How to run a shell script hosted remotely from a Gradle task

Question

Say you've got a simple bash script

echo $@

Hosted it in a public repo so you can access the raw file like

https://raw.githubusercontent.com/.../test.sh

Then you can run it in a shell like

bash <(curl -s https://raw.githubusercontent.com/.../test.sh) "hello"

I want to be able to achieve this within a gradle task. I've tried:

task testScript(type: Exec) {
  workingDir projectDir
  executable "bash <(curl -s https://raw.githubusercontent.com/.../test.sh) 'hello'"
}

and

task testScript(type: Exec) {
  workingDir projectDir
  executable "bash"
  args "<(curl -s https://raw.githubusercontent.com/.../test.sh)" 'hello'
}

and

task testScript(type: Exec) {
  workingDir projectDir
  commandLine "bash", "<(curl -s https://raw.githubusercontent.com/.../test.sh)", "hello"
}

To no avail. What am I doing wrong?

Answer 1

In your original command, <(curl -s https://raw.githubusercontent.com/.../test.sh) isn't resolved by the bash command you call, but by the shell from which you call it, the actual command being executed is something like bash /dev/fd/63 "hello" .

Gradle is no shell and will just call bash with the string "<(curl -s https://raw.githubusercontent.com/.../test.sh)" as argument without further processing.

You need to find a command that doesn't need to be expanded by the shell it's being called from. For instance, handling your current command as plain text and using another shell to resolve it :

bash -c 'bash <(curl -s https://raw.githubusercontent.com/.../test.sh) hello'

In conclusion I believe the following should work :

task testScript(type: Exec) {
  workingDir projectDir
  executable "bash"
  args "-c", "bash <(curl -s https://raw.githubusercontent.com/.../test.sh) hello"
}