Ruby - HMAC-SHA256 example

gistfile1.rb

require 'openssl'
require 'Base64'

key = "secret-key"
data = "some data to be signed"
Base64.encode64(OpenSSL::HMAC.digest(OpenSSL::Digest::Digest.new('sha256'), key, data)).strip()

secure_hash = OpenSSL::HMAC.hexdigest('SHA256', <key>, <data>)

Note that it's also very important to define what data to sign. In the Shopify example, they sign the POST request body (which makes sense for webhooks). So make sure you figure out what data you want to sign (request path, params, user auth data, nonce, etc), such that an attacker can at most replay the call, and cannot make other calls with the request signature.

+1 for @gr8bit suggestion

@A1iAshoor's example is what Stripe is using in its libraries. In case anyone else also writing tests for your webhooks.

If you came here (like me) looking for a quick hint on how to encode hmac sha256 for Facebook's appsecret_proof parameter, this is what you are looking for:

OpenSSL::HMAC.hexdigest(OpenSSL::Digest.new('sha256'), <app_secret>, <user_access_token>)

:)

Thanks, it works like a charm.

OpenSSL::HMAC.hexdigest(OpenSSL::Digest.new('sha256'), <app_secret>, <user_access_token>)

Thanks, it worked well here too!

secure_hash = OpenSSL::HMAC.hexdigest('SHA256', <key>, <data>)

thx~

OpenSSL::HMAC.hexdigest(OpenSSL::Digest.new('sha256'), <app_secret>, <user_access_token>)

Worked perfectly for Facebook API, thank you @gr8bit