[Seaside-dev] Re: encoded stream

[Lukas Renggli]

> I think Lukas actually ran into problems with this... Lukas?

Yes, I am totally frustrated. I have an image full of dirty packages
and everything is broken. ;-)

The problem is that WACodec is not suitable for streaming:

- WACodec works with Strings instead of Streams. So whenever you
convert something a copy is created.

- WACodec instances are singletons. They use a critical section to do
the conversion. I wonder why nobody has ever complained? Today when a
request/response is converted all other request handling is basically
suspended.

I suggest the following refactoring, but I need help because it
affects a lot of code:

- Change WACodec to a factory object for stream encoder/decoder.

- The WACodec class to be used is specific in the WAServerAdaptor.

- WANullCodec is the default codec to be used and the only one shipped
with Seaside-Core. It does nothing and provides the legacy WAKom
behavior.

- WACodec understands the methods #encoderFor:, #decoderFor:,
#urlEncoderFor:, #urlDecoderFor:, ... and wraps streams with platform
specific encoding strategies. Most platforms (with the exception of
Pharo) have highly efficient stream wrapper in their core library that
can be answered here.

- Platforms provide a limited set of useful subclasses of WACodec,
like WAUtf8NativeCodec, WAUtf8Utf8Codec, WAIsoUtf8Codec, etc. One
could also think of codexes that configure themselves using one of the
detection strategies in other web frameworks.

This kind of refactoring avoids unnecessary copying around and works
well with buffered and streamed request processing. The streamed
server currently includes an ugly hack and a lot of platform dependent
duplicated code to enable encoding.

What do you think?

Lukas

-- 
Lukas Renggli
http://www.lukas-renggli.ch