使用kbmmw 的REST 服务实现上传大文件

 [kbmMW_Rest(‘method:post, path:uploadfile,anonymousResult:False,freeResult:true‘)]
      [kbmMW_Method]
      function uploadfile(

          [kbmMW_Rest(‘value: "$filepath", required: true‘)] const filepath:string;

          [kbmMW_Rest(‘value: "$token", required: true‘)] const token:string;

          [kbmMW_Rest(‘value: "$position", required: true‘)] const position:string;

          [kbmMW_Rest(‘value: "$size", required: true‘)] const size:string;

          [kbmMW_Rest(‘value: "$final", required: true‘)] const  final:string):string;

function TkbmMWCustomHTTPSmartService1.uploadfile(const filepath, token,
  position, size, final: string): string;
const
   UPLOADPATH=‘d:\upload\‘;
   MaxFileSize=200*1024*1024; //上传文件大小不能超过200M
   errmsg=‘ERROR:‘;
var
   fa:TkbmMWFileAccessPermissions;
   h:THandle;
   FileToken:integer;
   path:string;
   p:Pbyte;
  // l:integer;
   ref:TkbmMWFileReference;
   fofs,sz,newofs,maxsize:int64;
   bGC:boolean;
   FFinal:boolean;
begin
   if not Assigned(FilePool) then
      begin
        result:=errmsg+‘No FilePool defined.‘;
        exit;
      end;

   if filepath=‘‘ then
    begin
        result:=errmsg+‘No filepath.‘;
        exit;
      end;
   if token=‘‘ then
       begin
        result:=errmsg+‘No token.‘;
        exit;
      end;

   if position=‘‘ then
       begin
        result:=errmsg+‘No position.‘;
        exit;
      end;

    fofs:=strtoint(position);


    if size=‘‘ then
    begin
        result:=errmsg+‘No size.‘;
        exit;
      end;

   sz:=strtoint(size);

  if sz>10*1024*1024 then
     begin
         result:=errmsg+‘blocksize too big.‘;
        exit;
     end;

    if ((final<>‘0‘) and (final<>‘1‘)) then
    begin
        result:=errmsg+‘final error.‘;
        exit;
    end;

  if final=‘0‘ then
    ffinal:=False
   else
   ffinal:=True;

     FileToken:=strtoint(token);

     path:= UPLOADPATH+filepath;
    // Determine file mode.
     if FileToken=-1 then
     begin
          // Check if file already exists and not overwrite permissions.
          if FileExists(path) and (not (mwfapOverwrite in fa)) then
           begin
             result:=errmsg+‘Permission denied‘;
             exit;
           end;
     end;

      // Append block to file.
     bGC:=false;
     ref:=FilePool.Access(path,mwfamOpenWrite,FileToken,h);
     try
        ref.DuringUpdate:=true;

        maxsize:=MaxFileSize;
        if FOfs>=0 then
        begin
             if (maxsize>0) and (FOfs+sz>maxSize) then
              begin
                result:=errmsg+‘File too big‘;
                exit;
              end;

             if FileSeek(h,FOfs,0)<0 then
             begin
                result:=errmsg+‘Cant position in file‘;
                exit;


             end;
        end
        else
        begin
             newofs:=FileSeek(h,0,2);
             if newofs<0 then
              begin
                result:=errmsg+‘Cant append to file‘;
                exit;
              end;

             if (maxsize>0) and (newofs+sz>maxSize) then
              begin
                result:=errmsg+‘File too big‘;
                exit;
              end;
        end;

        // Write requeststream to file.
        p:=RequestStream.Memory;
        if FileWrite(h,p^,sz)<>sz then
        begin
             ref.Invalidate;
            
                ref.DeleteOnGC:=true;
             bGC:=true;
         
            result:=errmsg+‘写文件失败.‘;
           exit;
        end;
     finally
       if FFinal then
          ref.DuringUpdate:=false;
        FilePool.ReleaseAccess(ref,h,FFinal);
        if bGC then
           FilePool.GarbageCollect;
     end;
     Result:=FileToken.ToString ;

end;

procedure TForm1.Button3Click(Sender: TObject);
const
 FBlockSize=2*1024*1024;

 baseurl=‘http://127.0.0.1/xalionrest‘;
 basepath=‘d:\‘;
var
  HttpClient:TNetHTTPClient;
  requrl:string;
  filetoken:string;
  resp:IHTTPResponse;
  final:string;
  terminate:boolean;
  Stream:TFileStream;
  fm:integer;
  position,sz:string;
  pct:integer;
  RequestStream:Tmemorystream;
  LocalPath,filename:string;
  n,bs,ofs:integer;

begin

   filename:= ‘delphi5.rar‘;
   localpath:=basepath+filename;


  fm:=fmOpenRead+fmShareDenyWrite;
  Stream:=TFileStream.Create(LocalPath,fm);

  HttpClient:= TNetHTTPClient.create(nil);

  RequestStream:= Tmemorystream.Create;

  filetoken:=‘-1‘;
  final:=‘0‘;
 try
  while true do
        begin
             if Stream.Size=0 then
                pct:=100
             else
                 pct:=trunc((Stream.Position / Stream.Size) * 100);
             
            

             position:=Stream.Position.ToString;
             sz:=Stream.Size.ToString;

             RequestStream.Clear;
             n:=FBlockSize;
             ofs:=Stream.Position;
             bs:=Stream.Size-ofs;
             if bs<=0 then break;
             if bs<=n then
             begin
                  n:=bs;
                  final:=‘1‘;
             end;
             RequestStream.CopyFrom(Stream,n);
   
             RequestStream.Position:=0;
                  try

                     requrl:= baseurl+‘/uploadfile?‘+‘filepath=‘+filename+‘&token=‘+filetoken+‘&position=‘+position+‘&size=‘+n.ToString+‘&final=‘+final;
                     resp:=httpclient.Post(requrl,RequestStream);//
                     filetoken:=resp.ContentAsString();

                     if pos(‘ERROR:‘,filetoken)>0 then
                       begin
                         showmessage(filetoken);
                         exit;

                       end;


                    
                  except
                      showmessage(‘上传失败！‘);
                      exit;
                   end;
        
             if n<FBlockSize then
                break;

             
        end;

   showmessage(‘上传成功！‘);
    
     finally
      

        Stream.Free;

         HttpClient.Free;

        RequestStream.free;
     end;


end;