lennykean
Make ReadAsMultipartAsync lazy
this looks like a great start. I've had a look at the code behind the ReadAsMultipartAsync method and it has one really big flaw. It reads the entire contents into memory. The typical usage I've seen with the MTOM encoder has been when needing to transfer large amounts of data over a SOAP service. Normally SOAP will encode a byte[] as base64 encoded string which increases it's size by ~30%. This is a lot when transferring 200MB of data. MTOM doesn't really gain you much unless you are sending large amounts of data. It might be possible to use the building blocks in the Microsoft.AspNet.WebApi.Client package to build something better. Basically an implementation of ReadAsMultipartAsync needs to lazily create each of the contained HttpContent objects. The HttpContent parts also need to return a stream from ReadAsStreamAsync which isn't backed by an in memory buffer but read from the actual network stream and fake an EOF once the part has been completely read. What you've provided is great if you aren't returning a large amount of data, and the limitations are mainly in the Microsoft.AspNet.WebApi.Client code. Edit: I just asked a colleague on the ASP.NET Core team if there was a nicer implementation and he pointed me to this. You can see some sample usage here. It looks like it wouldn't take a lot of work to switch to using that implementation which solves these problems.
