appjet-app-base/lib-app/dispatch-plus.js

/* appjet:version 0.1 */
/* appjet:library */
// Copyright (c) 2009, Herbert Vojčík
// Licensed by MIT license (http://www.opensource.org/licenses/mit-license.php)

/** Decoded segments of full path */
request.fullPathSegments = request.path.split('/').map(decodeURIComponent);
/** Decoded full path */
request.fullPath = request.fullPathSegments.join('/');

/**@ignore*/
request.fullPathSegments.of = request.fullPath;

/**
  * <p>Enhanced dispatcher function. Dispatches according to request.fullPath. Allows for:</p>
  * <ul><li>nonalphanumeric characters in path. Serve /robots.txt with <code>get_robots$txt</code></li>
  * <li>subpath matching: <ul>
  *   <li>Serve /foo/, /foo/bar and /foo/bar/baz from <code>get_foo_</code></li>
  *   <li><code>get_foo_main</code> serves only the /foo/ path, but not the /foo/bar, nor /foo</li>
  *   <li>If there are more functions matching, the most specific (the longest one) wins</li>
  *   <li><code>request.pagePath</code> is set to path of your handler (/foo), <code>request.pathTail</code> is set to the rest(/bar).</li>
  *   <li><code>request.fullPath</code> contains the full path in decoded form</li>
  *   <li>request.fullPathSegments, request.pagePathSegments and request.pathTailSegments contain segments of these paths</li>
  * </li></ul>
  * <li>404 handling is different: assign your 404 handler to dispatchPlus.f404</li>
  * <li>If you pass arguments to dispatchPlus call, they are passed to handler function. No more need for globals to pass initial information to handler functions.</li>
  * </ul>
  */
function dispatchPlus(arg1, arg2, etc) {
    _rejuvenateFullPathSegments();
    var selectorSegments = request.fullPathSegments.map(function(x) {
        return [x.replace(/[\W]/g,'$$'), "_"];
    });
    selectorSegments.push([selectorSegments.pop()[0] || "main"]);

    var handler, handlerSegments, selector = arguments.callee[request.method] || request.method.toLowerCase();
    selectorSegments.forEach(function(segment, index) {
        selector += segment.join('');
        var candidate = appjet._internal.global[selector];
        if (typeof candidate === "function") {
        	handler = candidate;
        	handlerSegments = index + 1;
        }
    });

    if (handler) {
        request.pagePathSegments = request.fullPathSegments.slice(0, handlerSegments);
        request.pathTailSegments = request.fullPathSegments.slice(handlerSegments);
        request.pagePath = request.pagePathSegments.join('/');
        request.pathTail = request.fullPath.substring(request.pagePath.length);
    }
    (handler || arguments.callee.f404).apply(null, arguments);
}

/** The 404 (page not found) handler. You can replace it with your own. */
dispatchPlus.f404 = function() {
    response.setStatusCode(404);
    printp("Path not found: ", request.fullPath);
    print(request);
    response.stop();
};

/** The prefix for GET method dispatcher functions. Default is "get", you can change it. */
dispatchPlus.GET = "get";

/** The prefix for HEAD method dispatcher functions. Default is "get", you can change it. */
dispatchPlus.HEAD = "get";

/** The prefix for POST method dispatcher functions. Default is "post", you can change it. */
dispatchPlus.POST = "post";

/** The prefix for CRON method dispatcher functions. Default is "cron", you can change it. */
dispatchPlus.CRON = "cron";

function _rejuvenateFullPathSegments() {
    if (request.fullPathSegments.of === request.fullPath) return;
    request.fullPathSegments = request.fullPath.split('/');
    request.fullPathSegments.of = request.fullPath;
}

/* appjet:server */

import("lib-app/dispatch-plus");

/**@ignore*/
function printRequest() {
    printp({
        pagePath: request.pagePath,
        pagePathSegments: request.pagePathSegments,
        fullPath: request.fullPath,
        fullPathSegments: request.fullPathSegments,
        pathTail: request.pathTail,
        pathTailSegments: request.pathTailSegments
    });
};

/**@ignore*/
function get_(arg) {
    printp("Serviced by ", CODE(arguments.callee));
    printp("Try these links:");
    print(UL(
        LI(A({href:"/long/path/here.2"}, "/long/path/here.2")),
        LI(A({href:"/papľuh/path-ing/"}, "/papľuh/path-ing/"))
    ));
    printp("Hello, ", arg, "!");
    printRequest();
}

/**@ignore*/
function get_papľuh_(arg) {
    printp("Serviced by ", CODE(arguments.callee));
    printp("Hello, ", arg, "!");
    printRequest();
}

/**@ignore*/
var get_papľuh_path$ing = "This is not a function";

/**@ignore*/
function get_long_path_() {
    throw new Error("This should not be called.");
}

/**@ignore*/
function get_long_path_here$2(arg) {
    printp("Serviced by ", CODE(arguments.callee));
    printp("Hello, ", arg, "!");
    printRequest();
}

/**@ignore*/
function get_long_path_here$2_() {
    throw new Error("This should not be called.");
}

/**@ignore*/
function get_long_path_here$2_main() {
    throw new Error("This should not be called.");
}

printp("Features of extended dispatcher:");
print(UL(
    LI("Any nonalphanumeric characters (except the slash, of course) are replaced by '$' (dollar sign). Now you can serve /robots.txt by get_robots$txt function."),
    LI("You can put a handler only to a beginning part of the path, if you use name like get_beginning_. This serves all paths in the form /beginning/... The path is broken to request.pagePath (the first part) and request.pathTail (the rest)."),
    LI("If you end function with _main, it will not serve subpaths (it only matches to full path ending with / (a slash)."),
    LI("If there are more subpath handlers and full path handlers, the most specific (the one that matches the longest part of the path) is chosen. If case of get_path_ and get_path_main, the latter will be chosen to service /path/, but the former to service /path/some/more."),
    LI("404 is handled other way: you specify your 404 handler by assigning it to dispatchPlus.f404 before placing a call."),
    LI("Any arguments you put in dispatchPlus call, gets copied into your handler function.")
));
printp("The statments issued in this minitest is ", CODE('dispatchPlus("world")'));


dispatchPlus("world");