[Lazarus] fpWeb file download

[ABorka]

On 6/10/2010 13:30, Leonardo M. Ramé wrote:
> El jue, 10-06-2010 a las 17:23 -0300, Leonardo M. Ramé escribió:
>> Hi, I'm trying to implement file downloading for an fpWeb CGI without
>> success, I'm doing this so far:
>>
>> procedure TFPWebModule1.TFPWebActions0Request(Sender: TObject;
>>    ARequest: TRequest; AResponse: TResponse; var Handled: Boolean);
>> var
>>    lImage: string;
>>    lFileStream: TFileStream;
>> begin
>>      lImage := '/home/leonardo/files/file1.dcm';
>>      lFileStream := TFileStream.Create(lImage, fmShareDenyNone);
>>      try
>>        AResponse.ContentType := 'image/dicom3';
>>        AResponse.CustomHeaders.Values['Content-Disposition'] :=
>>          'attachment; filename=' + ExtractFileName(lImage);
>>        AResponse.LoadFromStream(lFileStream, True);
>>        AResponse.SendContent; // not sure if this is needed.
>>      finally
>>        lFileStream.Free;
>>      end;
>>    Handled := True;
>> end;
>>
>> And the results of curl are this:
>>
>> * About to connect() to localhost port 80 (#0)
>> *   Trying ::1... connected
>> * Connected to localhost (::1) port 80 (#0)
>>> GET /cgi-bin/getstudy/StudyId?IdSeries=1 HTTP/1.1
>>> User-Agent: curl/7.19.7 (x86_64-pc-linux-gnu) libcurl/7.19.7
>> OpenSSL/0.9.8k zlib/1.2.3.3 libidn/1.15
>>> Host: localhost
>>> Accept: */*
>>>
>> <  HTTP/1.1 200 OK
>> <  Date: Thu, 10 Jun 2010 20:17:52 GMT
>> <  Server: Apache/2.2.14 (Ubuntu)
>> <  Content-Disposition: attachment; filename=MR_4c1139a4b76d62c2.dcm
>> <  Content-Length: 0
>> <  Content-Type: image/dicom3
>> <
>> * Connection #0 to host localhost left intact
>> * Closing connection #0
>>
>> As you can see, the Content-Lenght is 0, and the image isn't downloaded.
>> What is the correct way of implementing this?.
>>
>
> Sorry, I found the solution (I just needed to create an instance of
> AResponse.ContentStream):
>
> AResponse.ContentStream :=  TFileStream.Create(lImage, fmShareDenyNone);
> try
>    AResponse.ContentType := 'image/dicom3';
>    AResponse.CustomHeaders.Values['Content-Disposition'] := 'attachment;
> filename=' + ExtractFileName(lImage);
>    AResponse.ContentLength := AResponse.ContentStream.Size;
>    AResponse.SendContent;
> finally
>     AResponse.ContentStream.Free;
> end;

The filename might need to be between double quotes, like
AResponse.CustomHeaders.Add('Content-Disposition= attachment; 
filename="blah blah.csv"');

because there might be some spaces in the name for example.

Also, I am not sure but does the AResponse.ContentStream need to be 
freed after the SendContent or SendResponse? If I remember right, back 
it old delphi days with the proper way, the stream was not freed. Not 
sure how it works in FPC/Lazarus though.

AB