pass parameters to bash script through npm run

Question

I'm new to writting bash script and I have a npm package that I created https://www.npmjs.com/package/comgen

Bash

days=3
hours=24
minutes=60
totalNumberOfCommits=3
lenghtOfTime=$((days*hours*minutes))
arrayOfCommits=$(shuf -i 1-$lenghtOfTime -n $totalNumberOfCommits | sort -r -n)
for index in $arrayOfCommits
 do
 randomMessage=$(cat /dev/urandom | tr -dc 'a-zA-Z0-9' | fold -w 32 | head -n 1) 
 git commit --allow-empty --date "$(date -d "-$index minutes")" -m "$randomMessage"
 done 
git push origin master

You run it like this npm run comgen I want it to run like this:

npm run comgen -days "x number of days" -totalNumberOfCommits "x number of commits"

Package.json

"scripts": {
 "comgen": "commit-generator.sh"
 },

Where the number of days and the total of commits passed will replace the number in the variables I have in the bash script.

I read this SO questions before postins my own: https://unix.stackexchange.com/questions/32290/pass-command-line-arguments-to-bash-script

Answer 1

I'm not sure how exactly npm works, but from my experience I guess that command-line arguments are passed directly to the called executable (binary or script). This means your script is actually called like

/path/to/comgen -days "x number of days" -totalNumberOfCommits "x number of commits"

Now it's pure Bash stuff to parse the cmdline arguments. You evaluate an option and decide what the next value is:

days=3
hours=24
minutes=60
totalNumberOfCommits=3
while [ $# -ne 0 ]; do
 case "1ドル" in
 "-d"|"-days") days=2ドル; shift 2;;
 "-tc"|"-totalNumberOfCommits") totalNumberOfCommits=2ドル; shift 2;;
 # "-x"|"-xx"|"-xxx") : Process another option; shift 2;;
 *) break;;
 esac
done
lenghtOfTime=$((days*hours*minutes))
... rest of the code

• Patricio Vargas: All I have to do know is now go to pass variables to the npm run comgen -d 5 -tc 10
• Patricio Vargas: I got to the point where I can run this commit-generator.sh -d 4 -tc 10 in the terminal. Now, when I want to do npm run comgen -d 5 -tc 10 i get commit-generator.sh -d 1ドル -tc 2ドル "1" "10" in my package.json I have "scripts": { "comgen": "commit-generator.sh -d 1ドル -tc 2ドル " }
• Patricio Vargas: i figured it out. My problem is that i need to pass the parameters with out the "-" and change the name in the bash script to be just d,tc,etc

Answer 2

Try this

package.json

"scripts": {
 "comgen": "commit-generator.sh"
 },

commit-generator.sh

 #!/bin/bash 
echo $npm_config_days
echo $npm_config_hours

and finally in terminal

npm run comgen --days=foo --hours=bar

output:

> commit-generator.sh
foo
bar