i use lein uberjar for production deployments, then java -jar [...].jar. I have a web app where you can upload images. they get put in $proj_dir/resources/images. for the longest time i couldn’t figure out why images that were uploaded during a production deployment wouldn’t show up, but when run in dev mode, they did show up. then, i jar tf [...].jar‘d the uberjar. lein uberjar includes all the images in ./resources/images. so when the production app is running, images are correctly being saved to disk, but because they’re not in the uberjar, they don’t show up in my webapp. question: how do i get what i want? is there an option in project.clj? i’m not very familiar with project.clj or lein. i want to be able to read from that directory when running my production app.

i diagnosed the problem after realizing that i can see all previously-uploaded images after i lein uberjar. and i can see all images--no matter what--when running via lein repl

make sure that resource path is on your classpath

or use file instead of resource based operations to find the images

so instead of java -jar [...].jar use java -cp [...].jar:resources my-app.main

(for the resources option, which is the most convenient over all)

where you substitute your actual ns containing -main for my-app.main of course

when you say “make sure that resource path is on your classpath”: my :profiles options for :uberjar are:

{:omit-source true
             :aot :all
             :uberjar-name "conus.jar"
             :source-paths ["env/prod/clj"]
             :resource-paths ["env/prod/resources"]}

i’ll look up the difference between java -cp and java -jar

your uberjar doesn't know anything about your profiles

the directory is not inside the jar, so java doesn't use it

that config only affects what goes in the jar when you build it

the difference between -cp and -jar is that one of them lets you specify a custom class path (and then requires manually saying which class to run, since there's no one jar to use as a default)

ah, so adding "resources" into the the :resource-paths won’t help, because the running jar can’t read at run-time from resources/images? sorry to need to be so explicit; this is all new to me.

the running jar doesn't use your lein config at all

lein is a tool that builds a jar, java at runtime knows nothing about the config lein used

the jar can read from resources/images, if you tell it to, but just having it in lein config doesn't do anything to change the behavior of the runtime jar executed by java

which is why you have to configure java's classpath to see the directory

oh right; i’m running java not lein to run the app. gotcha.

thanks @noisesmith java -cp works.

another fun trick is that you can run your uberjar to get a repl that can use all of your deps and namespaces

java -cp my.uber.jar clojure.main - optionally rlwrap java -cp my.uber.jar clojure.main on a *nix to get command line editing and history too

in a pinch I've used this to speed up debugging issues on remote servers

oh that’s nice! saved.

What is java -cp?

it's the java command, with an argument specifying the class path (where it looks to find things)

I see

clojure is a java library, you can create a jar that runs directly from java without needing any other dependencies on your server

I just use -jar

right, if you follow the conversation back, @mfm needed to read some things from disk, and others from inside the jar, with the same code, and setting cp simplifies that

Onde

I see

Thanks