alice
library
manual.

The `HttpServer` structure

^Synopsis^{____________________________________________}

    signature HTTP_SERVER
    structure HttpServer : HTTP_SERVER

This structure provides a simple, extensible server for the HTTP/1.1 protocol as specified in RFC 2616.

See also: Url, Http, HttpClient, Socket

^Import^{______________________________________________}

    import structure HttpServer from "x-alice:/lib/system/HttpServer"
    import signature HTTP_SERVER from "x-alice:/lib/system/HTTP_SERVER-sig"

^Interface^{___________________________________________}

    signature HTTP_SERVER =
    sig
	type handler = Http.request -> Http.response

	val logOut : TextIO.outstream option ref
	val idleTime : Time.t ref

	val start : int option -> int
	val register : Url.t * handler -> unit
    end

^Description^{_________________________________________}

type handler = Http.request -> Http.response: The type of handlers for HTTP requests.
logOut: specifies a stream on which to write log messages about incoming connections and closed idle connections. The default is NONE.
idleTime: specifies the length of time to allow persistent connections to be idle before they are closed. The default is 30 seconds.
start portOpt: starts a HTTP server and lets it listen for connections in a concurrent thread. If portOpt is SOME port, tries to listen on port, else selects an available port. Returns the port on which it listens for request.
register (url, handler): registers handler for requests make to url. Only the path component or url is significant.

^Examples^{____________________________________________}

The following demonstrates how to start a simple HTTP server which interprets all requested URLs as files under a document root; it just returns the file with type text/plain. If the file could not be found, it returns a 404 Not Found response.

Download full source code

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")

last modified 2007/Mar/30 17:10

alice library manual.

The HttpServer structure

________ Synopsis ____________________________________________________

________ Import ______________________________________________________

________ Interface ___________________________________________________

________ Description _________________________________________________