Fix #87 by working around non-federated sqlproxy connections (#89)

When Cross Database Joins were introduced in 10 all connections became "federated" by default, even if they weren't actually joined to anything else. 

In the file format that means they get represented as named-connection/connection elements. Expressed under one top-level connection element with a class of 'federated'.

Except for 'sqlproxy' connections (Published Data Sources) -- they stay in the old connection style as a top level connection element.

We need to, when in a 10.0 or greater workbook, get all federated connections (named-connection) plus go back and find any sqlproxy connections as well.

Author: t8y8

tableaudocumentapi/datasource.py

@@ -101,7 +101,9 @@ def __init__(self, datasource_xml, version):
         self._dsversion = version
 
     def _extract_federated_connections(self):
-        return list(map(Connection, self._dsxml.findall('.//named-connections/named-connection/*')))
+        connections = list(map(Connection, self._dsxml.findall('.//named-connections/named-connection/*')))
+        connections.extend(map(Connection, self._dsxml.findall("./connection[@class='sqlproxy']")))
+        return connections
 
     def _extract_legacy_connection(self):
         return list(map(Connection, self._dsxml.findall('connection')))

test/assets/multiple_connections.twb

@@ -0,0 +1,35 @@
+<?xml version='1.0' encoding='utf-8' ?>
+
+<!-- build main.16.0928.1300                                -->
+<workbook source-build='0.0.0 (0000.16.0928.1300)' source-platform='mac' version='10.1' xmlns:user='http://www.tableausoftware.com/xml/user'>
+  <datasources>
+    <datasource caption='xy (TestV1)' inline='true' name='sqlproxy.0uczajf02b02kv16u6atd08pslj5' version='10.1'>
+      <repository-location id='xyTestV1' path='/datasources' revision='1.0' />
+      <connection channel='http' class='sqlproxy' dbname='xyTestV1' directory='/dataserver' port='80' server='awesomeserver' username=''>
+        <relation name='sqlproxy' table='[sqlproxy]' type='table' />
+      </connection>
+    </datasource>
+    <datasource caption='xy+ (Multiple Connections)' inline='true' name='federated.1bw8gel1hkm5ms1c8jgrm0zixmde' version='10.1'>
+      <connection class='federated'>
+        <named-connections>
+          <named-connection caption='mysql55' name='mysql.0unbi0i1tfh602155zoou04tacme'>
+            <connection class='mysql' dbname='testv1' odbc-native-protocol='' port='' server='mysql55' source-charset='' username='test' />
+          </named-connection>
+          <named-connection caption='mssql2012.test' name='sqlserver.15j0kvj16xdjas1bs191w1ji441w'>
+            <connection authentication='sqlserver' class='sqlserver' dbname='TestV1' odbc-native-protocol='yes' one-time-sql='' server='mssql2012' username='test' />
+          </named-connection>
+        </named-connections>
+        <relation join='inner' type='join'>
+          <clause type='join'>
+            <expression op='='>
+              <expression op='[xy].[a]' />
+              <expression op='[xy1].[a]' />
+            </expression>
+          </clause>
+          <relation connection='mysql.0unbi0i1tfh602155zoou04tacme' name='xy' table='[xy]' type='table' />
+          <relation connection='sqlserver.15j0kvj16xdjas1bs191w1ji441w' name='xy1' table='[dbo].[xy]' type='table' />
+        </relation>
+      </connection>
+    </datasource>
+  </datasources>
+</workbook>

test/bvt.py

@@ -27,6 +27,9 @@
 
 EMPTY_WORKBOOK = os.path.join(TEST_DIR, 'assets', 'empty_workbook.twb')
 
+MULTI_CONNECTION_10 = os.path.join(
+    TEST_DIR, 'assets', 'multiple_connections.twb')
+
 
 class ConnectionParserTests(unittest.TestCase):
 
@@ -94,6 +97,26 @@ def test_can_create_datasource_from_connections(self):
         self.assertEqual(ds.connections[1].server, '1')
 
 
+class ConnectionParserInComplicatedWorkbooks(unittest.TestCase):
+
+    def setUp(self):
+        with open(MULTI_CONNECTION_10, 'rb') as in_file, open('test.twb', 'wb') as out_file:
+            out_file.write(in_file.read())
+            self.twb_file = out_file
+
+    def tearDown(self):
+        self.twb_file.close()
+        os.unlink(self.twb_file.name)
+
+    def test_can_mixed_connections_workbook(self):
+        wb = Workbook(self.twb_file.name)
+        self.assertTrue(len(wb.datasources), 2)
+        self.assertTrue(len(wb.datasources[1].connections), 2)
+        self.assertEqual(wb.datasources[0].connections[0].dbclass, 'sqlproxy')
+        self.assertEqual(wb.datasources[1].connections[0].dbclass, 'mysql')
+        self.assertEqual(wb.datasources[1].connections[1].dbclass, 'sqlserver')
+
+
 class DatasourceModelTests(unittest.TestCase):
 
     def setUp(self):