Clojurians Log v2

It depends on what you want. Routing doesn't really have to have much do with SSE (or WS). Once the request is routed, your handled can do what ever you want. Then handling the SSE response only depends on your http adapter (http-kit or whatever.)

Though yes, this means that Muuntaja and other Reitit middleware won't see the SSE messages. But it doesn't matter much, you just handle encoding those messages in the code yourself.

I think you can even get the active Muuntaja instance from the Reitit request and use that.

In general, I don't know if I would recommend SSE now. Both Clj http server and JS client support is somewhat limited.

Ring-jetty-adapter tests have some SSE test cases: https://github.com/ring-clojure/ring/blob/master/ring-jetty-adapter/test/ring/adapter/test/jetty.clj#L547-L574

It just needs to use the async ring handler arity and then return a response implementing StreamableResponseBody which can then write messages to the response connection.

Hmm, I’ve switched ring.adapter.jetty9 to async mode and I’m seeing Reitit call my handler with a single argument rather than three though. https://github.com/sunng87/ring-jetty9-adapter I know async is in place as a couple of my custom middleware weren’t setup for async, which triggered exceptions. I assumed there wasn’t async support inside the default execution path of Reitit because of this arity error I ran into.

["/stream"
 {:name :app.route/stream
  :get
  {:handler
   (fn [& args]
     (throw (ex-info "Stream!" {:n (count args) :args args})))}}]

[nrepl  ] 09:20:08.109 INFO  app.web {:msg "Uncaught exception processing request.", :request-method :get, :uri "/stream", :exception #error {
[nrepl  ]  :cause "Stream!"
[nrepl  ]  :data {:n 1, :args ({:reitit.core/match #reitit.core.Match{:template "/stream" […]

https://caniuse.com/eventsource looks good across the clients I need to support, and ring-jetty9-adapter supports async so I’d expect this to be a relatively simple solution to pushing updates to a client.

long time don't use it ... but maybe the :no-doc keyword?

Yep, documented here https://github.com/metosin/reitit/blob/master/doc/ring/openapi.md#openapi-data