golang build constraints exclude all Go files in

Question

I build a simple "Hello, World" wasm app like:

GOARCH=wasm GOOS=js go build -o lib.wasm main.go

All is well. But then I want to test my code in my local (Linux) environment. So I change it to a pretty standard:

package main

import "fmt"

func main () {
    fmt.Println("test")
}

And do a simple:

go run .

but now I get:

package xxx: build constraints exclude all Go files in xxx

I understand that if I specify a wasm build, I can't expect to run it locally. But I'm not trying to do a wasm build anymore. There are no build constraints in my .go source file, and my go.mod file just has the package and go version.

If I copy these file to a new directory and only do the go run . without the wasm build - all is good.

And if I do:

go build filename.go

it works properly.

It's like something "remembers" that this directory was supposed to be built with wasm - but I cant find what/where.

Is there a cache or something elsewhere that's remembering some build settings that I need to clear? I've tried go clean and go clean -cache - no luck!

Answer 1

I understand that I can just split up the big list file with something like "split" and then set the script to background the task with &, but I cannot wrap my head around that part.

Put the stuff to execute in a function. Then use GNU parallel or xargs.

doit() {
   # command in an array for comments
   cmd=(
        curl --silent --request GET
        --url "https://api.example.com/$1"
        # check your scripts with shellcheck
        --header "authorization: Bearer $auth_key"
        --data '{}'
   )
   # execute it and store in variable
   tmp=$("{$cmd[@]}")
   # output in a single call, so that hopefully buffering does not bite us that much
   # if it does, use a separate file for each call
   # or use GNU parallel
   printf "%s\n" "$tmp"
}
export auth_key   # export needed variables
export -f doit    # export needed functions

# I replaced /home/debian by ~
# run xargs that runs bash that runs the command with passed argument
# see man xargs , man bash
xargs -d '\n' -P 1000 -n 1 bash -c 'doit "$@"' _ < ~/names.list > ~/results.list

of bursting the ~10,000 calls in batches of 1 or 2 thousand.

You would have to write a manual loop for that:

trap 'kill $(jobs -p)' EXIT  # kill all jobs on ctrl+c
n=0
max=1000
# see https://mywiki.wooledge.org/BashFAQ/001
while IFS= read -r line; do
   if ((++n > max)); then
       wait  # wait for all the currently running processes
       n=0
   fi
   doit "$line" &
done < ~/names.list > ~/results.list
wait

---

Problems with your script:

• Use shellcheck to check your scripts
• do not use for i in $(cat..) also do not use it in the form of tmp=$(cat ..); for i in $tmp. See https://mywiki.wooledge.org/BashFAQ/001
• Users is not an array
• $n and $auth_key are not quoted. In particular, auth_key="***" is replaced by all your files in current directory.
• your second script does not wait for them.