20220111162712/https://files.abl... In our experience, many enterprise networks/vpns/firewalls still break websocket connections even when using wss, and it should not be used as the only communication channel even if you target evergreen browsers.
Disclaimer: I work for Ably. I agree in principle, so the libraries that handle websockets and also fallback transports using comet (eg SocketIO) are still widely used for that reason, and the commercial pub/sub service providers generally also support comet fallbacks. However, we now find that it is really very rare that clients are unable to use wss.
HN is generally reserved for interesting articles. Not self promoting your services with a cookie cutter email harvester for your drip campaign.
I bit and got the book, hoping for something interesting. It’s more or less the documentation on MDN or a WS library docs rephrased. Finally, after 60 pages of docs I can Google, there’s a section called “Scaling Websockets”, which is an interesting and challenging topic. Turns out it’s one paragraph long, saying - “Yeah it’s hard. You should consider using Ably. Next book will cover it.” Shameful.
It's good that you are interested in Scaling WebSockets, because that is the chapter I am writing now! I hope to get it live in a couple of weeks, once it is I can send you the new version.
Anyone know of any examples of cool cases where websockets have been used? (Maybe other than games.) I feel like in most cases I see them used the latency gained is basically added back with bloat in other parts.
Anyone know of any examples of cool cases where websockets have been used? (Maybe other than games.) I feel like in most cases I see them used the latency gained is basically added back with bloat in other parts.
Whether this qualifies as a 'cool' case is probably subjective, but it is important in practice.
I'm not sure if it's as widespread, but many exchanges use websockets in the front-end to make the same data available to the site users without frequent polling.