Fixes blank screen at startup (#1110)

* Removing unneeded code * Checking if DB is writable * Resolving DB sync when database is empty * Enhancing selected tab defaults at startup * Checking for R/W permissions * Restoring log entry * Improving error handling
ethereum · Aug 24, 2016 · 9e6dcbd · 9e6dcbd
1 parent bea7f59
commit 9e6dcbd
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Showing 3 changed files with 28 additions and 47 deletions.
diff --git a/interface/client/appStart.js b/interface/client/appStart.js
@@ -4,11 +4,6 @@
 if(location.hash)
     return;
 
-
-// set browser as default tab
-if(!LocalStore.get('selectedTab'))
-    LocalStore.set('selectedTab', 'wallet');
-
 /**
 The init function of Mist
 
@@ -17,7 +12,6 @@ The init function of Mist
 mistInit = function(){
     console.info('Initialise Mist');
 
-
     Tabs.onceSynced.then(function() {
         if (0 <= location.search.indexOf('reset-tabs')) {
             console.info('Resetting UI tabs');
@@ -35,17 +29,20 @@ mistInit = function(){
             });
         }
 
-
         Tabs.upsert({_id: 'wallet'}, {
             url: 'https://wallet.ethereum.org',
             position: 1,
             permissions: {
                 admin: true
             }
-        });        
-    })
-    .then(function() {
-        window.trigger('mist-ready');
+        });
+
+        // Sets browser as default tab if:
+        // 1) there's no record of selected tab
+        // 2) data is corrupted (no saved tab matches localstore)
+        if(!LocalStore.get('selectedTab') || !Tabs.findOne(LocalStore.get('selectedTab'))){
+            LocalStore.set('selectedTab', 'wallet');
+        }
     });
 };
 

diff --git a/modules/db.js b/modules/db.js
@@ -15,10 +15,8 @@ exports.init = function() {
     return Q.try(() => {
         // if db file doesn't exist then create it
         try {
-            log.debug(`Check that db exists: ${filePath}`);
-
-            fs.accessSync(filePath, fs.R_OK);
-
+            log.debug('Check that db exists and it\'s writeable: ${filePath}');
+            fs.accessSync(filePath, fs.R_OK | fs.W_OK);
             return Q.resolve();
         } catch (err) {
             log.info(`Creating db: ${filePath}`);
@@ -43,10 +41,8 @@ exports.init = function() {
                 autoloadCallback: function(err) {
                     if (err) {
                         log.error(err);
-
                         reject(new Error('Error instantiating db'));
                     }
-
                     resolve();
                 }
             });      

diff --git a/modules/syncMinimongo.js b/modules/syncMinimongo.js
@@ -1,21 +1,15 @@
 /**
 @module syncMinimongo
 */
-
-
 var electron = require('electron');
 
-
-
 /**
  * Sync IPC calls received from given window into given db table.
  * @param  {Object} coll Db collection to save to.
  */
 exports.backendSync = function() {
     var log = require('./utils/logger').create('syncMinimongo');
-
     var db = require('./db');
-
     var ipc = electron.ipcMain;
 
     ipc.on('minimongo-add', function(event, args) {
@@ -28,7 +22,6 @@ exports.backendSync = function() {
 
         if (!coll.findOne({_id: _id})) {
             args.fields._id = _id;
-
             coll.insert(args.fields);
         }
     });
@@ -40,7 +33,6 @@ exports.backendSync = function() {
         log.trace('minimongo-changed', collName, args._id);
 
         var _id = args._id;
-
         var item = coll.findOne({_id: _id});
 
         if (item) {
@@ -61,7 +53,6 @@ exports.backendSync = function() {
         log.trace('minimongo-removed', collName, args._id);
 
         var _id = args._id;
-
         var item = coll.findOne({_id: _id});
 
         if (item) {
@@ -74,9 +65,8 @@ exports.backendSync = function() {
     // get all data (synchronous)
     ipc.on('minimongo-reloadSync', function(event, args) {
         var collName = args.collName,
-            coll = db.getCollection(collName);
-
-        var docs = coll.find();
+            coll = db.getCollection(collName),
+            docs = coll.find();
 
         log.debug('minimongo-reloadSync, no. of docs:', collName, docs.length);
 
@@ -100,34 +90,32 @@ exports.backendSync = function() {
 
 
 exports.frontendSync = function(coll) {
-    var ipc = electron.ipcRenderer;
-
-    var collName = coll._name;
+    var ipc = electron.ipcRenderer,
+        collName = coll._name,
+        syncDoneResolver;
 
     console.debug('Reload collection from backend: ', collName);
 
-    var syncDoneResolver = null;
     coll.onceSynced = new Promise(function(resolve, reject) {
         syncDoneResolver = resolve;
     });
 
-
     (new Promise(function(resolve, reject) {
-        var dataStr = ipc.sendSync('minimongo-reloadSync', {
+        var dataStr, dataJson;
+
+        dataStr = ipc.sendSync('minimongo-reloadSync', {
             collName: collName
         });
 
-        if (!dataStr) {
-            return resolve();
-        }
-
         try {
-            coll.remove({});
-
-            var dataJson = JSON.parse(dataStr);
+            if (!dataStr || (dataJson = JSON.parse(dataStr)).length == 0) {
+                return resolve();
+            }
 
             var done = 0;
 
+            coll.remove({});
+
             // we do inserts slowly, to avoid race conditions when it comes
             // to updating the UI
             dataJson.forEach(function(record) {
@@ -141,9 +129,9 @@ exports.frontendSync = function(coll) {
                             record.redirect = null;
                         }
 
-                        coll.insert(record);                
+                        coll.insert(record);
                     } catch (err) {
-                        console.error(err.toString());                        
+                        console.error(err.toString());
                     }
 
                     done++;
@@ -152,7 +140,7 @@ exports.frontendSync = function(coll) {
                         resolve();
                     }
                 });
-            });                
+            });
         } catch (err) {
             reject(err);
         }        
@@ -163,10 +151,10 @@ exports.frontendSync = function(coll) {
     .then(function() {
         // start watching for changes
         coll.find().observeChanges({
-            'added': function(id, fields){            
+            'added': function(id, fields){
                 ipc.send('minimongo-add', {
                     collName: collName,
-                    _id: id, 
+                    _id: id,
                     fields: fields,
                 });
             },