diff --git a/cps/db.py b/cps/db.py
index f5fbcbbf..c6e069e5 100755
--- a/cps/db.py
+++ b/cps/db.py
@@ -264,7 +264,7 @@ class Books(Base):
 
 class Custom_Columns(Base):
     __tablename__ = 'custom_columns'
-    
+
     id = Column(Integer, primary_key=True)
     label = Column(String)
     name = Column(String)
diff --git a/cps/epub.py b/cps/epub.py
index 446efe9b..8d0b2817 100644
--- a/cps/epub.py
+++ b/cps/epub.py
@@ -57,7 +57,7 @@ def get_epub_info(tmp_file_path, original_file_name, original_file_extension):
             epub_metadata['description'] = ""
 
     if epub_metadata['language'] == "Unknown":
-        epub_metadata['language'] == ""
+        epub_metadata['language'] = ""
     else:
         lang = epub_metadata['language'].split('-', 1)[0].lower()
         if len(lang) == 2:
@@ -87,7 +87,7 @@ def get_epub_info(tmp_file_path, original_file_name, original_file_extension):
                     coverfile = extractCover(zip, filename, "", tmp_file_path)
                 else:
                     coverfile = extractCover(zip, coversection[0], coverpath, tmp_file_path)
-            
+
     if epub_metadata['title'] is None:
         title = original_file_name
     else:
diff --git a/cps/helper.py b/cps/helper.py
index 68f1a296..577fa826 100755
--- a/cps/helper.py
+++ b/cps/helper.py
@@ -277,12 +277,12 @@ def update_dir_stucture(book_id, calibrepath):
     db.session.connection().connection.connection.create_function("title_sort", 1, db.title_sort)
     book = db.session.query(db.Books).filter(db.Books.id == book_id).first()
     path = os.path.join(calibrepath, book.path)#.replace('/',os.path.sep)).replace('\\',os.path.sep)
-    
+
     authordir = book.path.split('/')[0]
     new_authordir = get_valid_filename(book.authors[0].name)
     titledir = book.path.split('/')[1]
     new_titledir = get_valid_filename(book.title) + " (" + str(book_id) + ")"
-    
+
     if titledir != new_titledir:
         new_title_path = os.path.join(os.path.dirname(path), new_titledir)
         os.rename(path, new_title_path)
@@ -348,7 +348,7 @@ class Updater(threading.Thread):
         if web.gevent_server:
             web.gevent_server.stop()
         else:
-            # stop tornado server            
+            # stop tornado server
             server = IOLoop.instance()
             server.add_callback(server.stop)
         self.status=7
diff --git a/cps/static/js/edit_books.js b/cps/static/js/edit_books.js
index e81a88b2..12199c0d 100644
--- a/cps/static/js/edit_books.js
+++ b/cps/static/js/edit_books.js
@@ -17,8 +17,8 @@ function prefixed_source(prefix, query, cb, bhAdapter) {
     });
 }
 function get_path(){
-    var jsFileLocation = $('script[src*=edit_books]').attr('src');  // the js file path
-    jsFileLocation = jsFileLocation.replace('/static/js/edit_books.js', '');   // the js folder path
+    var jsFileLocation = $("script[src*=edit_books]").attr("src");  // the js file path
+    jsFileLocation = jsFileLocation.replace("/static/js/edit_books.js", '');   // the js folder path
     return jsFileLocation;
 }
 
@@ -29,7 +29,7 @@ var authors = new Bloodhound({
     },
     queryTokenizer: Bloodhound.tokenizers.whitespace,
     remote: {
-        url: get_path()+'/get_authors_json?q=%QUERY'
+        url: get_path()+"/get_authors_json?q=%QUERY"
     }
 });
 
