Hello,

Thanks to the efforts of Ondrej Pokorny and some sponsored work by the FPC/Lazarus foundation, FCL-Web has received some updates:

- Improvements in fcl-net, basically a Select() call has been added to the socket stream, on all platforms that support this.

- Possibility to keep connections open in the HTTP Server (keep-alive).

- A HTTP client connection pool, for parallel downloading.

- HTTP Client Downloads can now be canceled.

- New threading model for the FPC HTTP server:
- No threading
- One thread per request/connection
- Thread pool, distributing requests over available threads.

- The thread pool functionality is in a separate unit, available for other things as well...

- Interceptors in the HTTP router:
In the HTTP router you can now register interceptors. These will be run before/after the request is dispatched to the correct handler.

Interceptors can cancel further handling of a request: This allows you to implement e.g. authentication, logging etc. in an orthogonal manner to normal request handling.

- The FPC HTTP server can now handle Connection: upgrade using registered upgrade handlers. This can be used for websocket (see below) and later HTTP/2 handling.

- FPC has now native support for the websocket protocol: both client and server are supported. Native chat client/server demos are included, and a pas2js client for use in the browser is also available. (SSL support is there but still needs testing)

- The websocket protocol support can be attached to the HTTP server. That means you can initiate a websocket connection on the same port as the HTTP server is listening; the HTTP server will hand off the connection to the websocket server using the upgrade mechanism. A server demo is included as well.

Attached a small screenshot of the websocket-based chat program in pas2js.

Enjoy,

Michael.
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El 1/9/21 a les 13:06, Michael Van Canneyt via lazarus ha escrit:

Having not seen the implementation, my questions are:

1) existing code will still work unmodified?
2) specifically the hack for server-sent events I mentioned here https://lists.lazarus-ide.org/pipermail/lazarus/2020-June/238089.html will still work?

1) I suppose is a given ;-), 2) I ask because you only mentioned websockets and not server-sent events.

Bye

Yes.

2) specifically the hack for server-sent events I mentioned here https://lists.lazarus-ide.org/pipermail/lazarus/2020-June/238089.html will still work?

The pastebin link is down ?

1) I suppose is a given ;-), 2) I ask because you only mentioned websockets and not server-sent events.

Server events are normally done using HTTP/2, and this is planned.

I can't promise your code will still run, but since the server was modified to keep connections alive indefinitely, I suppose that you should now be able to handle server events even easier with the upgrade mechanism;

It's just a matter of deciding to 'upgrade' depending on the URL & headers in the initial request. In case you try to take a shot at it and you need help implementing it, let me know...

Michael.

El 1/9/21 a les 17:14, Michael Van Canneyt via lazarus ha escrit:

it's still there but it requires a login, anyway, I copied it here

https://pastebin.com/gyqS83Nt

well, I'm successfully using it over http 1.1 (I suppose that's the only protocol currently supported by fpWeb)

It'd be enough for it to continue working as it is....

It's just a matter of deciding to 'upgrade' depending on the URL & headers in the initial request. In case you try to take a shot at it and you need help implementing it, let me know...

...when I have to modify the project using the above hack, though this could happen next month, next year or never. In that case I could try to adapt the code to the new paradigm but, as I said, I'd prefer it to continue working as it is ;-)
(most probably because the http server part won't be the part I'll need to modify).

Bye