add versioning and migrateing data

library/controllers/index-db-controller.js

@@ -23,20 +23,25 @@ module.exports = class IndexDbController extends EventEmitter {
       }
       dbOpenRequest.onsuccess = (event) => {
         this.db = dbOpenRequest.result
-        if (!this.db.objectStoreNames.length) {
-          Object.keys(this.initialState).forEach((key) => {
-            this._add(key, this.initialState[key])
-          })
-        }
         this.emit('success')
         resolve(this.db)
       }
       dbOpenRequest.onupgradeneeded = (event) => {
-        // if (this.migrators)
         this.db = event.target.result
-        this.migrate()
+        this.db.createObjectStore('dataStore')
       }
     })
+    .then((openRequest) => {
+      return this.get('dataStore')
+    })
+    .then((data) => {
+      if (!data) {
+        return this._add('dataStore', this.initialState)
+          .then(() => this.get('dataStore'))
+          .then((versionedData) => Promise.resolve(versionedData.data))
+      }
+      return Promise.resolve(data)
+    })
   }
 
   requestObjectStore (key, type = 'readonly') {
@@ -47,7 +52,7 @@ module.exports = class IndexDbController extends EventEmitter {
     })
   }
 
-  get (key) {
+  get (key = 'dataStore') {
     return this.requestObjectStore(key)
     .then((dataObject)=> {
         return new Promise((resolve, reject) => {
@@ -67,10 +72,6 @@ module.exports = class IndexDbController extends EventEmitter {
     })
   }
 
-  migrate () {
-    this.db.createObjectStore('dataStore')
-  }
-
   _add (key, objStore, cb = logger) {
     return this.requestObjectStore(key, 'readwrite')
     .then((dataObject)=> {

library/sw-core.js

@@ -59,12 +59,6 @@ const dbController = new DbController({
   key: STORAGE_KEY,
   global: self,
   version: 2,
-  initialState: {
-    dataStore: {
-      meta: 2,
-      data: firstTimeState,
-    },
-  },
 })
 asyncQ.waterfall([
   () => loadStateFromPersistence(),
@@ -87,38 +81,14 @@ function loadStateFromPersistence() {
   const initialState = migrator.generateInitialState(firstTimeState)
   dbController.initialState = initialState
   return dbController.open()
-  .then((openRequest) => {
+  .then((versionedData) => migrator.migrateData(versionedData))
-    return dbController.get('dataStore')
+  .then((versionedData) => {
+    dbController.put(versionedData)
+    return Promise.resolve(versionedData)
   })
-  .then((data) => {
-    if (!data) {
-      return dbController._add('dataStore', initialState)
-      .then(() => dbController.get('dataStore'))
   .then((versionedData) => Promise.resolve(versionedData.data))
 }
 
-    return Promise.resolve(data.data)
-  })
-  .catch((err) => console.error(err))
-  /*
-    need to get migrations working
-  */
-
-  // return asyncQ.waterfall([
-  //   // read from disk
-  //   () => Promise.resolve(diskStore || initialState),
-  //   // migrate data
-  //   (versionedData) => migrator.migrateData(versionedData),
-  //   // write to disk
-  //   (versionedData) => {
-  //     diskStore.put(versionedData)
-  //     return Promise.resolve(versionedData)
-  //   },
-  //   // resolve to just data
-  //   (versionedData) => Promise.resolve(versionedData.data),
-  // ])
-}
-
 function setupController (initState, client) {
 
   //
@@ -142,14 +112,20 @@ function setupController (initState, client) {
   //   diskStore
   // )
   controller.store.subscribe((state) => {
-    dbController.put(versionifyData(state))
+    versionifyData(state)
+    .then((versionedData) => dbController.put(versionedData))
     .catch((err) => {console.error(err)})
   })
   function versionifyData(state) {
-    // let versionedData = diskStore.getState()
+    // let versionedData
     // versionedData.data = state
-    let versionedData = {data: state}
+    return dbController.get()
-    return versionedData
+    .then((rawData) => {
+      return Promise.resolve({
+        data: state,
+        meta: rawData.meta,
+      })}
+    )
   }
 
   //