D web apps: cgi.d now supports scgi

[Adam D. Ruppe]

https://github.com/adamdruppe/misc-stuff-including-D-programming-language-web-stuff

some docs:
http://arsdnet.net/web.d/cgi.html
http://arsdnet.net/web.d/cgi.d.html

The file cgi.d in there is my base library for web apps.

Previously, it spoke regular CGI, FastCGI (with help
from a C lib) and HTTP (with help from the netman.d
and httpd.d files in that github).


Now, in addition to those options, it also speaks
SCGI - all by itself - and it can speak http without
needing helper modules.

The new embedded http server should work on all
platforms too, not just linux like the old one, but
I haven't tested it yet.


This finishes out all the major web app interfaces
that I'm aware of.


To use them, you write your app with a GenericMain
and always communicate through the Cgi object it
passes you.

===
import arsd.cgi;
void hello(Cgi cgi) {
     cgi.write("Hello, world! " ~ cgi.request("name") ~ "\n");
}
mixin GenericMain!hello;
===


And then compile:

dmd hello.d arsd/cgi.d # builds a CGI binary
dmd hello.d arsd/cgi.d -version=fastcgi # FastCGI. needs libfcgi 
C lib
dmd hello.d arsd/cgi.d -version=scgi # SCGI
dmd hello.d arsd/cgi.d -version=embedded_httpd # built-in http 
server


The API is the same with all four options.

With cgi or fastcgi, you put the binary where your web
server can run it.

With scgi and embedded_httpd, you run the binary. It
persists as an application server. On the command line,
you can say use the option "--port 5000" for example
to change the listening tcp port.

The default for httpd right now is 8085. The default
for scgi is 4000.



Well, I don't have much else to say, but since it
now does all four of the big interfaces easily,
I thought I'd say something here.

If you're interested in web programming with D,
this will lay the foundation for you.