@@ -58,7 +58,8 @@ var promise = authors.initialize();
                 highlight: true, minLength: 1,
                 hint: true
             }, {
-                name: 'authors', displayKey: 'name',
+                name: "authors",
+                displayKey: "name",
                 source: authors_source
             }
     )
@@ -73,10 +74,9 @@ var series = new Bloodhound({
         return [query];
     },
     remote: {
-        url: get_path()+'/get_series_json?q=',
+        url: get_path()+"/get_series_json?q=",
         replace: function(url, query) {
-            url_query = url+encodeURIComponent(query);
-            return url_query;
+            return url+encodeURIComponent(query);
         }
     }
 });
@@ -87,7 +87,8 @@ var promise = series.initialize();
                 highlight: true, minLength: 0,
                 hint: true
             }, {
-                name: 'series', displayKey: 'name',
+                name: "series",
+                displayKey: "name",
                 source: series.ttAdapter()
             }
     )
@@ -99,9 +100,9 @@ var tags = new Bloodhound({
         return [datum.name];
     },
     queryTokenizer: function(query) {
-        tokens = query.split(",");
+        var tokens = query.split(",");
         tokens = [tokens[tokens.length-1].trim()];
-        return tokens
+        return tokens;
     },
     remote: {
         url: get_path()+"/get_tags_json?q=%QUERY"
@@ -131,7 +132,8 @@ var promise = tags.initialize();
                 highlight: true, minLength: 0,
                 hint: true
             }, {
-                name: 'tags', displayKey: 'name',
+                name: "tags",
+                displayKey: "name",
                 source: tag_source
             }
     )
@@ -146,7 +148,7 @@ var languages = new Bloodhound({
         return [query];
     },
     remote: {
-        url: get_path()+'/get_languages_json?q=',
+        url: get_path()+"/get_languages_json?q=",
         replace: function(url, query) {
             url_query = url+encodeURIComponent(query);
             return url_query;
@@ -177,23 +179,24 @@ var promise = languages.initialize();
                 highlight: true, minLength: 0,
                 hint: true
             }, {
-                name: 'languages', displayKey: 'name',
+                name: "languages",
+                displayKey: "name",
                 source: language_source
             }
     )
 });
 
-$('form').on('change input typeahead:selected', function(data){
-    form = $('form').serialize();
+$("form").on("change input typeahead:selected", function(data){
+    var form = $("form").serialize();
     $.getJSON( get_path()+"/get_matching_tags", form, function( data ) {
-      $('.tags_click').each(function() {
-        if ($.inArray(parseInt($(this).children('input').first().val(), 10), data.tags) == -1 ) {
-          if (!($(this).hasClass('active'))) {
-            $(this).addClass('disabled');
+      $(".tags_click").each(function() {
+        if ($.inArray(parseInt($(this).children("input").first().val(), 10), data.tags) === -1 ) {
+          if (!($(this).hasClass("active"))) {
+            $(this).addClass("disabled");
           }
         }
         else {
-          $(this).removeClass('disabled');
+          $(this).removeClass("disabled");
         }
       });
     });
diff --git a/cps/static/js/get_meta.js b/cps/static/js/get_meta.js
index e58e54bf..f9fa5b60 100644
--- a/cps/static/js/get_meta.js
+++ b/cps/static/js/get_meta.js
@@ -6,33 +6,33 @@
  */
 
 $(document).ready(function () {
-    var msg = i18n_msg;
+    var msg = i18nMsg;
     var douban = "https://api.douban.com";
-    var db_search = '/v2/book/search';
-    var db_get_info = '/v2/book/';
-    var db_get_info_by_isbn = '/v2/book/isbn/ ';
-    var db_done = false;
+    var dbSearch = "/v2/book/search";
+    var db_get_info = "/v2/book/";
+    var db_get_info_by_isbn = "/v2/book/isbn/ ";
+    var dbDone = false;
 
-    var google = 'https://www.googleapis.com/';
-    var gg_search = '/books/v1/volumes';
-    var gg_get_info = '/books/v1/volumes/';
+    var google = "https://www.googleapis.com/";
+    var gg_search = "/books/v1/volumes";
+    var gg_get_info = "/books/v1/volumes/";
     var gg_done = false;
 
     var db_results = [];
     var gg_results = [];
     var show_flag = 0;
     String.prototype.replaceAll = function (s1, s2) {　　
-        return this.replace(new RegExp(s1, "gm"), s2);　　
+        return this.replace(new RegExp(s1, "gm"), s2);
     };
 
-    gg_search_book = function (title) {
-        title = title.replaceAll(/\s+/, '+');
-        var url = google + gg_search + '?q=' + title;
+    function gg_search_book (title) {
+        title = title.replaceAll(/\s+/, "+");
+        var url = google + gg_search + "?q=" + title;
         $.ajax({
-            url: url,
+            url,
             type: "GET",
             dataType: "jsonp",
-            jsonp: 'callback',
+            jsonp: "callback",
             success: function (data) {
                 gg_results = data.items;
             },
@@ -43,15 +43,16 @@ $(document).ready(function () {
         });
     }
 
