Update OSD replacement functionality

1. Simplify this by leveraging the existing remove_osd/add_osd
functions, since its task was functionally identical to those two in
sequential order.
2. Add support for split OSDs within the command (replacing all OSDs on
the block device(s) as required).
3. Add additional configurability and flexibility around the old device,
weight, and external DB LVs.

daemon-common/ceph.py

@@ -26,6 +26,7 @@ import time
 import math
 
 from concurrent.futures import ThreadPoolExecutor
+from distutils.util import strtobool
 
 import daemon_lib.vm as vm
 import daemon_lib.common as common
@@ -211,7 +212,7 @@ def getOSDInformation(zkhandler, osd_id):
     # Get the devices
     osd_node = zkhandler.read(("osd.node", osd_id))
     osd_device = zkhandler.read(("osd.device", osd_id))
-    osd_is_split = zkhandler.read(("osd.is_split", osd_id))
+    osd_is_split = bool(strtobool(zkhandler.read(("osd.is_split", osd_id))))
     osd_db_device = zkhandler.read(("osd.db_device", osd_id))
     # Parse the stats data
     osd_stats_raw = zkhandler.read(("osd.stats", osd_id))
@@ -329,12 +330,18 @@ def add_osd(
     return success, message
 
 
-def replace_osd(zkhandler, osd_id, new_device, weight):
+def replace_osd(
+    zkhandler,
+    osd_id,
+    new_device,
+    old_device=None,
+    weight=None,
+    ext_db_ratio=None,
+    ext_db_size=None,
+):
     # Get current OSD information
     osd_information = getOSDInformation(zkhandler, osd_id)
     node = osd_information["node"]
-    old_device = osd_information["device"]
-    ext_db_flag = True if osd_information["db_device"] else False
 
     # Verify target block device isn't in use
     block_osd = verifyOSDBlock(zkhandler, node, new_device)
@@ -347,8 +354,8 @@ def replace_osd(zkhandler, osd_id, new_device, weight):
         )
 
     # Tell the cluster to create a new OSD for the host
-    replace_osd_string = "osd_replace {},{},{},{},{},{}".format(
-        node, osd_id, old_device, new_device, weight, ext_db_flag
+    replace_osd_string = "osd_replace {},{},{},{},{},{},{}".format(
+        node, osd_id, new_device, old_device, weight, ext_db_ratio, ext_db_size
     )
     zkhandler.write([("base.cmd.ceph", replace_osd_string)])
     # Wait 1/2 second for the cluster to get the message and start working