Best way to specify root certificate for Issuer.discover

[tacallah]

WORKING SOLUTION
From DOS shell, run this command:

SET NODE_EXTRA_CA_CERTS=root.pem

Run this js code with Node.js from same DOS shell:

import { Issuer } from "openid-client";

// Discover the OpenID Connect issuer
Issuer.discover("https://my-issuer.com", httpsAgent)
.then(issuer => {
console.log("Discovered issuer %s", issuer.issuer);
})
.catch(err => {
console.error("Error discovering issuer", err);
});

The following result displays in window:

Discovered issuer https://my-issuer.com/app

ALTERNATIVE
Is the above solution the best way? I was hoping to read the cert file and provide it to Issuer.discover in the same way the cert file is specified in an options object and passed to https. The below code does not work, but this what I'd like to do:

import { Issuer } from "openid-client";
import { Agent } from "https";
import { readFileSync } from "fs";

// Read the certificate file
const rootCertificate = readFileSync("root.pem");

// Create an https agent with the root certificate
const httpsAgent = new Agent({
ca: rootCertificate,
rejectUnauthorized: true
});

// Discover the OpenID Connect issuer
Issuer.discover("https://my-issuer.com", httpsAgent)
.then(issuer => {
console.log("Discovered issuer %s", issuer.issuer);
})
.catch(err => {
console.error("Error discovering issuer", err);
});

Is something like that possible with openid-client? Is there a better way to specify the root certificate for Issuer.discover?

Thanks in advance!