-    get_meta = function (source, id) {
+    function get_meta (source, id) {
         var meta;
-        if (source == "google") {
+        var tags;
+        if (source === "google") {
             meta = gg_results[id];
             $("#description").val(meta.volumeInfo.description);
-            $("#bookAuthor").val(meta.volumeInfo.authors.join(' & '));
+            $("#bookAuthor").val(meta.volumeInfo.authors.join(" & "));
             $("#book_title").val(meta.volumeInfo.title);
             if (meta.volumeInfo.categories) {
-                var tags = meta.volumeInfo.categories.join(',');
+                tags = meta.volumeInfo.categories.join(",");
                 $("#tags").val(tags);
             }
             if (meta.volumeInfo.averageRating) {
@@ -59,10 +60,10 @@ $(document).ready(function () {
             }
             return;
         }
-        if (source == "douban") {
+        if (source === "douban") {
             meta = db_results[id];
             $("#description").val(meta.summary);
-            $("#bookAuthor").val(meta.author.join(' & '));
+            $("#bookAuthor").val(meta.author.join(" & "));
             $("#book_title").val(meta.title);
             var tags = '';
             for (var i = 0; i < meta.tags.length; i++) {
@@ -84,7 +85,7 @@ $(document).ready(function () {
     }
 
     db_search_book = function (title) {
-        var url = douban + db_search + '?q=' + title + '&fields=all&count=10';
+        var url = douban + dbSearch + '?q=' + title + '&fields=all&count=10';
         $.ajax({
             url: url,
             type: "GET",
@@ -97,18 +98,18 @@ $(document).ready(function () {
                 $('#meta-info').html('<p class="text-danger">'+ msg.search_error+'!</p>');
             },
             complete: function () {
-                db_done = true;
+                dbDone = true;
                 show_result();
             }
         });
     }
 
-    show_result = function () {
+    function show_result () {
         show_flag++;
         if (show_flag == 1) {
             $('#meta-info').html('<ul id="book-list" class="media-list"></ul>');
         }
-        if (gg_done && db_done) {
+        if (gg_done && dbDone) {
             if (!gg_results && !db_results) {
                 $('#meta-info').html('<p class="text-danger">'+ msg.no_result +'</p>');
                 return;
@@ -140,7 +141,7 @@ $(document).ready(function () {
             }
             gg_done = false;
         }
-        if (db_done && db_results.length > 0) {
+        if (dbDone && db_results.length > 0) {
             for (var i = 0; i < db_results.length; i++) {
                 var book = db_results[i];
                 var book_html = '<li class="media">' +
@@ -155,24 +156,24 @@ $(document).ready(function () {
                     '<p>' + msg.description + ':' + book.summary + '</p>' +
                     '<p>' + msg.source + ':<a href="https://book.douban.com" target="_blank">Douban Books</a></p>' +
                     '</div>' +
-                    '</li>';
+                    "</li>";
                 $("#book-list").append(book_html);
             }
-            db_done = false;
+            dbDone = false;
         }
     }
 
-    $('#do-search').click(function () {
-        var keyword = $('#keyword').val();
+    $("#do-search").click(function () {
+        var keyword = $("#keyword").val();
         if (keyword) {
             do_search(keyword);
         }
     });
 
-    $('#get_meta').click(function () {
-        var book_title = $('#book_title').val();
+    $("#get_meta").click(function () {
+        var book_title = $("#book_title").val();
         if (book_title) {
-            $('#keyword').val(book_title);
+            $("#keyword").val(book_title);
             do_search(book_title);
         }
     });
diff --git a/cps/static/js/main.js b/cps/static/js/main.js
index c18f85e5..c20bd44a 100644
--- a/cps/static/js/main.js
+++ b/cps/static/js/main.js
@@ -3,7 +3,7 @@ var updateTimerID;
 var updateText;
 
 $(function() {
-    $('.discover .row').isotope({
+    $(".discover .row").isotope({
         // options
         itemSelector : ".book",
         layoutMode : "fitRows"
@@ -20,28 +20,28 @@ $(function() {
         extraScrollPx: 300,
                    // selector for all items you'll retrieve
     }, function(data){
-        $(".load-more .row").isotope( 'appended', $(data), null );
+        $(".load-more .row").isotope( "appended", $(data), null );
     });
 
