https://gist.github.com/2834137 Slightly modified to be compatible cowboy 0.6

uploader.erl

%%%-------------------------------------------------------------------
%%% @author egobrain <egobrain@linux-ympb>
%%% @copyright (C) 2012, egobrain
%%% @doc
%%%  Function for uploading files and properties,which were sent as a
%%%  multipart. Files are stored in tmp_folder with random name,
%%%  generated by tmp_filename function.
%%% @end
%%% Created : 25 Mar 2012 by egobrain <egobrain@linux-ympb>
%%%-------------------------------------------------------------------
-module(uploader).

-export([files_qs/1,
   files_qs/2]).

-define(MAX_FILE_SIZE, 5000000).
-define(MAX_FILES, unlimited).
-define(TMP_PATH, "/tmp").
-define(TMP_FILE_NAME, fun tmp_filename/1).

-record(state,{
	  headers = [],
	  max_file_size = ?MAX_FILE_SIZE :: non_neg_integer(),
	  max_files = ?MAX_FILES :: non_neg_integer() | unlimited,
	  tmp_folder = ?TMP_PATH :: string(),
	  tmp_filename = ?TMP_FILE_NAME :: function(),
	  files_cnt = 0
	 }).

-record(datafile,{name = <<"">> :: binary(),
		  size = 0 :: non_neg_integer(),
		  'Content-Type' :: binary(),
		  'Original-Name' :: binary()
		 }).

%% ===================================================================
%%% Types
%% ===================================================================

-type datafile() :: #datafile{}.
-type headers() :: [datafile() | {cowboy_http:header(), iodata()}].

-type option() :: {max_file_size, Size :: non_neg_integer()} |
                  {tmp_filename,Fun :: function()} |
                  {tmp_folder, Path :: string}.

-type options() :: [option()].

-type error() :: {error, file_too_big | max_files_limit}.

-export_type([datafile/0,headers/0,options/0]).

%% ===================================================================
%%% Api
%% ===================================================================

-spec files_qs(Req :: cowboy_http:req()) -> {headers(), Req  :: cowboy_http:req() } | error().
files_qs(Req) ->
    files_qs(Req, []).

-spec files_qs(Req  :: cowboy_http:req() , Options :: options()) -> {headers(), Req :: cowboy_http:req()} | error().
files_qs(Req, Options) ->
    State = #state{headers=[],
		   files_cnt=0,
		   max_file_size= proplists:get_value(max_file_size,Options, ?MAX_FILE_SIZE),
		   max_files    = proplists:get_value(max_files,    Options, ?MAX_FILES),
		   tmp_folder   = proplists:get_value(tmp_folder,   Options, ?TMP_PATH),
		   tmp_filename = proplists:get_value(tmp_filename, Options, ?TMP_FILE_NAME)
		  },
    acc(Req, State).

%% ===================================================================
%%% Internal functions
%% ===================================================================

acc(Req,State) ->
    case cowboy_req:multipart_data(Req) of
      {headers, Headers, Req2} ->
        acc({headers, Headers}, Req2, State);
      {eof, Req2} ->
        acc(eof, Req2, State)
    end.

acc({headers,NewHeaders},Req,#state{headers=Headers,
				    tmp_folder=TmpFolder,
				    tmp_filename=TmpFilenameFun,
				    max_file_size=MaxFileSize,
				    max_files=MaxFiles,
				    files_cnt=FilesCnt
				   } = State) ->
  case parse_headers(NewHeaders) of
    {error,_Reason} = Err ->
      Err;
    {Name, undefined} ->
	    {Value,Req2} = acc_property(Req),
	    acc(Req2,State#state{headers=[{Name,Value}|Headers]});
    {Name, Filename} ->
	    case MaxFiles =:= unlimited orelse FilesCnt < MaxFiles of
        true ->
          TempFilename = filename:join([TmpFolder,TmpFilenameFun(Filename)]),
          {ok, File} = file:open(TempFilename, [raw, write]),
          Res = acc_file(Req,File,MaxFileSize),
          file:close(File),
          case Res of
            {error,file_too_big} = Err ->
              file:delete(TempFilename),
              delete_files(Headers),
              Err;
            {FileSize,Req2} ->
              FileProp = #datafile{name=TempFilename,
                size=FileSize,
                'Original-Name'=Filename,
                'Content-Type'=
                  proplists:get_value('Content-Type',NewHeaders)},
%% Mana shuni tugrilashimiz kerak
              acc(Req2,State#state{headers=[FileProp,Headers],files_cnt=FilesCnt+1})
          end;
        false ->
          delete_files(Headers),
          {error,max_files_limit}
      end
    end;	

acc(eof,Req,#state{headers=Headers})  -> {Headers,Req}.


parse_headers(Headers) ->
    case proplists:get_value(<<"content-disposition">>,Headers) of
	undefined ->
	    {error,"No content disposition in header"};
	Value ->
	    {_FormData,Props} = cowboy_multipart:content_disposition(Value),
	    Name = proplists:get_value(<<"name">>,Props),
	    Filename = proplists:get_value(<<"filename">>,Props),
	    {Name,Filename}
    end.


-spec acc_file(Req  :: cowboy_http:req() , File :: file:io_device() ,MaxFileSize :: non_neg_integer()) ->
    {FileSize :: non_neg_integer(), Req2  :: cowboy_http:req()} |
	{error,file_too_big}.
acc_file(Req,File,MaxFileSize) -> acc_file(Req,File,0,MaxFileSize).
acc_file(Req,File,FileSize,MaxFileSize) ->
  case cowboy_req:multipart_data(Req) of
    {end_of_part, Req2} ->
      {FileSize,Req2};
    {body,Data, Req2} ->
	    NewFileSize = FileSize + byte_size(Data),
	    case NewFileSize > MaxFileSize of
        true ->
          {error,file_too_big};
        false ->
          ok = file:write(File,Data),
		    acc_file(Req2,File,NewFileSize,MaxFileSize)
	    end
    end.
	    
