docs - follow a version throughout the site

fixes googleapis#548

Author: stephenplusplus

docs/site/components/docs/docs-services.js

@@ -1,9 +1,13 @@
 angular.module('gcloud.docs')
-  .factory('getLinks', function(versions, pages) {
+  .factory('getLinks', function($rootScope, versions, pages) {
     'use strict';
 
     // `version` is the current version being browsed.
     return function(version) {
+      if (!version) {
+        version = $rootScope.ACTIVE_VERSION || $rootScope.latestVersion;
+      }
+
       var baseUrl = '#/docs/' + version;
       var VERSIONS = pages.VERSIONS;
 

docs/site/components/docs/docs.js

@@ -256,10 +256,6 @@ angular
       return a.constructor ? -1: a.name > b.name ? 1 : -1;
     }
 
-    function getLinks($route, getLinks) {
-      return getLinks($route.current.params.version);
-    }
-
     $routeProvider
       .when('/docs', {
         redirectTo: '/docs/' + versions[0]
@@ -271,17 +267,17 @@ angular
       .when('/docs/:version', {
         controller: 'DocsCtrl',
         templateUrl: 'site/components/docs/docs.html',
-        resolve: { methods: getMethods, links: getLinks }
+        resolve: { methods: getMethods }
       })
       .when('/docs/:version/:module', {
         controller: 'DocsCtrl',
         templateUrl: 'site/components/docs/docs.html',
-        resolve: { methods: getMethods, links: getLinks }
+        resolve: { methods: getMethods }
       })
       .when('/docs/:version/:module/:class', {
         controller: 'DocsCtrl',
         templateUrl: 'site/components/docs/docs.html',
-        resolve: { methods: getMethods, links: getLinks }
+        resolve: { methods: getMethods }
       });
   })
 
@@ -290,22 +286,27 @@ angular
 
     $rootScope.$on('$routeChangeStart', function(event, route) {
       var url = $location.path();
+
       if (url.indexOf('/docs/') === -1 || (!route.params || !route.params.version)) {
         // This isn't a `docs` route or it's not one that expects a version.
         // No need to re-direct request.
         return;
       }
+
       if (versions.indexOf(route.params.version) === -1) {
         // No version specified where one was expected.
         // Route to same url with latest version prepended.
         event.preventDefault();
         $route.reload();
         $location.path(url.replace('docs/', 'docs/' + versions[0] + '/'));
+        return;
       }
+
+      $rootScope.ACTIVE_VERSION = route.params.version;
     });
   })
 
-  .controller('DocsCtrl', function($location, $scope, $routeParams, methods, $http, links, versions) {
+  .controller('DocsCtrl', function($location, $scope, $routeParams, methods, $http, versions) {
     'use strict';
 
     $scope.isActiveUrl = function(url) {
@@ -340,7 +341,6 @@ angular
     $scope.methods = methods;
     $scope.version = $routeParams.version;
     $scope.versions = versions;
-    $scope.links = links;
   })
 
   .controller('HistoryCtrl', function($scope, versions) {

docs/site/components/subpage/subpage-directive.js

@@ -1,14 +1,14 @@
 angular
   .module('gcloud.subpage', ['gcloud.header'])
-  .directive('subpage', function($location, $parse, getLinks) {
+  .directive('subpage', function($rootScope, $location, $parse, getLinks) {
     'use strict';
 
     return {
       transclude: true,
       templateUrl: 'site/components/subpage/subpage.html',
       link: function($scope, elem, attrs) {
         $scope.title = attrs.title;
-        $scope.links = getLinks('master');
+        $scope.links = getLinks();
         $scope.headerTemplateUrl = attrs.headerTemplateurl;
 
         if (attrs.isActiveUrl) {

docs/site/home.html

@@ -24,7 +24,7 @@ <h2>One-line npm install</h2>
     <div class="container">
       <ul class="featuring-links">
         <li>
-          <a href="#/docs/{{latestVersion}}" title="gcloud-node docs" class="btn btn-docs">
+          <a href="#/docs/{{ACTIVE_VERSION || latestVersion}}" title="gcloud-node docs" class="btn btn-docs">
             <img src="site/img/icon-lang-nodejs.svg" alt="Node.js icon" />
             Read the Docs
           </a>

docs/site/home.js

@@ -20,14 +20,14 @@ angular
       controller: 'HomeCtrl'
     });
   })
-  .controller('HomeCtrl', function($scope, versions) {
+  .controller('HomeCtrl', function() {
     'use strict';
-
-    $scope.latestVersion = versions[0];
   })
-  .run(function($rootScope, $location) {
+  .run(function($rootScope, $location, versions) {
     'use strict';
 
+    $rootScope.latestVersion = versions[0];
+
     $rootScope.$on('$routeChangeStart', function(event) {
       var hash = $location.hash();
       if (hash) {