Caravel no data returned exception

caravel/assets/javascripts/modules/caravel.js

@@ -272,9 +272,13 @@ var px = (function () {
         $('.query-and-save button').removeAttr('disabled');
         always(data);
       },
-      error: function (msg) {
+      error: function (error) {
+        var msg = error.responseText;
         token.find("img.loading").hide();
         var err = '<div class="alert alert-danger">' + msg + '</div>';
+        if (error.getResponseHeader("Caravel-Exception") === "NoResultsException") {
+          err = '<div class="alert-nodata">' + msg + '</div>';
+        }
         container.html(err);
         container.show();
         $('span.query').removeClass('disabled');

caravel/assets/visualizations/big_number.js

@@ -13,7 +13,7 @@ function bigNumberVis(slice) {
     d3.json(slice.jsonEndpoint(), function (error, payload) {
       //Define the percentage bounds that define color from red to green
       if (error !== null) {
-        slice.error(error.responseText);
+        slice.error(error);
         return '';
       }
       var fd = payload.form_data;

caravel/assets/visualizations/directed_force.js

@@ -16,7 +16,7 @@ function directedForceVis(slice) {
     d3.json(slice.jsonEndpoint(), function (error, json) {
 
       if (error !== null) {
-        slice.error(error.responseText);
+        slice.error(error);
         return '';
       }
       var links = json.data;

caravel/assets/visualizations/heatmap.js

@@ -23,7 +23,7 @@ function heatmapVis(slice) {
     d3.json(slice.jsonEndpoint(), function (error, payload) {
       var matrix = {};
       if (error) {
-        slice.error(error.responseText);
+        slice.error(error);
         return '';
       }
       var fd = payload.form_data;

caravel/assets/visualizations/sankey.js

@@ -36,7 +36,7 @@ function sankeyVis(slice) {
 
     d3.json(slice.jsonEndpoint(), function (error, json) {
       if (error !== null) {
-        slice.error(error.responseText);
+        slice.error(error);
         return '';
       }
       var links = json.data;

caravel/assets/visualizations/sunburst.js

@@ -54,7 +54,7 @@ function sunburstVis(slice) {
 
     d3.json(slice.jsonEndpoint(), function (error, rawData) {
       if (error !== null) {
-        slice.error(error.responseText);
+        slice.error(error);
         return '';
       }
 

caravel/assets/visualizations/word_cloud.js

@@ -8,7 +8,7 @@ function wordCloudChart(slice) {
   function refresh() {
     d3.json(slice.jsonEndpoint(), function (error, json) {
       if (error !== null) {
-        slice.error(error.responseText);
+        slice.error(error);
         return '';
       }
       var data = json.data;

caravel/assets/visualizations/world_map.js

@@ -17,7 +17,7 @@ function worldMapChart(slice) {
       var fd = json.form_data;
 
       if (error !== null) {
-        slice.error(error.responseText);
+        slice.error(error);
         return '';
       }
       var ext = d3.extent(json.data, function (d) {

caravel/models.py

@@ -576,7 +576,20 @@ def query(  # sqla
                 select_exprs += [timestamp_grain]
                 groupby_exprs += [timestamp_grain]
 
-            tf = '%Y-%m-%d %H:%M:%S.%f'
+            # UGLY: I guess correct way is to delegate on SQLAlchemy dialect
+            # UPDATE: Datetime depends on each dialect and I haven't found an easy way to manage
+            #         Maybe we can allow user to define its custome format at Database definition
+            def get_dtformat(type):
+                if type == 'SMALLDATETIME' or type == 'DATETIME':
+                    return '%Y-%m-%d %H:%M:%S'
+                if type == 'DATE':
+                    return '%Y-%m-%d'
+                if type == 'TIME':
+                    return '%H:%M:%S'
+                return '%Y-%m-%d %H:%M:%S.%f'
+
+            tf = get_dtformat(cols[granularity].type or 'DATE')
+
             time_filter = [
                 timestamp >= from_dttm.strftime(tf),
                 timestamp <= to_dttm.strftime(tf),

