Better method naming, HMAC verification and generation fixes, example of using HMAC in cookies

examples/cookies-hmac/cookie.ru

@@ -0,0 +1,27 @@
+# frozen_string_literal: true
+
+$LOAD_PATH.unshift("#{File.dirname(__FILE__)}/lib")
+require 'securerandom'
+require 'landline'
+require 'landline/util/cookie'
+require 'irb'
+
+KEY = SecureRandom.base64(64).freeze
+
+app = Landline::Server.new do
+  get "/set-cookie" do
+    cookie "test", (rand * 500).floor.to_s, { hmac: KEY }
+    header "content-type", "text/plain"
+    "Cookie set! Visit /get-cookie to view it"
+  end
+  get "/get-cookie" do
+    header "content-type", "text/plain"
+    if request.cookies.dig('test', 0)&.verify(KEY)
+      "Cookie is valid and generated by server"
+    else
+      "Cookie either doesn't exist or is forged"
+    end
+  end
+end
+
+run app

examples/cookies-hmac/lib

@@ -0,0 +1 @@
+../../lib

examples/cookies-hmac/readme.txt

@@ -0,0 +1,3 @@
+shows basic usage of unsigned cookies
+
+please note that this does not sign cookies.

lib/landline/response.rb

@@ -26,7 +26,7 @@ module Landline
     def finalize
       @cookies.each do |_, cookie_array|
         cookie_array.each do |cookie|
-          add_header("set-cookie", cookie.to_s)
+          add_header("set-cookie", cookie.finalize)
         end
       end
       [@status, @headers, @body]

lib/landline/util/cookie.rb

@@ -44,7 +44,7 @@ module Landline
 
     # Convert cookie to "Set-Cookie: " string representation.
     # @return [String]
-    def to_s
+    def finalize
       sign(@hmac, algorithm: @algorithm, sep: @sep) if @hmac
       ParserCommon.make_value(
         "#{key.to_s.strip}=#{value.to_s.strip}",
@@ -62,7 +62,8 @@ module Landline
 
     # Convert cookie to "Cookie: " string representation (no params)
     # @return [String]
-    def to_short
+    def finalize_short
+      sign(@hmac, algorithm: @algorithm, sep: @sep) if @hmac
       "#{key.to_s.strip}=#{value.to_s.strip}"
     end
 
@@ -103,6 +104,8 @@ module Landline
     # @return [Hash{String => Cookie}]
     def self.from_cookie_string(data)
       hash = {}
+      return hash if data.nil?
+
       data.split(";").map do |cookiestr|
         key, value = cookiestr.match(/([^=]+)=?(.*)/).to_a[1..].map(&:strip)
         cookie = Cookie.new(key, value)