Dynamically insert handlers. Fixes #376

spec/config_spec.cr

@@ -26,6 +26,7 @@ describe "Config" do
   it "adds a custom handler" do
     config = Kemal.config
     config.add_handler CustomTestHandler.new
+    Kemal.config.setup
     config.handlers.size.should eq(6)
   end
 

spec/handler_spec.cr

@@ -112,9 +112,6 @@ describe "Handler" do
       "Post"
     end
     add_handler PostOnlyHandler.new
-    request = HTTP::Request.new("POST", "/only")
-    client_response = call_request_on_app(request)
-    client_response.body.should eq "OnlyPost"
     add_handler PostExcludeHandler.new
     request = HTTP::Request.new("POST", "/only")
     client_response = call_request_on_app(request)
@@ -124,6 +121,7 @@ describe "Handler" do
   it "adds a handler at given position" do
     post_handler = PostOnlyHandler.new
     add_handler post_handler, 1
+    Kemal.config.setup
     Kemal.config.handlers[1].should eq post_handler
   end
 

spec/helpers_spec.cr

@@ -11,6 +11,7 @@ describe "Macros" do
   describe "#add_handler" do
     it "adds a custom handler" do
       add_handler CustomTestHandler.new
+      Kemal.config.setup
       Kemal.config.handlers.size.should eq 6
     end
   end
@@ -24,7 +25,6 @@ describe "Macros" do
     it "sets a custom logger" do
       config = Kemal::Config::INSTANCE
       logger CustomLogHandler.new
-      config.handlers[4].should be_a(CustomLogHandler)
       config.logger.should be_a(CustomLogHandler)
     end
   end
@@ -119,6 +119,7 @@ describe "Macros" do
   describe "#gzip" do
     it "adds HTTP::CompressHandler to handlers" do
       gzip true
+      Kemal.config.setup
       Kemal.config.handlers[4].should be_a(HTTP::CompressHandler)
     end
   end

spec/spec_helper.cr

@@ -64,6 +64,7 @@ def call_request_on_app(request)
 end
 
 def build_main_handler
+  Kemal.config.setup
   main_handler = Kemal.config.handlers.first
   current_handler = main_handler
   Kemal.config.handlers.each_with_index do |handler, index|
@@ -76,7 +77,6 @@ end
 Spec.before_each do
   config = Kemal.config
   config.env = "development"
-  config.setup
 end
 
 Spec.after_each do

src/kemal/config.cr

@@ -7,6 +7,9 @@ module Kemal
   class Config
     INSTANCE           = Config.new
     HANDLERS           = [] of HTTP::Handler
+    CUSTOM_HANDLERS    = [] of Tuple(Nil | Int32, HTTP::Handler)
+    WEBSOCKET_HANDLERS = [] of HTTP::WebSocketHandler
+    FILTER_HANDLERS    = [] of HTTP::Handler
     ERROR_HANDLERS     = {} of Int32 => HTTP::Server::Context, Exception -> String
     {% if flag?(:without_openssl) %}
     @ssl : Bool?
@@ -31,10 +34,10 @@ module Kemal
       @always_rescue = true
       @server = uninitialized HTTP::Server
       @router_included = false
-      @custom_handler_position = 4
       @default_handlers_setup = false
       @running = false
       @shutdown_message = true
+      @handler_position = 0
     end
 
     def logger
@@ -51,9 +54,13 @@ module Kemal
 
     def clear
       @router_included = false
-      @custom_handler_position = 4
+      @handler_position = 0
       @default_handlers_setup = false
       HANDLERS.clear
+      CUSTOM_HANDLERS.clear
+      WEBSOCKET_HANDLERS.clear
+      FILTER_HANDLERS.clear
+      ERROR_HANDLERS.clear
     end
 
     def handlers
@@ -65,14 +72,20 @@ module Kemal
       HANDLERS.replace(handlers)
     end
 
