
mnardell
Web Development with Clojure 3rd - Shadow.cljs REPL receiving DEBUG logs (page 123)
In chapter 5, page 123 the reader of the book is instructed to start the Shadow.cljs REPL with:
$ npx shadow-cljs cljs-repl app
… upon entering that command from a terminal session (in the guestbook directory). the REPL seems to start correctly, however it becomes effectively unusable due to the repeated DEBUG level log message:
[XNIO-1 I/O-4] DEBUG io.undertow.websockets.core.request - UT025003: Decoding WebSocket Frame with opCode 1
Other than that I believe, everything seems to be running correctly. For example I can get a JS Alert to appear on the targeted browser by typing into the REPL
(js/alert "Hello")
The repeated DEBUG message makes it inconvenient working with the REPL, and I certainly would benefit from understanding how to properly configure the logging that I am seeing. I is not at al clear to me where I would find the logging configuration in the current set-up I have (I have followed the steps described in the book up to this point)
Thanks for any advice!
First Post!

mnardell
I managed to find some online discussions related to this topic, connect the dots, and I found out where the logging levels are set in a Luminous project. One will find logback.xml configurations for dev, test, prod in the env/*/resources directories. Simply adding this xml element:
<logger name="io.undertow.websockets" level="warn" />
silences the undertow DEBUG messages and makes the Shadow.cljs REPL operable. For an example of the logback.xml , have a look at:
Of course this all seems obvious to me now, but I felt rather at loss when I made this post. I suppose that is the nature of learning.
Thanks!
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