Only create stores for enabled docs in IndexedDB

Ref #25.

assets/javascripts/app/app.coffee

@@ -16,6 +16,7 @@
     @store = new Store
     @appCache = new app.AppCache if app.AppCache.isEnabled()
     @settings = new app.Settings @store
+    @db = new app.DB()
 
     @docs = new app.collections.Docs
     @disabledDocs = new app.collections.Docs
@@ -86,7 +87,6 @@
     @entries.add doc.toEntry() for doc in @docs.all()
     @entries.add doc.toEntry() for doc in @disabledDocs.all()
     @initDoc(doc) for doc in @docs.all()
-    @db = new app.DB()
     @trigger 'ready'
     @router.start()
     @hideLoading()
@@ -125,6 +125,7 @@
 
   saveDocs: ->
     @settings.setDocs(doc.slug for doc in @docs.all())
+    @db.migrate()
     @appCache?.updateInBackground()
 
   welcomeBack: ->

assets/javascripts/app/db.coffee

@@ -3,7 +3,7 @@ class app.DB
 
   constructor: ->
     @useIndexedDB = @useIndexedDB()
-    @indexedDBVersion = @indexedDBVersion()
+    @appVersion = @appVersion()
     @callbacks = []
 
   db: (fn) ->
@@ -13,7 +13,7 @@ class app.DB
 
     try
       @open = true
-      req = indexedDB.open(NAME, @indexedDBVersion)
+      req = indexedDB.open(NAME, @schemaVersion())
       req.onsuccess = @onOpenSuccess
       req.onerror = @onOpenError
       req.onupgradeneeded = @onUpgradeNeeded
@@ -59,14 +59,16 @@ class app.DB
   onUpgradeNeeded: (event) ->
     return unless db = event.target.result
 
-    unless db.objectStoreNames.contains('docs')
+    objectStoreNames = $.makeArray(db.objectStoreNames)
+
+    unless $.arrayDelete(objectStoreNames, 'docs')
       db.createObjectStore('docs')
 
-    for doc in app.docs.all() when not db.objectStoreNames.contains(doc.slug)
+    for doc in app.docs.all() when not $.arrayDelete(objectStoreNames, doc.slug)
       db.createObjectStore(doc.slug)
 
-    for doc in app.disabledDocs.all() when not db.objectStoreNames.contains(doc.slug)
+    for name in objectStoreNames
-      db.createObjectStore(doc.slug)
+      db.deleteObjectStore(name)
     return
 
   store: (doc, data, onSuccess, onError) ->
@@ -201,6 +203,11 @@ class app.DB
         onError()
         return
 
+      unless db.objectStoreNames.contains(entry.doc.slug)
+        onError()
+        @loadDocsCache(db)
+        return
+
       txn = @idbTransaction db, stores: [entry.doc.slug], mode: 'readonly'
       store = txn.objectStore(entry.doc.slug)
 
@@ -212,10 +219,11 @@ class app.DB
         event.preventDefault()
         onError()
         return
-      @loadDocsCache(db) unless @cachedDocs
+      @loadDocsCache(db)
       return
 
   loadDocsCache: (db) ->
+    return if @cachedDocs
     @cachedDocs = {}
 
     txn = @idbTransaction db, stores: ['docs'], mode: 'readonly'
@@ -261,5 +269,15 @@ class app.DB
     catch
       false
 
-  indexedDBVersion: ->
+  migrate: ->
-    if app.config.env is 'production' then parseInt(app.config.version, 10) else Date.now() / 1000
+    app.settings.set('schema', @userVersion() + 1)
+    return
+
+  schemaVersion: ->
+    @appVersion * 10 + @userVersion()
+
+  userVersion: ->
+    app.settings.get('schema')
+
+  appVersion: ->
+    if app.config.env is 'production' then parseInt(app.config.version, 10) else Math.floor(Date.now() / 1000)

assets/javascripts/app/settings.coffee

@@ -5,18 +5,19 @@ class app.Settings
   LAYOUT_KEY = 'layout'
   SIZE_KEY = 'size'
 
-  @defaults: ->
+  @defaults:
     count: 0
     hideDisabled: false
     hideIntro: false
     news: 0
     autoUpdate: true
+    schema: 0
 
   constructor: (@store) ->
     @create() unless @settings = @store.get(SETTINGS_KEY)
 
   create: ->
-    @settings = @constructor.defaults()
+    @settings = $.extend({}, @constructor.defaults)
     @applyLegacyValues @settings
     @save()
     return
@@ -35,7 +36,7 @@ class app.Settings
     @save()
 
   get: (key) ->
-    @settings[key]
+    @settings[key] ? @constructor.defaults[key]
 
   hasDocs: ->
     try !!Cookies.get DOCS_KEY

assets/javascripts/lib/util.coffee

@@ -239,6 +239,14 @@ $.makeArray = (object) ->
   else
     Array::slice.apply(object)
 
+$.arrayDelete = (array, object) ->
+  index = array.indexOf(object)
+  if index >= 0
+    array.splice(index, 1)
+    true
+  else
+    false
+
 # Returns true if the object is an array or a collection of DOM elements.
 $.isCollection = (object) ->
   Array.isArray(object) or typeof object?.item is 'function'

assets/javascripts/views/sidebar/doc_picker.coffee

@@ -50,7 +50,9 @@ class app.views.DocPicker extends app.View
       app.settings.setDocs(docs)
       @saveLink.textContent = if app.appCache then 'Downloading\u2026' else 'Saving\u2026'
       disabledDocs = new app.collections.Docs(doc for doc in app.docs.all() when docs.indexOf(doc.slug) is -1)
-      disabledDocs.uninstall -> app.reload()
+      disabledDocs.uninstall ->
+        app.db.migrate()
+        app.reload()
     return
 
   getSelectedDocs: ->