Refactor 'heketi_node_list' function

Do following improvements to this function:
- Remove support of python Heketi client, because it is dead code.
  It is dead code, because all of the tests which use this function,
  explicitly depend on the CLI output, not being compatible with it.
- Remove useless 'json' arg, as CLI client does not support it for 'node
  list' command.
- Parse list of node IDs in it, not delegating this to the consumer.
- Raise exception in case we failed to get list of nodes

And, of course, update all the places where this function is used.
Making those places use less code compared to previous variant.

Change-Id: I3f1ffe6082541e63dc3d638c19c54086aa12580f

1 files changed, 26 insertions, 42 deletions

diff --git a/cns-libs/cnslibs/common/heketi_ops.py b/cns-libs/cnslibs/common/heketi_ops.py
index 8e36d331..fd6c4b34 100644
--- a/cns-libs/cnslibs/common/heketi_ops.py
+++ b/cns-libs/cnslibs/common/heketi_ops.py
@@ -13,6 +13,7 @@ try:
 except:
     g.log.error("Please install python-client for heketi and re-run the test")
 
+from cnslibs.common import exceptions
 
 HEKETI_SSH_KEY = "/etc/heketi/heketi_key"
 HEKETI_CONFIG_FILE = "/etc/heketi/heketi.json"
@@ -1839,54 +1840,37 @@ def heketi_node_remove(heketi_client_node, heketi_server_url, node_id,
         return node
 
 
-def heketi_node_list(heketi_client_node, heketi_server_url, mode='cli',
-                     **kwargs):
-    """Executes heketi node info command.
+def heketi_node_list(heketi_client_node, heketi_server_url,
+                     heketi_user=None, heketi_secret=None):
+    """Execute CLI 'heketi node list' command and parse its output.
 
     Args:
-        heketi_client_node (str): Node on which cmd has to be executed.
-        heketi_server_url (str): Heketi server url
-
-    Kwargs:
-        mode (str): Mode to excecute the command.
-            It can be cli|url. Defaults to cli.
-        **kwargs
-            The keys, values in kwargs are:
-                - json : (bool)
-                - secret : (str)|None
-                - user : (str)|None
-
+        heketi_client_node (str): Node on which cmd has to be executed
+        heketi_server_url (str): Heketi server url to perform request to
+        heketi_user (str): Name of the user to perform request with
+        heketi_secret (str): Secret for 'heketi_user'
     Returns:
-        dict: node list on success, if mode='cli' without json, then it
-            returns raw output in string format.
-        False: in case of failure
-
-    Example:
-        heketi_node_list(heketi_client_node, heketi_server_url)
+        list of strings which are node IDs
+    Raises: cnslibs.common.exceptions.ExecutionError in case CLI command failed.
     """
 
-    (heketi_server_url,
-     json_arg, admin_key, user) = _set_heketi_global_flags(heketi_server_url,
-                                                           **kwargs)
-    if mode == 'cli':
-        cmd = ("heketi-cli -s %s node list %s %s %s"
-               % (heketi_server_url, json_arg, admin_key, user))
-        ret, out, _ = g.run(heketi_client_node, cmd)
-        if ret != 0:
-            g.log.error("Failed to execute heketi-cli node list command")
-            return False
+    heketi_server_url, json_arg, admin_key, user = _set_heketi_global_flags(
+        heketi_server_url, user=heketi_user, secret=heketi_secret)
 
-        return out
-    else:
-        try:
-            user = user.split(' ')[-1] if user else 'admin'
-            admin_key = admin_key.split('t ')[-1] if admin_key else admin_key
-            conn = HeketiClient(heketi_server_url, user, admin_key)
-            node_list = conn.node_list()
-        except:
-            g.log.error("Failed to get node list using heketi")
-            return False
-        return node_list
+    cmd = ("heketi-cli -s %s node list %s %s %s"
+           % (heketi_server_url, json_arg, admin_key, user))
+    ret, out, _ = g.run(heketi_client_node, cmd)
+    if ret != 0:
+        msg = "Failed to get list of Heketi nodes."
+        g.log.error(msg)
+        raise exceptions.ExecutionError(msg)
+
+    heketi_node_id_list = []
+    for line in out.strip().split("\n"):
+        # Line looks like this: 'Id:nodeIdString\tCluster:clusterIdString'
+        heketi_node_id_list.append(
+            line.strip().split("Cluster")[0].strip().split(":")[1])
+    return heketi_node_id_list
 
 
 def heketi_blockvolume_info(heketi_client_node, heketi_server_url,