CephFS Helpers

Added a helper function to test if ceph fs new has already
been called.  If it has been than the ceph_broker will
skip calling it again.

Change-Id: Ib39542a55db5f03f08af72054c14bd6abb3d6a2a

ceph/__init__.py

@@ -1244,6 +1244,37 @@ def get_running_osds():
         return []
 
 
+def get_cephfs(service):
+    """
+    List the Ceph Filesystems that exist
+    :rtype : list.  Returns a list of the ceph filesystems
+    :param service:  The service name to run the ceph command under
+    """
+    if get_version() < 0.86:
+        # This command wasn't introduced until 0.86 ceph
+        return []
+    try:
+        output = subprocess.check_output(["ceph",
+                                          '--id', service,
+                                          "fs", "ls"])
+        if not output:
+            return []
+        """
+        Example subprocess output:
+        'name: ip-172-31-23-165, metadata pool: ip-172-31-23-165_metadata,
+         data pools: [ip-172-31-23-165_data ]\n'
+        output: filesystems: ['ip-172-31-23-165']
+        """
+        filesystems = []
+        for line in output.splitlines():
+            parts = line.split(',')
+            for part in parts:
+                if "name" in part:
+                    filesystems.append(part.split(' ')[1])
+    except subprocess.CalledProcessError:
+        return []
+
+
 def wait_for_all_monitors_to_upgrade(new_version, upgrade_key):
     """
     Fairly self explanatory name.  This function will wait

ceph/ceph_broker.py

@@ -24,6 +24,7 @@ from charmhelpers.core.hookenv import (
     INFO,
     ERROR,
 )
+from ceph import get_cephfs
 from charmhelpers.contrib.storage.linux.ceph import (
     create_erasure_profile,
     delete_pool,
@@ -418,7 +419,12 @@ def handle_create_cephfs(request, service):
         log(msg, level=ERROR)
         return {'exit-code': 1, 'stderr': msg}
 
-    # Finally create CephFS
+    if get_cephfs(service=service):
+        # CephFS new has already been called
+        log("CephFS already created")
+        return
+
+        # Finally create CephFS
     try:
         check_output(["ceph",
                       '--id', service,
@@ -426,8 +432,12 @@ def handle_create_cephfs(request, service):
                       metadata_pool,
                       data_pool])
     except CalledProcessError as err:
-        log(err.output, level=ERROR)
-        return {'exit-code': 1, 'stderr': err.output}
+        if err.returncode == 22:
+            log("CephFS already created")
+            return
+        else:
+            log(err.output, level=ERROR)
+            return {'exit-code': 1, 'stderr': err.output}
 
 
 def handle_rgw_region_set(request, service):

unit_tests/test_ceph_broker.py

@@ -112,13 +112,16 @@ class CephBrokerTestCase(unittest.TestCase):
         self.assertEqual(json.loads(rc)['exit-code'], 0)
         self.assertEqual(json.loads(rc)['request-id'], '1ef5aede')
 
+    @mock.patch('ceph_broker.get_cephfs')
     @mock.patch('ceph_broker.check_output')
     @mock.patch('ceph_broker.pool_exists')
     @mock.patch('ceph_broker.log')
     def test_process_requests_create_cephfs(self,
                                             mock_log,
                                             mock_pool_exists,
-                                            check_output):
+                                            check_output,
+                                            get_cephfs):
+        get_cephfs.return_value = []
         mock_pool_exists.return_value = True
         reqs = json.dumps({'api-version': 1,
                            'request-id': '1ef5aede',