1 files changed, 15 insertions, 4 deletions
diff --git a/actionpack/lib/action_dispatch/middleware/params_parser.rb b/actionpack/lib/action_dispatch/middleware/params_parser.rb
index e65279a285..9cde9c9b98 100644
--- a/actionpack/lib/action_dispatch/middleware/params_parser.rb
+++ b/actionpack/lib/action_dispatch/middleware/params_parser.rb
@@ -1,9 +1,14 @@
-require 'active_support/core_ext/hash/conversions'
 require 'action_dispatch/http/request'
-require 'active_support/core_ext/hash/indifferent_access'
 
 module ActionDispatch
+  # ActionDispatch::ParamsParser works for all the requests having any Content-Length
+  # (like POST). It takes raw data from the request and puts it through the parser
+  # that is picked based on Content-Type header.
+  #
+  # In case of any error while parsing data ParamsParser::ParseError is raised.
   class ParamsParser
+    # Raised when raw data from the request cannot be parsed by the parser
+    # defined for request's content mime type.
     class ParseError < StandardError
       attr_reader :original_exception
 
@@ -21,6 +26,10 @@ module ActionDispatch
       }
     }
 
+    # Create a new +ParamsParser+ middleware instance.
+    #
+    # The +parsers+ argument can take Hash of parsers where key is identifying
+    # content mime type, and value is a lambda that is going to process data.
     def initialize(app, parsers = {})
       @app, @parsers = app, DEFAULT_PARSERS.merge(parsers)
     end
@@ -28,7 +37,9 @@ module ActionDispatch
     def call(env)
       request = Request.new(env)
 
-      request.request_parameters = parse_formatted_parameters(request, @parsers)
+      parse_formatted_parameters(request, @parsers) do |params|
+        request.request_parameters = params
+      end
 
       @app.call(env)
     end
@@ -39,7 +50,7 @@ module ActionDispatch
 
         strategy = parsers.fetch(request.content_mime_type) { return nil }
 
-        strategy.call(request.raw_post)
+        yield strategy.call(request.raw_post)
 
       rescue => e # JSON or Ruby code block errors
         logger(request).debug "Error occurred while parsing request parameters.\nContents:\n\n#{request.raw_post}"