OpenRPC: user-attended RPC between sites

[Martin Atkins]

Taral wrote:
> On 7/16/05, Martin Atkins <mart at degeneration.co.uk> wrote:
> 
>>I've written some (very early, quick-and-dirty) words about OpenRPC here:
>>    <http://goathack.livejournal.org:9016/openrpc/>
>>
>>It describes roughly how the protocol in my demo works, and then goes on
>>to describe some of the things that I percieve to need more thought/work.
> 
> 
> This looks very useful. There seem to be too many communications back
> and forth, though. I envision:
> 
> 1. Client site causes user's browser to redirect to server site with
> RPC arguments, etc. Use a self-posting form if you need POST.
> 2. Server site asks user to approve request.
> 3a. If approved, site performs request and redirects back to client
> site with return value.
> 3b. If rejected, site redirects back to client site with exception value.
> 

The purpose of those extra requests is to avoid encoding
potentially-large requests and return values into a URL. Your idea of a
form sending the request with some JavaScript is an interesting one, but
requiring JavaScript would limit its use to fancy desktop browsers, and
the return values still need to go in the URL.

In the blog posting case the return values are small, but for profile
exchange the return value could potentially contain quite a lot of
information, since sites will want to request everything at once rather
than having the user click "Yes, I approve" repeatedly.