From 9ffb1a062f6bfa4c3253eb40c89ba54e6e429fe4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Samy=20Pess=C3=A9?= <samypesse@gmail.com>
Date: Sun, 6 Apr 2014 17:13:10 -0700
Subject: [PATCH] Use cache in localstorage to store search index

---
 lib/generate/site/index.js      |  3 +++
 theme/assets/app.js             | 26 ++++++++++++++++++++------
 theme/javascript/core/search.js | 23 ++++++++++++++++++-----
 theme/javascript/core/state.js  |  3 ++-
 theme/templates/site.html       |  2 +-
 5 files changed, 44 insertions(+), 13 deletions(-)

diff --git a/lib/generate/site/index.js b/lib/generate/site/index.js
index 474de2aab..8b080f243 100644
--- a/lib/generate/site/index.js
+++ b/lib/generate/site/index.js
@@ -26,6 +26,7 @@ var Generator = function() {
     // Attach methods to instance
     _.bindAll(this);
 
+    this.revision = Date.now();
     this.indexer = indexer();
 
     // Load base template
@@ -41,6 +42,8 @@ Generator.prototype._writeTemplate = function(tpl, options, output) {
     return Q()
     .then(function(sections) {
         return tpl(_.extend({
+            revision: that.revision,
+
             title: that.options.title,
             description: that.options.description,
 
diff --git a/theme/assets/app.js b/theme/assets/app.js
index ec6285ff5..f2956de43 100644
--- a/theme/assets/app.js
+++ b/theme/assets/app.js
@@ -18089,7 +18089,8 @@ define('core/state',[
 
         'githubId': $book.data("github"),
         'level': $book.data("level"),
-        'basePath': $book.data("basepath")
+        'basePath': $book.data("basepath"),
+        'revision': $book.data("revision")
     };
 });
 /*global define:false */
@@ -21009,19 +21010,32 @@ define('core/search',[
     "jQuery",
     "lodash",
     "lunr",
+    "utils/storage",
     "core/state",
     "core/sidebar"
-], function($, _, lunr, state, sidebar) {
+], function($, _, lunr, storage, state, sidebar) {
     var index = null;
     var $searchBar = state.$book.find(".book-search");
     var $searchInput = $searchBar.find("input");
 
+    // Use a specific idnex
+    var useIndex = function(data) {
+        index = lunr.Index.load(data);
+    };
+
     // Load complete index
     var loadIndex = function() {
-        return $.getJSON(state.basePath+"/search_index.json")
-        .then(function(data) {
-            index = lunr.Index.load(data);
-        });
+        var cacheKey = state.revision+":"+"searchIndex";
+        var cache = storage.get(cacheKey);
+
+        if (cache) return useIndex(cache);
+
+        $.getJSON(state.basePath+"/search_index.json")
+        .then(function(index) {
+            storage.set(cacheKey, index);
+            return index;
+        })
+        .then(useIndex);
     };
 
     // Search for a term
diff --git a/theme/javascript/core/search.js b/theme/javascript/core/search.js
index a5399d996..bc1a31b3b 100644
--- a/theme/javascript/core/search.js
+++ b/theme/javascript/core/search.js
@@ -2,19 +2,32 @@ define([
     "jQuery",
     "lodash",
     "lunr",
+    "utils/storage",
     "core/state",
     "core/sidebar"
-], function($, _, lunr, state, sidebar) {
+], function($, _, lunr, storage, state, sidebar) {
     var index = null;
     var $searchBar = state.$book.find(".book-search");
     var $searchInput = $searchBar.find("input");
 
+    // Use a specific idnex
+    var useIndex = function(data) {
+        index = lunr.Index.load(data);
+    };
+
     // Load complete index
     var loadIndex = function() {
-        return $.getJSON(state.basePath+"/search_index.json")
-        .then(function(data) {
-            index = lunr.Index.load(data);
-        });
+        var cacheKey = state.revision+":"+"searchIndex";
+        var cache = storage.get(cacheKey);
+
+        if (cache) return useIndex(cache);
+
+        $.getJSON(state.basePath+"/search_index.json")
+        .then(function(index) {
+            storage.set(cacheKey, index);
+            return index;
+        })
+        .then(useIndex);
     };
 
     // Search for a term
diff --git a/theme/javascript/core/state.js b/theme/javascript/core/state.js
index 5ed11e8a9..79876b95c 100644
--- a/theme/javascript/core/state.js
+++ b/theme/javascript/core/state.js
@@ -8,6 +8,7 @@ define([
 
         'githubId': $book.data("github"),
         'level': $book.data("level"),
-        'basePath': $book.data("basepath")
+        'basePath': $book.data("basepath"),
+        'revision': $book.data("revision")
     };
 });
\ No newline at end of file
diff --git a/theme/templates/site.html b/theme/templates/site.html
index 5bb3c8b67..5771c729f 100644
--- a/theme/templates/site.html
+++ b/theme/templates/site.html
@@ -2,7 +2,7 @@
 
 {% block title %}{{ progress.current.title }}{% parent %}{% endblock %}
 {% block content %}
-<div class="book" data-github="{{ githubId }}" data-level="{{ progress.current.level }}" data-basepath="{{ basePath }}">
+<div class="book" data-github="{{ githubId }}" data-level="{{ progress.current.level }}" data-basepath="{{ basePath }}" data-revision="{{ revision }}">
     {% include "includes/book/header.html" %}
     {% include "includes/book/summary.html" %}
     <div class="book-body" tabindex="-1">