(*
 * Start this example in the `alice' interactive toplevel using
 *    use "HttpServerExample.aml";
 * then test it by
 * - creating a directory as given in `documentRoot', below;
 * - placing a file `foo.txt' in this directory;
 * - using a browser to navigate to
 *      http://localhost/foo.txt
 *)

import structure TextIO      from "x-alice:/lib/system/TextIO"
import structure Url         from "x-alice:/lib/system/Url"
import structure Http        from "x-alice:/lib/system/Http"
import structure HttpServer  from "x-alice:/lib/system/HttpServer"

val documentRoot = "/tmp/httproot"

val notFoundDocument = "The requested document could not be found\n"

fun documentHandler (request: Http.request) =
    let
	val relFile = Url.toString (Url.setQuery (#uri request, NONE))
	val file = TextIO.openIn (documentRoot ^ relFile)
	val body = TextIO.inputAll file
    in
	TextIO.closeIn file;
	Http.makeResponse
	    {statusCode = 200, contentType = "text/plain", body}
    end handle IO.Io {...} =>
	Http.makeResponse
	    {statusCode = 404, contentType = "text/plain",
	     body = notFoundDocument}

val port = HttpServer.start NONE
val _ = HttpServer.register (Url.empty, documentHandler)
val _ = TextIO.print ("started server at port " ^
		      Int.toString port ^ "\n")