StorPool: Raise on spopenstack, SP_OURID issues

The module 'spopenstack' is required for this connector, but is
installed as needed. Detecting early on if it is missing makes debugging
faster.

The same is true for the "SP_OURID" configuration item in
`_attach.config()`.

Change-Id: I6030d433dcf45f496bfee79aa00b2af9b51fd420

os_brick/initiator/connectors/storpool.py

@@ -59,14 +59,19 @@ def __init__(self, root_helper, driver=None,
             raise exception.BrickException(
                 'Could not import the StorPool API bindings')
 
-        if spopenstack is not None:
-            try:
-                self._attach = spopenstack.AttachDB(log=LOG)
-            except Exception as e:
-                raise exception.BrickException(
-                    'Could not initialize the StorPool API bindings: %s' % (e))
-        else:
-            self._attach = None
+        if spopenstack is None:
+            raise exception.BrickException(
+                'Could not import the required module "storpool.spopenstack"')
+
+        try:
+            self._attach = spopenstack.AttachDB(log=LOG)
+        except Exception as e:
+            raise exception.BrickException(
+                'Could not initialize the StorPool API bindings: %s' % (e))
+
+        if "SP_OURID" not in self._attach.config():
+            raise exception.BrickException(
+                'Could not read "SP_OURID" from the StorPool configuration"')
 
     def _detach_retry(self, sp_ourid, volume):
         """Retry detaching.

os_brick/tests/initiator/connectors/test_storpool.py

@@ -110,6 +110,16 @@ def setUp(self):
             None, execute=self.execute)
         self.adb = self.connector._attach
 
+    def test_raise_if_spopenstack_missing(self):
+        with mock.patch.object(connector, 'spopenstack', None):
+            self.assertRaises(exception.BrickException,
+                              connector.StorPoolConnector, "")
+
+    def test_raise_if_sp_ourid_missing(self):
+        with mock.patch.object(spopenstack.AttachDB, 'config', lambda x: {}):
+            self.assertRaises(exception.BrickException,
+                              connector.StorPoolConnector, "")
+
     def test_connect_volume(self):
         volume_name = volumeNameExt(self.fakeProp['volume'])
         api = mock.MagicMock(spec=['volumesReassignWait', 'volumeInfo'])