Allow the app to change the $location path while rendering.

This gets handled as a HTTP redirect. In the present implementation this
is a bit wasteful because it will still completely render the page even
though the body isn't actually returned.

Author: apparentlymart

lib/main.js

@@ -60,6 +60,27 @@ function handleRequest(template, context, modules, request, response) {
         link($rootScope);
 
         var onceRouteKnown = function (route) {
+
+            if (reqContext.getRedirectTo()) {
+                // The path changed while we were rendering, so emit a redirect.
+                // FIXME: Find some way to do this without actually doing the work to render
+                // the route. Probably will need to do route resolution manually, then.
+                response.writeHead(
+                    302,
+                    {
+                        Location: reqContext.getRedirectTo()
+                    }
+                );
+                response.end(reqContext.getRedirectTo());
+                // still need to clean up the context once everything's settled.
+                $httpBackend.notifyWhenNoOpenRequests(
+                    function () {
+                        context.dispose();
+                    }
+                );
+                return;
+            }
+
             // Stash any controller locals we pre-resolved so we can return them
             // to the client as a sort of cache so the browser can avoid additional round-trips.
             var preResolved = {};
@@ -73,7 +94,6 @@ function handleRequest(template, context, modules, request, response) {
 
             $httpBackend.notifyWhenNoOpenRequests(
                 function () {
-                    // once more for luck
                     $rootScope.$digest();
 
                     response.writeHead(200);

lib/ngoverrides.js

@@ -8,9 +8,10 @@ function registerModule(context) {
 
     module.factory(
         'serverRequestContext',
-        function () {
+        function ($rootScope) {
             var request;
             var requestUrlParts;
+            var redirectTo;
 
             var ifRequest = function (code) {
                 return function () {
@@ -23,30 +24,33 @@ function registerModule(context) {
                 };
             };
             var parsedUrl = function (code) {
-                return function () {
+                return function (set) {
                     if (request) {
                         if (! requestUrlParts) {
                             requestUrlParts = url.parse(request.url, true);
                         }
-                        return code(requestUrlParts);
+                        return code(requestUrlParts, set);
                     }
                     else {
                         return undefined;
                     }
                 };
             };
 
+            var absUrl = parsedUrl(
+                function (parts) {
+                    // TODO: Make this be https: when the
+                    // request is SSL?
+                    return 'http://' +
+                        request.headers.host +
+                        parts.pathname +
+                        (parts.search ? parts.search : '');
+                }
+            );
+
             return {
                 location: {
-                    absUrl: ifRequest(
-                        function () {
-                            // TODO: Make this be https: when the
-                            // request is SSL?
-                            return 'http://' +
-                                request.headers.host +
-                                request.url;
-                        }
-                    ),
+                    absUrl: absUrl,
                     hash: function () {
                         // the server never sees the fragment
                         return '';
@@ -57,7 +61,21 @@ function registerModule(context) {
                         }
                     ),
                     path: parsedUrl(
-                        function (parts) {
+                        function (parts, set) {
+                            if (set) {
+                                var oldUrl = absUrl();
+                                $rootScope.$apply(
+                                    function () {
+                                        parts.pathname = set;
+                                        redirectTo = absUrl();
+                                        $rootScope.$broadcast(
+                                            '$locationChangeSuccess',
+                                            redirectTo,
+                                            oldUrl
+                                        );
+                                    }
+                                );
+                            }
                             return parts.pathname;
                         }
                     ),
@@ -87,6 +105,9 @@ function registerModule(context) {
                     else {
                         request = newRequest;
                     }
+                },
+                getRedirectTo: function () {
+                    return redirectTo;
                 }
             };
         }