-    def add_handler(handler : HTTP::Handler | HTTP::WebSocketHandler, position = Kemal.config.custom_handler_position)
+    def add_handler(handler : HTTP::Handler)
-      setup
+      CUSTOM_HANDLERS << {nil, handler}
-      HANDLERS.insert position, handler
+    end
-      @custom_handler_position = @custom_handler_position + 1
+
+    def add_handler(handler : HTTP::Handler, position : Int32)
+      CUSTOM_HANDLERS << {position, handler}
+    end
+
+    def add_handler(handler : HTTP::WebSocketHandler)
+      WEBSOCKET_HANDLERS << handler
     end
 
     def add_filter_handler(handler : HTTP::Handler)
-      HANDLERS.insert HANDLERS.size - 1, handler
+      FILTER_HANDLERS << handler
     end
 
     def error_handlers
@@ -92,6 +105,9 @@ module Kemal
         setup_log_handler
         setup_error_handler
         setup_static_file_handler
+        setup_custom_handlers
+        setup_filter_handlers
+        setup_websocket_handlers
         @default_handlers_setup = true
         @router_included = true
         HANDLERS.insert(HANDLERS.size, Kemal::RouteHandler::INSTANCE)
@@ -99,7 +115,8 @@ module Kemal
     end
 
     private def setup_init_handler
-      HANDLERS.insert(0, Kemal::InitHandler::INSTANCE)
+      HANDLERS.insert(@handler_position, Kemal::InitHandler::INSTANCE)
+      @handler_position += 1
     end
 
     private def setup_log_handler
@@ -108,18 +125,49 @@ module Kemal
                   else
                     Kemal::NullLogHandler.new
                   end
-      HANDLERS.insert(1, @logger.not_nil!)
+      HANDLERS.insert(@handler_position, @logger.not_nil!)
+      @handler_position += 1
     end
 
     private def setup_error_handler
       if @always_rescue
         @error_handler ||= Kemal::CommonExceptionHandler.new
-        HANDLERS.insert(2, @error_handler.not_nil!)
+        HANDLERS.insert(@handler_position, @error_handler.not_nil!)
+        @handler_position += 1
       end
     end
 
     private def setup_static_file_handler
-      HANDLERS.insert(3, Kemal::StaticFileHandler.new(@public_folder)) if @serve_static.is_a?(Hash)
+      if @serve_static.is_a?(Hash)
+        HANDLERS.insert(@handler_position, Kemal::StaticFileHandler.new(@public_folder))
+        @handler_position += 1
+      end
+    end
+
+    # Handle WebSocketHandler
+    private def setup_custom_handlers
+      CUSTOM_HANDLERS.each do |ch|
+        position = ch[0]
+        if !position
+          HANDLERS.insert(@handler_position, ch[1])
+          @handler_position += 1
+        else
+          HANDLERS.insert(position, ch[1])
+          @handler_position += 1
+        end
+      end
+    end
+
+    private def setup_websocket_handlers
+      WEBSOCKET_HANDLERS.each do |h|
+        HANDLERS.insert(@handler_position, h)
+      end
+    end
+
+    private def setup_filter_handlers
+      FILTER_HANDLERS.each do |h|
+        HANDLERS.insert(@handler_position, h)
+      end
     end
   end
 

src/kemal/helpers/helpers.cr

@@ -8,7 +8,11 @@
 # - Kemal::StaticFileHandler
 # - Here goes custom handlers
 # - Kemal::RouteHandler
-def add_handler(handler, position = Kemal.config.custom_handler_position)
+def add_handler(handler)
+  Kemal.config.add_handler handler
+end
+
+def add_handler(handler, position : Int32)
   Kemal.config.add_handler handler, position
 end
 

src/kemal/null_log_handler.cr

@@ -2,6 +2,7 @@ module Kemal
   # This is here to represent the logger corresponding to Null Object Pattern.
   class NullLogHandler < Kemal::BaseLogHandler
     def call(context)
+      puts "This is null"
       call_next(context)
     end