Node.js x509.issuerCertificate Property

The x509.issuerCertificate is an inbuilt application programming interface of class X509Certificate within crypto module which is used to get the issuer certificate or undefined if the issuer certificate is not available.

Syntax:

const x509.issuerCertificate

Parameters: This property does not accept any arguments as a parameter.

Return Value: This property returns the issuer certificate or undefined if the issuer certificate is not available.

How to generate a Public certificate?

Public certificate Open notepad and copy-paste the following key and save the file as public-cert.pem

-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Example 1:

index.js

// Node.js program to demonstrate the
// x509.issuerCertificate function

// Importing crypto module
const {X509Certificate} = require('crypto')

// Importing fs module
const fs = require('fs')

// getting object of a PEM encoded X509 Certificate.
const x509 = new X509Certificate(fs.readFileSync('public-cert.pem'));

// getting issuerCertificate included in this certificate.
// by using x509.issuerCertificate function
const value = x509.issuerCertificate

// display the result
console.log("issuerCertificate :- " + value)

Run the index.js file using the following command.

node index.js

Output:

issuerCertificate :- undefined

Example 2:

index.js

// Node.js program to demonstrate the
// x509.issuerCertificate function

// Importing crypto module
const {X509Certificate} = require('crypto')

// Importing fs module
const fs = require('fs')

// display the result
console.log("issuerCertificate :- " + (new X509Certificate(
             fs.readFileSync('public-cert.pem'))).issuerCertificate)

Run the index.js file using the following command.

node index.js

Output:

issuerCertificate :- undefined

Reference: https://nodejs.org/dist/latest-v15.x/docs/api/crypto.html#crypto_x509_issuercertificate