Modularize handlers

spec/handler_spec.cr

@@ -120,4 +120,17 @@ describe "Handler" do
     client_response = call_request_on_app(request)
     client_response.body.should eq "OnlyExcludePost"
   end
+
+  it "adds a handler at given position" do
+    post_handler = PostOnlyHandler.new
+    add_handler post_handler, 1
+    Kemal.config.handlers[1].should eq post_handler
+  end
+
+  it "assigns custom handlers" do
+    post_only_handler = PostOnlyHandler.new
+    post_exclude_handler = PostExcludeHandler.new
+    Kemal.config.handlers = [post_only_handler, post_exclude_handler]
+    Kemal.config.handlers.should eq [post_only_handler, post_exclude_handler]
+  end
 end

src/kemal/config.cr

@@ -17,6 +17,7 @@ module Kemal
     property host_binding, ssl, port, env, public_folder, logging, running,
       always_rescue, serve_static : (Bool | Hash(String, Bool)), server, extra_options,
       shutdown_message
+    getter custom_handler_position
 
     def initialize
       @host_binding = "0.0.0.0"
@@ -59,9 +60,14 @@ module Kemal
       HANDLERS
     end
 
-    def add_handler(handler : HTTP::Handler | HTTP::WebSocketHandler)
+    def handlers=(handlers : Array(HTTP::Handler))
+      clear
+      handlers.each { |handler| HANDLERS << handler }
+    end
+
+    def add_handler(handler : HTTP::Handler | HTTP::WebSocketHandler, position = Kemal.config.custom_handler_position)
       setup
-      HANDLERS.insert @custom_handler_position, handler
+      HANDLERS.insert position, handler
       @custom_handler_position = @custom_handler_position + 1
     end
 

src/kemal/helpers/helpers.cr

@@ -8,8 +8,8 @@
 # - Kemal::StaticFileHandler
 # - Here goes custom handlers
 # - Kemal::RouteHandler
-def add_handler(handler)
-  Kemal.config.add_handler handler
+def add_handler(handler, position = Kemal.config.custom_handler_position)
+  Kemal.config.add_handler handler, position
 end
 
 # Sets public folder from which the static assets will be served.