-spec acc_property(_Req) -> {Data :: binary(),_Req2}.    
acc_property(Req) ->
    acc_property(Req,<<>>).

acc_property(Req,Buff) ->
  case cowboy_req:multipart_data(Req) of
    {end_of_part, Req2} ->
      {Buff, Req2};
    {body,Data, Req2} ->
      acc_property(Req2,<<Buff/binary,Data/binary>>)
    end.

%% ===================================================================
%%% Default Functions
%% ===================================================================

-spec tmp_filename(OriginalName :: binary()) -> string() | [string()].
tmp_filename(_OriginalName) ->
    atom_to_list(?MODULE) ++ integer_to_list(erlang:phash2(make_ref())).

delete_files(Headers) ->
    lists:foreach(fun(#datafile{name=FName}) ->
			  file:delete(FName);
		     (_) -> ok
		  end,Headers).

Thanks, that's great!!!

Please, tell me!
How set more timeout wait data upload?
Вecause that, i think, when i test uploading file on my Android app client i have error, please see this Request logs:

{http_req,#Port<0.2049>,ranch_tcp,keepalive,<0.301.0>,
                             <<"POST">>,'HTTP/1.1',
                             {{95,136,120,140},49970},
                             <<"194.8.153.60">>,undefined,8010,<<"/upload/">>,
                             undefined,<<>>,undefined,[],
                             [{<<"content-length">>,<<"1604016">>},
                              {<<"content-type">>,
                               <<"multipart/form-data; boundary=vu7qfgk_fb4fJJkk129W4fm76ACngk9Thpm">>},
                              {<<"host">>,<<"194.8.153.6:8010">>},
                              {<<"connection">>,<<"Keep-Alive">>}],
                             [{<<"connection">>,[<<"keep-alive">>]}],
                             undefined,[],waiting,undefined,
                             <<"--vu7qfgk_fb4fJJkk129W4fm76ACngk9Thpm\r\nContent-Disposition: form-data; name=\"\";
 filename=\"1.mp4\"\r\nContent-Type: application/octet-stream\r\nContent-Transfer-Encoding: binary\r\n\r\n">>,
                             false,waiting,[],<<>>,undefined}

ERROR logs:

ERROR REPORT==== 31-Jul-2013::19:37:24 ===
** Cowboy handler cdn_post_file terminating in handle/2
   for the reason error:{case_clause,{error,timeout}}
** Handler state was undefined
** Request was [{socket,#Port<0.2049>},
                {transport,ranch_tcp},
                {connection,keepalive},
                {pid,<0.301.0>},
                {method,<<"POST">>},
                {version,'HTTP/1.1'},
                {peer,{{95,136,120,140},49970}},
                {host,<<"194.8.153.60">>},
                {host_info,undefined},
                {port,8010},
                {path,<<"/upload/">>},
                {path_info,undefined},
                {qs,<<>>},
                {qs_vals,undefined},
                {bindings,[]},
                {headers,[{<<"content-length">>,<<"1604016">>},
                          {<<"content-type">>,
                           <<"multipart/form-data; boundary=vu7qfgk_fb4fJJkk129W4fm76ACngk9Thpm">>},
                          {<<"host">>,<<"194.8.153.60:8010">>},
                          {<<"connection">>,<<"Keep-Alive">>}]},
                {p_headers,[{<<"connection">>,[<<"keep-alive">>]}]},
                {cookies,undefined},
                {meta,[]},
                {body_state,waiting},
                {multipart,undefined},
                {buffer,<<"--vu7qfgk_fb4fJJkk129W4fm76ACngk9Thpm\r\nContent-Disposition: form-data; name=\"\";
 filename=\"1.mp4\"\r\nContent-Type: application/octet-stream\r\nContent-Transfer-Encoding: binary\r\n\r\n">>},
                {resp_compress,false},
                {resp_state,waiting},
                {resp_headers,[]},
                {resp_body,<<>>},
                {onresponse,undefined}]
** Stacktrace: [{cowboy_req,multipart_data,3,
                            [{file,"src/cowboy_req.erl"},{line,825}]},
                {cdn_file_uploader,acc_file,4,
                                   [{file,"src/cdn_file_uploader.erl"},
                                    {line,141}]},
                {cdn_file_uploader,acc,3,
                                   [{file,"src/cdn_file_uploader.erl"},
                                    {line,99}]},
                {cdn_post_file,handle_upload,2,
                               [{file,"src/cdn_post_file.erl"},{line,44}]},
                {cowboy_handler,handler_handle,4,
                                [{file,"src/cowboy_handler.erl"},{line,119}]},
                {cowboy_protocol,execute,4,
                                 [{file,"src/cowboy_protocol.erl"},
                                  {line,523}]}]

Thank You very much!!!

Thank you!
I realized!!! My Android Client send file on server very slow-slow, and need more timeout, but also for local network ( 5MB filesize = 60 s) i m set time out 100000, its badly (

Sorry, I just saw your comments. Somehow, github failed to notify me about them.

@buriwoy Thanks for your gist!
it work fine.
But tell me please, how can I get parameters from multipart form POST request, when I upload the file with the?
Web form have "User name", "Comment", and othere sending parameters

@buriwoy
Thank you for giving me time to think and understand
I myself was able to get an answer to my question:

{Opts, Req2} = file_uploader:files_qs(Req),
{_, Comment} = lists:keyfind(<<"comment">>,1, lists:flatten(Opts)),