Hi Senaka,

I am confused here. I think you are taking the discussion to the
beginning. Because in the receiving side we read till the end of the
stream. Please see my first mail.

When sending writing part by part to the stream is same as chunking.
Because when sending either you should specify a content-length or
specified it as chunked.

-Manjula.

On Sat, 2008-03-15 at 13:39 +0530, Senaka Fernando wrote:
> >>>  BTW, this whole discussion is about in path, that is reading an
> >>>  incomming message. How about the out path? We have the same problems
> >>>  when sending attachments. Right now, we read the whole file into
> >>> memory
> >>>  and then only we send over the wire.
> >> hmm... Why not write it in chunks.. Read a chunk from the file, then
> >> write it to the outstream.. Use size of the file for content-type
> >> calculation in case of non-chunking.. But mostly people will use
> >> chunking when using MTOM..
> >
> > No, chunking is not required. You also don't need to write the entire data
> > to be sent, to the stream at once. Because any HTTP Receiver will pull
> > from the stream until it sees a valid ending character sequence.
> 
> It should rather read a length equal to content length. And the
> terminating sequence is for headers. Sorry for the confusion. Therefore,
> the HTTP Receiver will pull from the stream until it reads a content
> length or until an error occurs.
> 
> >
> > I believe that you should be able to write part by part to the stream, and
> > send it, then reuse the buffer and write part 2, and send and so on. This
> > argument can be justified, because on the receiving end, we must read the
> > multi-part data until we encounter the mime boundary, unlike an ordinary
> > payload where it can be terminated by a valid terminating character
> 
> Same here. We'll be reading a length equal to content length.
> 
> > sequence . We'll only have issues if we are to write large soap payloads
> > which of course can be dealt with once we've implemented Session in
> > Axis2/C.
> >
> > Regards,
> > Senaka
> >
> >>
> >> thanks,
> >> Thilina
> >>
> >>
> >>>
> >>>  Samisa...
> >>>
> >>>
> >>>
> >>>  > Regards,
> >>>  > Senaka
> >>>  >
> >>>  >
> >>>  >> Hi,
> >>>  >>
> >>>  >>>  > In Axis2/Java case we do write the attachment content directly
> >>> from
> >>>  >>>  > the InputStream to the File when the attachment size is larger
> >>> than
> >>>  >>>  > the threshold.  This avoids loading the whole attachment to the
> >>>  >>> memory
> >>>  >>>  > at all.
> >>>  >>>
> >>>  >>>  In this case to find out the attachment size don't you need to do
> >>> any
> >>>  >>>  mime parsing? How do you find the attachment size with out
> >>> searching
> >>>  >>> for
> >>>  >>>  the mime boundaries ?
> >>>  >>>
> >>>  >> Yes.. MIME is a boundary based packaging mechanism and you does not
> >>>  >> need to specify the length for each of the parts...Even the HTTP
> >>>  >> content length is not there if the message is chunked.
> >>>  >>
> >>>  >> What we did in Axis2/Java to overcome this is to read the data to a
> >>>  >> byte[] buffer of up to a certain size (the size threshold). If
> >>> there
> >>>  >> are more data available in the mime part (if we have not
> >>> encountered
> >>>  >> the boundary yet) then we know this attachment is bigger than the
> >>>  >> threshold. So we create the temp file, pump the content in the
> >>> buffer
> >>>  >> to the file, then pump the rest of the stream to the file.. In this
> >>>  >> way we do not need to know the size of the attachment upfront.. BTW
> >>> we
> >>>  >> do all of the above while we are parsing the MIME message at the
> >>> MIME
> >>>  >> parser level..
> >>>  >>
> >>>  >>
> >>>  >>>  > This has the plus point that the attachment size will be
> >>>  >>>  > limited only by the available free space in the Temp
> >>> Directory..
