Intro
So we installed NodeJS on our machine.
Now we want to write a simple script, run it from the terminal & use some commandline arguments.
Write a simple script
- Open your terminal
- Create a file named
index.js
:
touch index.js
- Add
console.log('Hello')
into it:
echo "console.log('Hello')" > index.js
Run it from the terminal
- Run it:
node index.js
Use commandline arguments
- Update
index.js
to use the commandline arguments and print them:
echo "const args = process.argv" > index.js
echo "console.log(args)" >> index.js
- Run it with an argument:
node index.js miku86
- We are seeing an array with 3 elements:
[
'/usr/bin/node',
'/home/miku86/index.js',
'miku86'
]
args[0] is the path to the executable file,
args[1] is the path to the executed file,
args[2] is the additional commandline argument from step 2.
So if we want to use our additional commandline argument,
we can use it like this in a JavaScript file:
console.log(args[2])
Further Reading
Node process.argv documentation
Questions
- Do you use the native
process
or some libraries likeyargs
? Why?
Top comments (3)
Cool article. Last time I had to do a project with node on the terminal I used meow. It helps with flag creation and automatically creates a
--help
flag.You can also use yargs for that. I haven't tried meow yet but seems intriguing.
Hey André & Shawon,
thanks for your feedback.
I usually use yargs & I will check out meow.
After looking at npm trends, I will also take a look at commander.