From 04d769ff249e8c9e616133dc17639088438667cb Mon Sep 17 00:00:00 2001
From: Maxime Beauchemin <maximebeauchemin@gmail.com>
Date: Fri, 15 Apr 2016 15:00:49 -0700
Subject: [PATCH] Some more error handling when rendering the explore view
 (#361)

---
 caravel/forms.py |  4 +++-
 caravel/views.py | 12 ++++++++----
 2 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/caravel/forms.py b/caravel/forms.py
index ec8d65d1074c6..0094ef4e67834 100644
--- a/caravel/forms.py
+++ b/caravel/forms.py
@@ -112,11 +112,13 @@ def __init__(self, viz):
         from caravel.viz import viz_types
         viz = self.viz
         datasource = viz.datasource
+        if not datasource.metrics_combo:
+            raise Exception("Please define at least one metric for your table")
         default_metric = datasource.metrics_combo[0][0]
 
         gb_cols = datasource.groupby_column_names
         default_groupby = gb_cols[0] if gb_cols else None
-        group_by_choices = [(s, s) for s in datasource.groupby_column_names]
+        group_by_choices = self.choicify(gb_cols)
         # Pool of all the fields that can be used in Caravel
         self.field_dict = {
             'viz_type': SelectField(
diff --git a/caravel/views.py b/caravel/views.py
index b8d745bd283bf..b34d1e2507b2b 100644
--- a/caravel/views.py
+++ b/caravel/views.py
@@ -490,10 +490,14 @@ def explore(self, datasource_type, datasource_id):
             return redirect(datasource.default_endpoint)
         if not viz_type:
             viz_type = "table"
-        obj = viz.viz_types[viz_type](
-            datasource,
-            form_data=request.args,
-            slice_=slc)
+        try:
+            obj = viz.viz_types[viz_type](
+                datasource,
+                form_data=request.args,
+                slice_=slc)
+        except Exception as e:
+            flash(str(e), "danger")
+            return redirect(error_redirect)
         if request.args.get("json") == "true":
             status = 200
             try: