When I want to hack on my node app, I first start up Shadow in watch mode. Then I need to wait a bit until Shadow is done compiling, before starting the node process. Can I automate this in some way?

@grav you can try something like this:

srv=build/server.js
# run the server under node
( rm -f ${srv}; while [ 1 ]; do if [ -f ${srv} ]; then node ${srv}; else sleep 1; fi; done ) &
# watch-and-compile the server
( npx shadow-cljs watch server ) &

Ah, good idea. So simply remove the build artifact and then wait for it to show up!

at the end of the script i have a wait and run everything as background tasks. at the start of the script i have this:

trap killgroup SIGINT

killgroup(){
  echo killing...
  kill 0
}

probably i should document this somewhere

Great hack! Thanks a bunch @chris358 🙂

or use shadow-cljs node-repl and go from there 😉

@thheller So you mean use Clojure instead of Bash? Sounds tempting :-) I haven't used the shadow api much, apart from (shadow/watch :my-app). But that doesn't seem to work in a node-repl? Am I mis-reading https://shadow-cljs.github.io/docs/UsersGuide.html#node-repl?

I do not know what you read from that

you just get a blank CLJS REPL that isn't tied to your :my-app build but can still just (require '[ :as x]) and (x/main "foo" "bar") or so (emulating a regular :node-script build for example)

node-repl just manages the node process so you don't have to use hacks to wait for files to appear or so

just gives you the regular clojure-like REPL experience

probably doing something horribly wrong, but this seemed like it used to work.

now getting TypeError: ia.format is not a function in release, but works in repl. Obviously getting minified away. Any good way to avoid?

@hoppy you were probably relying on some of your :preloads loading goog.string.format

just add it to your :require in the ns

format is actually it its own "namespace". looks a bit weird but works

ok, this works. I'm not sure I understand why, or whether I need to.

but thanks

...

dont remove the first one

(ns my-app.core
  (:require [goog.string :as gstring]
            [goog.string.format]))

I know its weird .. blame the closure library

you need to because goog.string and goog.string.format format are basically 2 namespaces

but for some reason goog.string.format is not actually a namespace, only a function

but it is in its own file so it needs to be required properly

neato 😜

you are probably right though, I dug that code out of a different working project, so it was probably osmosis of some sort.

thanks again for the help

yeah it works by accident if goog.string.format was required anywhere else but its not something you should rely on so the :require fixes that

Hello! When I make a simple change to my app, it takes Shadow 3-7 seconds to recompile the change, after which the app re-renders. Is that duration normal? Or do I use too many libraries or is the changed UI namespace too large? What can I do to speed it up, so that I can change the code (add a new dom element, change button label, ...) and see the change "at once"? Thank you!!!

@holyjak that seems excessive and shouldn't be that slow. complex macros can significantly impact recompile speeds. maybe try running with shadow-cljs watch app --verbose or use the UI to see where it spends its time

I guess my shadow issues are related to the following problem logged in the browser console, which I have not seen before (on a project I haven't used for a 2-3 months): > failed to parse websocket message {:type :repl/init, :repl-state {:shadow.cljs.repl/repl-state true, :current-ns cljs.user, :repl-sources [...], :repl-actions []}} #error {:message "Invalid reader tag: :type. Reader tags must be symbols.", :data {:type :reader-exception, :ex-kind :reader-error}} Any idea what could be wrong / where to look? I have just upgraded to shadow 2.11.1, deleted node_modules and .shadow-cljs, and installed/started from scratch.

@holyjak uhm that doesn't look like 2.11.1? do you use project.clj or deps.edn and didn't upgrade there?