Last Updated: May 28, 2022
· Lex S

Generate a self-signed X509 certificate with ruby

Create a public X509 certificate called 'certificate.pem' and a private rsa key called 'private_key.pem':
require "openssl"

key = 4096

name = OpenSSL::X509::Name.parse '/CN=nobody'

cert =

cert.version = 2

cert.serial = 0

cert.not_before =

cert.not_after = + 606024364.251

cert.publickey = key.publickey

cert.subject = name

cert.issuer = name

cert.sign key,'SHA256')

open 'certificate.pem', 'w' do |io| io.write cert.to_pem end

open 'privatekey.pem', 'w' do |io| io.write key.topem end

The ruby openssl docs have other great examples.

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