> >>>  >>>  > Will that be possible in Axis2/C.. Or is that wat you have in
> >>> mind
> >>>  >>> :)..
> >>>  >>>
> >>>  >>>  Yes this is possible.
> >>>  >>>
> >>>  >> But in Axis2/JAVA we will get a OutOfMemory if we parse a large
> >>> MIME
> >>>  >> part upfront, since it reads the attachment to memory. May be you
> >>> can
> >>>  >> have a larger limit with C than in Java, but ultimately you'll come
> >>> to
> >>>  >> a situation where you will not have enough memory to store that
> >>> MIME
> >>>  >> part in memory in the parsing time, unless you write in to a File
> >>>  >> while parsing,..
> >>>  >>
> >>>  >> thanks,
> >>>  >> Thilina
> >>>  >>
> >>>  >>
> >>>  >>>
> >>>  >>>  >
> >>>  >>>  > thanks,
> >>>  >>>  > Thilina
> >>>  >>>  >
> >>>  >>>  >  >and keeping the file name inside
> >>>  >>>  > >  data_handler instead of the whole buffer. So the service or
> >>> the
> >>>  >>> client
> >>>  >>>  > >  will get the file name instead of the buffered stream, when
> >>> it
> >>>  >>> receives
> >>>  >>>  > >  an attachment. This will not prevent buffering the
> >>> attachment
> >>> at
> >>>  >>> the
> >>>  >>>  > >  transport but will prevent keeping it inside the om_tree
> >>> till
> >>> it
> >>>  >>> reaches
> >>>  >>>  > >  the receiver.
> >>>  >>>  > >
> >>>  >>>  > >  Before implementing this I would like to know your
> >>> suggestions
> >>>  >>> regarding
> >>>  >>>  > >  this.
> >>>  >>>  > >
> >>>  >>>  > >  [1] https://issues.apache.org/jira/browse/AXIS2C-672
> >>>  >>>  > >
> >>>  >>>  > >  Thanks,
> >>>  >>>  > >  -Manjula
> >>>  >>>  > >
> >>>  >>>  > >  --
> >>>  >>>  > >  Manjula Peiris: http://manjula-peiris.blogspot.com/
> >>>  >>>  > >
> >>>  >>>  > >
> >>>  >>>  > >  
> >>> ---------------------------------------------------------------------
> >>>  >>>  > >  To unsubscribe, e-mail: [EMAIL PROTECTED]
> >>>  >>>  > >  For additional commands, e-mail:
> >>> [EMAIL PROTECTED]
> >>>  >>>  > >
> >>>  >>>  > >
> >>>  >>>  >
> >>>  >>>  >
> >>>  >>>  >
> >>>  >>>
> >>>  >>>
> >>>  >>>  
> >>> ---------------------------------------------------------------------
> >>>  >>>  To unsubscribe, e-mail: [EMAIL PROTECTED]
> >>>  >>>  For additional commands, e-mail: [EMAIL PROTECTED]
> >>>  >>>
> >>>  >>>
> >>>  >>>
> >>>  >>
> >>>  >> --
> >>>  >> Thilina Gunarathne - http://thilinag.blogspot.com
> >>>  >>
> >>>  >> ---------------------------------------------------------------------
> >>>  >> To unsubscribe, e-mail: [EMAIL PROTECTED]
> >>>  >> For additional commands, e-mail: [EMAIL PROTECTED]
> >>>  >>
> >>>  >>
> >>>  >>
> >>>  >
> >>>  >
> >>>  > ---------------------------------------------------------------------
> >>>  > To unsubscribe, e-mail: [EMAIL PROTECTED]
> >>>  > For additional commands, e-mail: [EMAIL PROTECTED]
> >>>  >
> >>>  >
> >>>  >
> >>>  >
> >>>
> >>>
> >>>  --
> >>>  Samisa Abeysinghe
> >>>  Software Architect; WSO2 Inc.
> >>>
> >>>  http://www.wso2.com/ - "Oxygenating the Web Service Platform."
> >>>
> >>>
> >>>
> >>>
> >>>  ---------------------------------------------------------------------
> >>>  To unsubscribe, e-mail: [EMAIL PROTECTED]
> >>>  For additional commands, e-mail: [EMAIL PROTECTED]
> >>>
> >>>
> >>
> >>
> >>
> >> --
> >> Thilina Gunarathne - http://thilinag.blogspot.com
> >>
> >> ---------------------------------------------------------------------
> >> To unsubscribe, e-mail: [EMAIL PROTECTED]
> >> For additional commands, e-mail: [EMAIL PROTECTED]
> >>
> >>
> >
> >
> > ---------------------------------------------------------------------
> > To unsubscribe, e-mail: [EMAIL PROTECTED]
> > For additional commands, e-mail: [EMAIL PROTECTED]
> >
> >
> 
> 
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: [EMAIL PROTECTED]
> For additional commands, e-mail: [EMAIL PROTECTED]
> 


---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]

Reply via email to