forms: make csv import parse dates accepts a list of columns (#4639)

Instead of a boolean which has way less chances to work. While
at it add a proper label for the "con" field.

Fixes #4637

superset/forms.py

@@ -10,7 +10,7 @@ from flask_appbuilder.forms import DynamicForm
 from flask_babel import lazy_gettext as _
 from flask_wtf.file import FileAllowed, FileField, FileRequired
 from wtforms import (
-    BooleanField, IntegerField, SelectField, StringField)
+    BooleanField, Field, IntegerField, SelectField, StringField)
 from wtforms.ext.sqlalchemy.fields import QuerySelectField
 from wtforms.validators import DataRequired, NumberRange, Optional
 
@@ -20,6 +20,32 @@ from superset.models import core as models
 config = app.config
 
 
+class CommaSeparatedListField(Field):
+    widget = BS3TextFieldWidget()
+
+    def _value(self):
+        if self.data:
+            return u', '.join(self.data)
+        else:
+            return u''
+
+    def process_formdata(self, valuelist):
+        if valuelist:
+            self.data = [x.strip() for x in valuelist[0].split(',')]
+        else:
+            self.data = []
+
+
+def filter_not_empty_values(value):
+    """Returns a list of non empty values or None"""
+    if not value:
+        return None
+    data = [x for x in value if x]
+    if not data:
+        return None
+    return data
+
+
 class CsvToDatabaseForm(DynamicForm):
     # pylint: disable=E0211
     def all_db_items():
@@ -36,6 +62,7 @@ class CsvToDatabaseForm(DynamicForm):
         validators=[
             FileRequired(), FileAllowed(['csv'], _('CSV Files Only!'))])
     con = QuerySelectField(
+        _('Database'),
         query_factory=all_db_items,
         get_pk=lambda a: a.id, get_label=lambda a: a.database_name)
     sep = StringField(
@@ -99,9 +126,12 @@ class CsvToDatabaseForm(DynamicForm):
         description=_(
             'Skip blank lines rather than interpreting them '
             'as NaN values.'))
-    parse_dates = BooleanField(
+    parse_dates = CommaSeparatedListField(
         _('Parse Dates'),
-        description=_('Parse date values.'))
+        description=_(
+            'A comma separated list of columns that should be '
+            'parsed as dates.'),
+        filters=[filter_not_empty_values])
     infer_datetime_format = BooleanField(
         _('Infer Datetime Format'),
         description=_(

superset/views/core.py

@@ -339,7 +339,6 @@ class CsvToDatabaseView(SimpleFormView):
         form.mangle_dupe_cols.data = True
         form.skipinitialspace.data = False
         form.skip_blank_lines.data = True
-        form.parse_dates.data = True
         form.infer_datetime_format.data = True
         form.decimal.data = '.'
         form.if_exists.data = 'append'

tests/form_tests.py

@@ -0,0 +1,28 @@
+# -*- coding: utf-8 -*-
+from __future__ import absolute_import
+from __future__ import division
+from __future__ import print_function
+from __future__ import unicode_literals
+
+from tests.base_tests import SupersetTestCase
+from wtforms.form import Form
+
+from superset.forms import (
+    CommaSeparatedListField, filter_not_empty_values)
+
+
+class FormTestCase(SupersetTestCase):
+
+    def test_comma_separated_list_field(self):
+        field = CommaSeparatedListField().bind(Form(), 'foo')
+        field.process_formdata([u''])
+        self.assertEqual(field.data, [u''])
+
+        field.process_formdata(['a,comma,separated,list'])
+        self.assertEqual(field.data, [u'a', u'comma', u'separated', u'list'])
+
+    def test_filter_not_empty_values(self):
+        self.assertEqual(filter_not_empty_values(None), None)
+        self.assertEqual(filter_not_empty_values([]), None)
+        self.assertEqual(filter_not_empty_values(['']), None)
+        self.assertEqual(filter_not_empty_values(['hi']), ['hi'])