-    $('#sendbtn').click(function(){
+    $("#sendbtn").click(function(){
         var $this = $(this);
         $this.text("Please wait...");
         $this.addClass("disabled");
     });
     $("#restart").click(function() {
         $.ajax({
-            dataType: 'json',
+            dataType: "json",
             url: window.location.pathname+"/../../shutdown",
             data: {"parameter":0},
             success: function(data) {
-                $('#spinner').show();
+                $("#spinner").show();
                 displaytext=data.text;
                 setTimeout(restartTimer, 3000);}
         });
     });
     $("#shutdown").click(function() {
         $.ajax({
-            dataType: 'json',
+            dataType: "json",
             url: window.location.pathname+"/../../shutdown",
             data: {"parameter":1},
             success: function(data) {
@@ -50,13 +50,13 @@ $(function() {
     });
     $("#check_for_update").click(function() {
         var button_text = $("#check_for_update").html();
-        $("#check_for_update").html('...');
+        $("#check_for_update").html("...");
         $.ajax({
-            dataType: 'json',
+            dataType: "json",
             url: window.location.pathname+"/../../get_update_status",
             success: function(data) {
                 $("#check_for_update").html(button_text);
-                if (data.status == true) {
+                if (data.status === true) {
                     $("#check_for_update").addClass("hidden");
                     $("#perform_update").removeClass("hidden");
                     $("#update_info").removeClass("hidden");
@@ -82,13 +82,12 @@ $(function() {
         success: function(data) {
             updateText=data.text;
             $("#UpdateprogressDialog #Updatecontent").html(updateText[data.status]);
-            console.log(data.status);
+            // console.log(data.status);
             updateTimerID=setInterval(updateTimer, 2000);}
         });
     });
 });
 
-
 function restartTimer() {
     $("#spinner").hide();
     $("#RestartDialog").modal("hide");
@@ -103,10 +102,10 @@ function updateTimer() {
         $("#UpdateprogressDialog #Updatecontent").html(updateText[data.status]);
         if (data.status >6){
             clearInterval(updateTimerID);
-            $('#spinner2').hide();
-            $('#UpdateprogressDialog #updateFinished').removeClass('hidden');
-            $("#check_for_update").removeClass('hidden');
-            $("#perform_update").addClass('hidden');
+            $("#spinner2").hide();
+            $("#UpdateprogressDialog #updateFinished").removeClass("hidden");
+            $("#check_for_update").removeClass("hidden");
+            $("#perform_update").addClass("hidden");
         }
     },
     error: function() {
diff --git a/cps/static/js/shelforder.js b/cps/static/js/shelforder.js
index ea970f9a..3102f080 100644
--- a/cps/static/js/shelforder.js
+++ b/cps/static/js/shelforder.js
@@ -1,4 +1,4 @@
-Sortable.create(sortTrue, {
+var sortable = Sortable.create(sortTrue, {
   group: "sorting",
   sort: true
 });
@@ -9,7 +9,7 @@ function sendData(path){
     var maxElements;
     var tmp=[];
 
-    elements=Sortable.utils.find(sortTrue,"div");
+    elements=sortable.utils.find(sortTrue,"div");
     maxElements=elements.length;
 
     var form = document.createElement("form");
diff --git a/cps/templates/book_edit.html b/cps/templates/book_edit.html
index 474cfaae..165512c7 100644
--- a/cps/templates/book_edit.html
+++ b/cps/templates/book_edit.html
@@ -138,7 +138,7 @@
 
 {% block js %}
 <script>
-  var i18n_msg = {
+  var i18nMsg = {
     'loading': {{_('Loading...')|safe|tojson}},
     'search_error': {{_('Search error!')|safe|tojson}},
     'no_result': {{_('No Result! Please try anonther keyword.')|safe|tojson}},
diff --git a/cps/ub.py b/cps/ub.py
index f2dae60b..d850946a 100644
--- a/cps/ub.py
+++ b/cps/ub.py
@@ -508,7 +508,6 @@ def create_anonymous_user():
         session.commit()
     except Exception:
         session.rollback()
-        pass
 
 
 # Generate User admin with admin123 password, and access to everything
@@ -525,7 +524,7 @@ def create_admin_user():
     session.add(user)
     try:
         session.commit()
-    except Exception as e:
+    except Exception:
         session.rollback()
         pass