Re: [Haskell-cafe] JavaScript in a browser as a Windows GUI?

On Thu, Oct 21, 2010 at 8:00 PM, Jeremy Shaw wrote:

On Thu, Oct 21, 2010 at 12:04 PM, Andrew Coppin wrote:

...

My understanding is that Happstack is a very large, powerful and complex framework for writing Haskell web applications. I was under the impression that you use it by statically linking the HTTP server and the actual application together, rather than Happstack providing a standard CGI interface that an external application can then use.

powerful - yes! large and complex -- not so much. Though, the lower bound on complexity is limited by the fundamental complexity of the web itself.

But, you are correct that happstack does not currently have support for running CGI executables. I imagine that you could write a CGI handler (with out modifying the core code) in a few hours (maybe less). Mostly just a matter of turning the values in the Request type into a environment variables, and calling the executable?

That said, I am not sure why you want CGI. CGI is only simple in the sense that it doesn't do anything for you. But that means you have to handle all the complexity yourself. Perhaps it would be easier to just learn happstack. It is much better documented now than it was a few years ago (and some aspects have been simplified). And happstack-state and happstack-server are now completely independent.

Here is a nice tutorial, http://happstack.com/docs/crashcourse/index.html The darcs version (which will be released soon) has much better haddock documentation as well. I would recommend the darcs version for any new development.

Shouldn't it be possible to plug in the happstack-wai experimental port with Network.Wai.Handler.CGI and then both get the power of Happstack *and* easy CGI support? And then later on, when ready to move past CGI it will be easy to move to a better deployment option. Michael