From aec3c0b3580da23a767c0a83608170f8a89ce704 Mon Sep 17 00:00:00 2001
From: Maxime Beauchemin <maximebeauchemin@gmail.com>
Date: Sun, 3 Apr 2016 07:37:18 -0700
Subject: [PATCH] Fixing bug when datasource has been deleted

---
 caravel/assets/javascripts/dashboard.js  | 17 +++++++++++------
 caravel/models.py                        | 14 +++++++++-----
 caravel/templates/caravel/dashboard.html | 10 +++++-----
 caravel/views.py                         |  1 -
 caravel/viz.py                           |  2 ++
 5 files changed, 27 insertions(+), 17 deletions(-)

diff --git a/caravel/assets/javascripts/dashboard.js b/caravel/assets/javascripts/dashboard.js
index e3ef7d5457f84..79440d6c40167 100644
--- a/caravel/assets/javascripts/dashboard.js
+++ b/caravel/assets/javascripts/dashboard.js
@@ -21,12 +21,17 @@ var Dashboard = function (dashboardData) {
       var sliceObjects = [],
         dash = this;
       dashboard.slices.forEach(function (data) {
-        var slice = px.Slice(data, dash);
-        $("#slice_" + data.slice_id).find('a.refresh').click(function () {
-          slice.render(true);
-        });
-        sliceObjects.push(slice);
-        slice.render();
+        if (data.error) {
+          var html = '<div class="alert alert-danger">' + data.error + '</div>';
+          $("#slice_" + data.slice_id).find('.token').html(html);
+        } else {
+          var slice = px.Slice(data, dash);
+          $("#slice_" + data.slice_id).find('a.refresh').click(function () {
+            slice.render(true);
+          });
+          sliceObjects.push(slice);
+          slice.render();
+        }
       });
       this.slices = sliceObjects;
     },
diff --git a/caravel/models.py b/caravel/models.py
index e8973c4891606..a7ab6230bfe08 100644
--- a/caravel/models.py
+++ b/caravel/models.py
@@ -151,10 +151,8 @@ def datasource_edit_url(self):
     @utils.memoized
     def viz(self):
         d = json.loads(self.params)
-        viz = viz_types[self.viz_type](
-            self.datasource,
-            form_data=d)
-        return viz
+        viz_class = viz_types[self.viz_type]
+        return viz_class(self.datasource, form_data=d)
 
     @property
     def description_markeddown(self):
@@ -166,7 +164,13 @@ def datasource_id(self):
 
     @property
     def data(self):
-        d = self.viz.data
+        d = {}
+        self.token = ''
+        try:
+            d = self.viz.data
+            self.token = d.get('token')
+        except Exception as e:
+            d['error'] = str(e)
         d['slice_id'] = self.id
         return d
 
diff --git a/caravel/templates/caravel/dashboard.html b/caravel/templates/caravel/dashboard.html
index 9859fc77eb297..52f3645f4ca8c 100644
--- a/caravel/templates/caravel/dashboard.html
+++ b/caravel/templates/caravel/dashboard.html
@@ -72,17 +72,17 @@ <h2>
     <ul>
         {% for slice in dashboard.slices %}
           {% set pos = pos_dict.get(slice.id, {}) %}
-          {% set viz = slice.viz %}
+
 
           <li
             id="slice_{{ slice.id }}"
             slice_id="{{ slice.id }}"
-            class="widget {{ slice.viz.viz_type }}"
+            class="widget {{ slice.viz_type }}"
             data-row="{{ pos.row or 1 }}"
             data-col="{{ pos.col or loop.index }}"
             data-sizex="{{ pos.size_x or 4 }}"
             data-sizey="{{ pos.size_y or 4 }}">
-            
+
             <div class="chart-header">
               <div class="row">
                 <div class="col-md-12 text-center header">
@@ -124,9 +124,9 @@ <h2>
             </div>
             <div class="row chart-container">
               <input type="hidden" slice_id="{{ slice.id }}" value="false">
-              <div id="{{ viz.token }}" class="token col-md-12">
+              <div id="{{ slice.token }}" class="token col-md-12">
                 <img src="{{ url_for("static", filename="assets/images/loading.gif") }}" class="loading" alt="loading">
-                <div class="slice_container" id="{{ viz.token }}_con"></div>
+                <div class="slice_container" id="{{ slice.token }}_con"></div>
               </div>
             </div>
           </li>
diff --git a/caravel/views.py b/caravel/views.py
index 8c96be962c71a..d58473921a29b 100644
--- a/caravel/views.py
+++ b/caravel/views.py
@@ -633,7 +633,6 @@ def dashboard(self, dashboard_id):
             qry = qry.filter_by(slug=dashboard_id)
 
         templates = session.query(models.CssTemplate).all()
-
         dash = qry.first()
 
         # Hack to log the dashboard_id properly, even when getting a slug
diff --git a/caravel/viz.py b/caravel/viz.py
index e5cbcc49f334c..305c9d9ac1ff4 100644
--- a/caravel/viz.py
+++ b/caravel/viz.py
@@ -43,6 +43,8 @@ class BaseViz(object):
 
     def __init__(self, datasource, form_data, slice=None):
         self.orig_form_data = form_data
+        if not datasource:
+            raise Exception("Viz is missing a datasource")
         self.datasource = datasource
         self.request = request
         self.viz_type = form_data.get("viz_type")