Accessing Command Line Arguments
Evan Hicks
—The Problem
Sometimes in your Node app you will want to access the command line arguments that were passed in when running your script. The usage message for Node says that passing arguments are possible.
$ node -h Usage: node [options] script.js [arguments]
The Solution
Command line arguments passed into your script are available using process.argv in your code. This is an array that stores all the details of how your script was run, including the executable used and the path to the current script.
Please see the documentation on this variable. Below is an example of what the process.argv looks like.
// This is example.js process.argv.forEach((val, idx) => { console.log(`${idx}: ${$val}`); });
$ node example.js arg1 arg2=test 0: /usr/bin/local/node 1: /Users/myuser/example.js 2: arg1 3: arg2=test
There are also lots of packages that can be used to help parse different arguments for use in your app, such as argparse.
Further Reading
If you’re looking to get a deeper understanding of how Node.js application monitoring works, take a look at the following articles:
- SentryWorkshop: Debugging your Node.js Project With Sentry
- Syntax.fmListen to the Syntax Podcast
- Community SeriesIdentify, Trace, and Fix Endpoint Regression Issues
- ResourcesBackend Error Monitoring 101
- Listen to the Syntax Podcast
![Syntax.fm logo]()
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