caravel/utils.py

@@ -224,3 +224,7 @@ def readfile(filepath):
     with open(filepath) as f:
         content = f.read()
     return content
+
+
+class NoResultsException(Exception):
+    pass

caravel/views.py

@@ -27,6 +27,7 @@
 from wtforms.validators import ValidationError
 
 from caravel import appbuilder, db, models, viz, utils, app, sm, ascii_art
+from caravel.utils import NoResultsException
 
 config = app.config
 log_this = models.Log.log_this
@@ -40,12 +41,12 @@ def validate_json(form, field):  # noqa
         raise ValidationError("json isn't valid")
 
 
-def generate_download_headers(extension):
+def generate_download_headers(extension, headers=None):
     filename = datetime.now().strftime("%Y%m%d_%H%M%S")
     content_disp = "attachment; filename={}.{}".format(filename, extension)
-    headers = {
-        "Content-Disposition": content_disp,
-    }
+    if headers is None:
+        headers = {}
+    headers["Content-Disposition"] = content_disp
     return headers
 
 
@@ -481,18 +482,24 @@ def explore(self, datasource_type, datasource_id):
             slice=slc)
         if request.args.get("json") == "true":
             status = 200
+            headers = {}
             try:
                 payload = obj.get_json()
             except Exception as e:
+                t = type(e)
+                headers["Caravel-Exception"] = t.__name__
                 logging.exception(e)
-                if config.get("DEBUG"):
-                    raise e
-                payload = str(e)
+                if t is NoResultsException:
+                    payload = "No results"
+                else:
+                    if config.get("DEBUG"):
+                        raise e
+                    payload = str(e)
                 status = 500
             resp = Response(
                 payload,
                 status=status,
-                headers=generate_download_headers("json"),
+                headers=generate_download_headers("json", headers),
                 mimetype="application/json")
             return resp
         elif request.args.get("csv") == "true":

caravel/viz.py

@@ -26,6 +26,9 @@
 from caravel import app, utils, cache
 from caravel.forms import FormFactory
 
+
+from caravel.utils import NoResultsException
+
 config = app.config
 
 
@@ -139,8 +142,10 @@ def get_df(self, query_obj=None):
         self.results = self.datasource.query(**query_obj)
         self.query = self.results.query
         df = self.results.df
-        if df is None or df.empty:
-            raise Exception("No data, review your incantations!")
+        if df is None:
+            raise Exception("Error retrieving data")
+        elif df.empty:
+            raise NoResultsException()
         else:
             if 'timestamp' in df.columns:
                 df.timestamp = pd.to_datetime(df.timestamp, utc=False)

tests/core_tests.py

@@ -3,6 +3,7 @@
 import os
 import unittest
 
+import sys
 from flask import escape
 
 import caravel
@@ -58,7 +59,10 @@ def test_slices(self):
                 slc.viz.json_endpoint,
             ]
         for url in urls:
-            self.client.get(url)
+            try:
+                self.client.get(url)
+            except Exception:
+                raise ValueError(url, None, sys.exc_info()[2])
 
     def test_csv(self):
         self.client.get('/caravel/explore/table/1/?viz_type=table&granularity=ds&since=100+years&until=now&metrics=count&groupby=name&limit=50&show_brush=y&show_brush=false&show_legend=y&show_brush=false&rich_tooltip=y&show_brush=false&show_brush=false&show_brush=false&show_brush=false&y_axis_format=&x_axis_showminmax=y&show_brush=false&line_interpolation=linear&rolling_type=None&rolling_periods=&time_compare=&num_period_compare=&where=&having=&flt_col_0=gender&flt_op_0=in&flt_eq_0=&flt_col_0=gender&flt_op_0=in&flt_eq_0=&slice_id=14&slice_name=Boys&collapsed_fieldsets=&action=&datasource_name=birth_names&datasource_id=1&datasource_type=table&previous_viz_type=line&csv=true')