Add route hooks API (#1253)

* build initial implementation of route hooks

* extend Router with Hooks and register all hooks

* more route hooks tweaks

* router namespace cleanup

* removed unused values from registry entry (linter)

client/modules/router/hooks.js

@@ -0,0 +1,55 @@
+
+/**
+ * Route Hook Methods
+ */
+const Hooks = {
+  _hooks: {
+    onEnter: {},
+    onExit: {}
+  },
+
+  _addHook(type, routeName, callback) {
+    if (typeof this._hooks[type][routeName] === "undefined") {
+      this._hooks[type][routeName] = [];
+    }
+    this._hooks[type][routeName].push(callback);
+  },
+
+  onEnter(routeName, callback) {
+    // global onEnter callback
+    if (arguments.length === 1 && typeof arguments[0] === "function") {
+      const cb = routeName;
+      return this._addHook("onEnter", "GLOBAL", cb);
+    }
+    // route-specific onEnter callback
+    return this._addHook("onEnter", routeName, callback);
+  },
+
+  onExit(routeName, callback) {
+    // global onExit callback
+    if (arguments.length === 1 && typeof arguments[0] === "function") {
+      const cb = routeName;
+      return this._addHook("onExit", "GLOBAL", cb);
+    }
+    // route-specific onExit callback
+    return this._addHook("onExit", routeName, callback);
+  },
+
+  get(type, name) {
+    const group = this._hooks[type] || {};
+    const callbacks = group[name];
+    return (typeof callbacks !== "undefined" && !!callbacks.length) ? callbacks : [];
+  },
+
+  run(type, name, constant) {
+    const callbacks = this.get(type, name);
+    if (typeof callbacks !== "undefined" && !!callbacks.length) {
+      return callbacks.forEach((callback) => {
+        return callback(constant);
+      });
+    }
+    return null;
+  }
+};
+
+export default Hooks;

client/modules/router/main.js

@@ -6,6 +6,7 @@ import { MetaData } from "/lib/api/router/metadata";
 import { Session } from "meteor/session";
 import { Meteor } from "meteor/meteor";
 import { Tracker } from "meteor/tracker";
+import Hooks from "./hooks";
 
 
 // init flow-router
@@ -15,6 +16,8 @@ import { Tracker } from "meteor/tracker";
 // client should wait on subs
 Router.wait();
 
+Router.Hooks = Hooks;
+
 /**
  * checkRouterPermissions
  * check if user has route permissions
@@ -44,8 +47,6 @@ function checkRouterPermissions(context) {
   return context;
 }
 
-// initialize title and meta data and check permissions
-Router.triggers.enter([checkRouterPermissions, MetaData.init]);
 
 /**
  * getRouteName
@@ -192,32 +193,26 @@ Router.initPackageRoutes = () => {
               route,
               template,
               layout,
-              workflow,
-              triggersEnter,
-              triggersExit
+              workflow
             } = registryItem;
-            // get registry route name
-            const routeName = getRegistryRouteName(pkg.name, registryItem);
 
-            // layout option structure
-            const options = {
-              template: template,
-              workflow: workflow,
-              layout: layout
-            };
+            // console.log(registryItem);
+
+            // get registry route name
+            const name = getRegistryRouteName(pkg.name, registryItem);
 
             // define new route
             // we could allow the options to be passed in the registry if we need to be more flexible
             const newRouteConfig = {
-              route: route,
+              route,
               options: {
-                name: routeName,
-                template: options.template,
-                layout: options.layout,
-                triggersEnter: triggersEnter,
-                triggersExit: triggersExit,
-                action: () => {
-                  ReactionLayout(options);
+                name,
+                template,
+                layout,
+                triggersEnter: Router.Hooks.get("onEnter", name),
+                triggersExit: Router.Hooks.get("onExit", name),
+                action() {
+                  ReactionLayout({ template, workflow, layout });
                 }
               }
             };
@@ -307,4 +302,14 @@ Router.isActiveClassName = (routeName) => {
   return routeDef === routeName ? "active" : "";
 };
 
+// Register Global Route Hooks
+Meteor.startup(() => {
+  Router.Hooks.onEnter(checkRouterPermissions);
+  Router.Hooks.onEnter(MetaData.init);
+
+  Router.triggers.enter(Router.Hooks.get("onEnter", "GLOBAL"));
+  Router.triggers.exit(Router.Hooks.get("onExit", "GLOBAL"));
+});
+
+
 export default Router;