add bin/hook

1 files changed, 54 insertions, 0 deletions

diff --git a/bin/hook/fire.rb b/bin/hook/fire.rb
new file mode 100755
index 0000000..5cd6022
--- /dev/null
+++ b/bin/hook/fire.rb
@@ -0,0 +1,54 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+#
+# bin/hook/fire.rb: trigger deploy webhook.
+#
+# Requires that the following environment variables are set:
+# 
+# * HOOK_URL: Webhook URL
+# * HOOK_HMAC_KEY: Hook HMAC-SHA256 key.
+#
+
+require 'openssl'
+require 'json'
+require 'time'
+require 'uri'
+require 'net/http'
+require 'pp'
+
+# get hook URL and HMAC key
+hook_url = ENV.fetch('HOOK_URL')
+key = ENV.fetch('HOOK_HMAC_KEY')
+
+# get name of HMAC header, or default to X-Hub-Signature if unspecified
+header_name = ENV.fetch('HOOK_HMAC_HEADER', 'X-Hub-Signature')
+
+# build body
+body = JSON({
+  # current timestamp, in ISO8601/RFC3339 format
+  time: Time.now.iso8601,
+
+  # random nonce
+  nonce: OpenSSL::Digest::SHA256.hexdigest(OpenSSL::Random.random_bytes(32)),
+})
+
+# calculate hmac
+hmac = OpenSSL::HMAC.hexdigest('SHA256', key, body)
+
+# parse uri
+uri = URI.parse(hook_url)
+
+# build request
+req = Net::HTTP::Post.new(uri.path)
+# req[header_name] = hmac
+req[header_name] = 'sha256=%s' % [hmac]
+req['Content-Type'] = 'application/json'
+req.body = body
+
+# build connection
+http = Net::HTTP.new(uri.host, uri.port)
+http.use_ssl = true
+
+# send request
+pp http.request(req)