I call my node.js application with
node index.js a=5
I want to use the value '5' directly as an environment variable in my code like
const myNumber = process.env.a
(like stated here).
If I try the above, 'MyNumber' is undefinded on runtime.
Solution
- Linux:
a=5 node index.js
- Windows (Powershell):
$env:a="5";node index.js
CodePudding user response：
When doing node index.js a=5, a=5 is an argument for node, as index.js is.
If you want to pass an environment variable, you must specify it before node command : a=5 node index.js.
The node process.env is populated with your bash environment variables.
CodePudding user response：
a=5 is an argument to your script not an environment variable. to access the argument in the script use process.argv
https://nodejs.org/en/knowledge/command-line/how-to-parse-command-line-arguments/
CodePudding user response：
Right now, when you run the following command, it is setting an argument for Node.js (your index.js file).
$ node index.js a=5
You can access this using the code below. It will simply return the value the first value passed in.
// node index.js a=5
process.argv[2]
You need to get the 2nd index, as the first 2 are just command line ones.
If you want to pass an environment variable, you need to set it before running the command, as so.
$ a=5 node index.js
You can then access it with process.env, as you have already specified.