Extract public key from private key pem using only nodejs/javascript

javascript, node.js, pem

Solution

from the node-forge documentation

pem = '-----PRIVATE KEY ----- [...]'
pki = require('node-forge').pki
privateKey = pki.privateKeyFromPem(pem)
publicKey  = pki.setRsaPublicKey(privateKey.n, privateKey.e)
console.log(pki.publicKeyToPem(publicKey))

Problem

Using `nodejs` and only javascript, how do I extract a public key from a private key pem? The private key that I have in hand is a PEM formatted private key; I'd like to extract the public key so I can distribute it to collaborators. I regularly use the pure javascript `node-forge` module but have not yet discovered how to extract the public key from the private key. I am also aware of, and presently use the `ursa` module to accomplish this; but I would like a pure javascript or pure nodejs solution if available.

Original source