request.rb

# typed: strict
# frozen_string_literal: true

module ShopifyAPI
  module Webhooks
    class Request
      extend T::Sig
      include Utils::VerifiableQuery

      sig { override.returns(String) }
      def hmac
        Digest.hexencode(Base64.decode64(T.cast(shopify_header("hmac-sha256"), String)))
      end

      sig { returns(String) }
      def topic
        T.cast(shopify_header("topic"), String)
      end

      sig { returns(String) }
      def shop
        T.cast(shopify_header("shop-domain"), String)
      end

      sig { returns(String) }
      def api_version
        T.cast(shopify_header("api-version"), String)
      end

      sig { returns(String) }
      def webhook_id
        T.cast(shopify_header("webhook-id"), String)
      end

      sig { override.returns(String) }
      def to_signable_string
        @raw_body
      end

      sig { returns(T::Hash[String, T.untyped]) }
      def parsed_body
        JSON.parse(@raw_body)
      end

      sig { params(raw_body: String, headers: T::Hash[String, T.untyped]).void }
      def initialize(raw_body:, headers:)
        # normalize the headers by forcing lowercase, removing any prepended "http"s, and changing underscores to dashes
        headers = headers.to_h { |k, v| [k.to_s.downcase.sub("http_", "").gsub("_", "-"), v] }

        missing_headers = []
        ["topic", "hmac-sha256", "shop-domain"].each do |name|
          unless headers.key?("shopify-#{name}") || headers.key?("x-shopify-#{name}")
            missing_headers << "shopify-#{name} or x-shopify-#{name}"
          end
        end
        unless missing_headers.empty?
          raise Errors::InvalidWebhookError,
            "Missing one or more of the required HTTP headers to process webhooks: #{missing_headers}"
        end

        @headers = headers
        @raw_body = raw_body
      end

      private

      sig { params(name: String).returns(T.untyped) }
      def shopify_header(name)
        @headers["shopify-#{name}"] || @headers["x-shopify-#{name}"]
      end
    end
  end
end