Allow config.server to be lazily initiliazed. Fixes #396

src/kemal.cr

@@ -32,11 +32,6 @@ module Kemal
     config.setup
     config.port = port if port
 
-    config.server = HTTP::Server.new(config.host_binding, config.port, config.handlers)
-    {% if !flag?(:without_openssl) %}
-    config.server.tls = config.ssl
-    {% end %}
-
     unless Kemal.config.error_handlers.has_key?(404)
       error 404 do |env|
         render_404
@@ -63,15 +58,21 @@ module Kemal
       end
     end
 
+    server = HTTP::Server.new(config.host_binding, config.port, config.handlers)
+    {% if !flag?(:without_openssl) %}
+    server.tls = config.ssl
+    {% end %}
+    config.server ||= server
     config.running = true
+
     yield config
-    config.server.listen if config.env != "test"
+    config.server.not_nil!.listen if config.env != "test" && config.server
   end
 
   def self.stop
     if config.running
       if config.server
-        config.server.close
+        config.server.not_nil!.close
         config.running = false
       else
         raise "Kemal.config.server is not set. Please use Kemal.run to set the server."

src/kemal/config.cr

@@ -20,7 +20,7 @@ module Kemal
 
     getter custom_handler_position
     property host_binding, ssl, port, env, public_folder, logging, running
-    property always_rescue, server, extra_options, shutdown_message
+    property always_rescue, server : HTTP::Server?, extra_options, shutdown_message
     property serve_static : (Bool | Hash(String, Bool))
     property static_headers : (HTTP::Server::Response, String, File::Stat -> Void)?
 
@@ -34,7 +34,6 @@ module Kemal
       @logger = nil
       @error_handler = nil
       @always_rescue = true
-      @server = uninitialized HTTP::Server
       @router_included = false
       @default_handlers_setup = false
       @running = false