From 051581fe2e2b7cbca53b5ce9b81a64b018296739 Mon Sep 17 00:00:00 2001
From: Robert Keresnyei <rk@nemron.com>
Date: Tue, 9 Jul 2024 19:04:37 +0200
Subject: [PATCH] Evaluate host block only if needed

---
 lib/rack/canonical_host.rb          |  9 +--------
 lib/rack/canonical_host/redirect.rb | 12 +++++++++---
 2 files changed, 10 insertions(+), 11 deletions(-)

diff --git a/lib/rack/canonical_host.rb b/lib/rack/canonical_host.rb
index 91f4605..f5d0210 100644
--- a/lib/rack/canonical_host.rb
+++ b/lib/rack/canonical_host.rb
@@ -17,8 +17,7 @@ def call(env)
 
       return request.bad_request_response unless request.valid?
 
-      host = evaluate_host(env)
-      redirect = Redirect.new(env, host, options)
+      redirect = Redirect.new(env, host, options, &block)
 
       if redirect.canonical?
         app.call(env)
@@ -33,11 +32,5 @@ def call(env)
     attr_accessor :host
     attr_accessor :options
     attr_accessor :block
-
-  private
-
-    def evaluate_host(env)
-      block and block.call(env) or host
-    end
   end
 end
diff --git a/lib/rack/canonical_host/redirect.rb b/lib/rack/canonical_host/redirect.rb
index 757de9e..ed84761 100644
--- a/lib/rack/canonical_host/redirect.rb
+++ b/lib/rack/canonical_host/redirect.rb
@@ -15,12 +15,13 @@ class Redirect
         </html>
       HTML
 
-      def initialize(env, host, options={})
+      def initialize(env, host, options={}, &block)
         self.env = env
         self.host = host
         self.ignore = Array(options[:ignore])
         self.conditions = Array(options[:if])
         self.cache_control = options[:cache_control]
+        self.block = block
       end
 
       def canonical?
@@ -39,6 +40,7 @@ def response
       attr_accessor :ignore
       attr_accessor :conditions
       attr_accessor :cache_control
+      attr_accessor :block
 
     private
 
@@ -74,15 +76,19 @@ def ignored?
       end
 
       def known?
-        host.nil? || request_uri.host == host
+        evaluated_host.nil? || request_uri.host == evaluated_host
       end
 
       def new_url
         uri = request_uri.dup
-        uri.host = host
+        uri.host = evaluated_host
         uri.normalize.to_s
       end
 
+      def evaluated_host
+        @evaluated_host ||= block and block.call(env) or host
+      end
+
       def request_uri
         @request_uri ||= Addressable::URI.parse(Rack::Request.new(env).url)
       end