Adapt StaticFileHandler for Crystal 1.6 (#3269)

src/ext/kemal_static_file_handler.cr

@@ -111,7 +111,7 @@ module Kemal
         if @fallthrough
           call_next(context)
         else
-          context.response.status_code = 405
+          context.response.status = HTTP::Status::METHOD_NOT_ALLOWED
           context.response.headers.add("Allow", "GET, HEAD")
         end
         return
@@ -124,7 +124,7 @@ module Kemal
       # File path cannot contains '\0' (NUL) because all filesystem I know
       # don't accept '\0' character as file name.
       if request_path.includes? '\0'
-        context.response.status_code = 400
+        context.response.status = HTTP::Status::BAD_REQUEST
         return
       end
 
@@ -143,13 +143,15 @@ module Kemal
         add_cache_headers(context.response.headers, last_modified)
 
         if cache_request?(context, last_modified)
-          context.response.status_code = 304
+          context.response.status = HTTP::Status::NOT_MODIFIED
           return
         end
 
         send_file(context, file_path, file[:data], file[:filestat])
       else
-        is_dir = Dir.exists? file_path
+        file_info = File.info?(file_path)
+        is_dir = file_info.try &.directory? || false
+        is_file = file_info.try &.file? || false
 
         if request_path != expanded_path
           redirect_to context, expanded_path
@@ -157,19 +159,21 @@ module Kemal
           redirect_to context, expanded_path + '/'
         end
 
-        if Dir.exists?(file_path)
+        return call_next(context) if file_info.nil?
+
+        if is_dir
           if config.is_a?(Hash) && config["dir_listing"] == true
             context.response.content_type = "text/html"
             directory_listing(context.response, request_path, file_path)
           else
             call_next(context)
           end
-        elsif File.exists?(file_path)
-          last_modified = modification_time(file_path)
+        elsif is_file
+          last_modified = file_info.modification_time
           add_cache_headers(context.response.headers, last_modified)
 
           if cache_request?(context, last_modified)
-            context.response.status_code = 304
+            context.response.status = HTTP::Status::NOT_MODIFIED
             return
           end
 
@@ -177,14 +181,12 @@ module Kemal
             data = Bytes.new(size)
             File.open(file_path, &.read(data))
 
-            filestat = File.info(file_path)
-
-            @cached_files[file_path] = {data: data, filestat: filestat}
-            send_file(context, file_path, data, filestat)
+            @cached_files[file_path] = {data: data, filestat: file_info}
+            send_file(context, file_path, data, file_info)
           else
             send_file(context, file_path)
           end
-        else
+        else # Not a normal file (FIFO/device/socket)
           call_next(context)
         end
       end