extras/cliutils: Utils for creating CLI tools for Gluster

Refer README.md for documentation.

BUG: 1342356
Change-Id: Ic88504177137136bbb4b8b2c304ecc4af9bcfe30
Signed-off-by: Aravinda VK <avishwan@redhat.com>
Reviewed-on: http://review.gluster.org/14627
Reviewed-by: Prashanth Pai <ppai@redhat.com>
Reviewed-by: Niels de Vos <ndevos@redhat.com>
Smoke: Gluster Build System <jenkins@build.gluster.org>
NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org>
CentOS-regression: Gluster Build System <jenkins@build.gluster.org>
Reviewed-by: Jeff Darcy <jdarcy@redhat.com>

1 files changed, 212 insertions, 0 deletions

diff --git a/extras/cliutils/cliutils.py b/extras/cliutils/cliutils.py
new file mode 100644
index 00000000000..4e035d7ff5c
--- /dev/null
+++ b/extras/cliutils/cliutils.py
@@ -0,0 +1,212 @@
+# -*- coding: utf-8 -*-
+from __future__ import print_function
+from argparse import ArgumentParser, RawDescriptionHelpFormatter
+import inspect
+import subprocess
+import os
+import xml.etree.cElementTree as etree
+import json
+import sys
+
+MY_UUID = None
+parser = ArgumentParser(formatter_class=RawDescriptionHelpFormatter,
+                        description=__doc__)
+subparsers = parser.add_subparsers(dest="mode")
+
+subcommands = {}
+cache_data = {}
+ParseError = etree.ParseError if hasattr(etree, 'ParseError') else SyntaxError
+
+
+class GlusterCmdException(Exception):
+    pass
+
+
+def get_node_uuid():
+    # Caches the Node UUID in global variable,
+    # Executes gluster system:: uuid get command only if
+    # calling this function for first time
+    global MY_UUID
+    if MY_UUID is not None:
+        return MY_UUID
+
+    cmd = ["gluster", "system::", "uuid", "get", "--xml"]
+    rc, out, err = execute(cmd)
+
+    if rc != 0:
+        return None
+
+    tree = etree.fromstring(out)
+    uuid_el = tree.find("uuidGenerate/uuid")
+    MY_UUID = uuid_el.text
+    return MY_UUID
+
+
+def yesno(flag):
+    return "Yes" if flag else "No"
+
+
+def oknotok(flag):
+    return "OK" if flag else "NOT OK"
+
+
+def output_error(message):
+    print (message, file=sys.stderr)
+    sys.exit(1)
+
+
+def node_output_ok(message=""):
+    # Prints Success JSON output and exits with returncode zero
+    out = {"ok": True, "nodeid": get_node_uuid(), "output": message}
+    print (json.dumps(out))
+    sys.exit(0)
+
+
+def node_output_notok(message):
+    # Prints Error JSON output and exits with returncode zero
+    out = {"ok": False, "nodeid": get_node_uuid(), "error": message}
+    print (json.dumps(out))
+    sys.exit(0)
+
+
+def execute(cmd):
+    p = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+    out, err = p.communicate()
+    return p.returncode, out, err
+
+
+def get_pool_list():
+    cmd = ["gluster", "--mode=script", "pool", "list", "--xml"]
+    rc, out, err = execute(cmd)
+    if rc != 0:
+        output_error("Failed to get Pool Info: {0}".format(err))
+
+    tree = etree.fromstring(out)
+
+    pool = []
+    try:
+        for p in tree.findall('peerStatus/peer'):
+            pool.append({"nodeid": p.find("uuid").text,
+                         "hostname": p.find("hostname").text,
+                         "connected": (True if p.find("connected").text == "1"
+                                       else False)})
+    except (ParseError, AttributeError, ValueError) as e:
+        output_error("Failed to parse Pool Info: {0}".format(e))
+
+    return pool
+
+
+class NodeOutput(object):
+    def __init__(self, **kwargs):
+        self.nodeid = kwargs.get("nodeid", "")
+        self.hostname = kwargs.get("hostname", "")
+        self.node_up = kwargs.get("node_up", False)
+        self.ok = kwargs.get("ok", False)
+        self.output = kwargs.get("output", "N/A")
+        self.error = kwargs.get("error", "N/A")
+
+
+def execute_in_peers(name, args=[]):
+    # Get the file name of Caller function, If the file name is peer_example.py
+    # then Gluster peer command will be gluster system:: execute example.py
+    # Command name is without peer_
+    frame = inspect.stack()[1]
+    module = inspect.getmodule(frame[0])
+    actual_file = module.__file__
+    # If file is symlink then find actual file
+    if os.path.islink(actual_file):
+        actual_file = os.readlink(actual_file)
+
+    # Get the name of file without peer_
+    cmd_name = os.path.basename(actual_file).replace("peer_", "")
+    cmd = ["gluster", "system::", "execute", cmd_name, name] + args
+    rc, out, err = execute(cmd)
+    if rc != 0:
+        raise GlusterCmdException((rc, out, err, " ".join(cmd)))
+
+    out = out.strip().splitlines()
+
+    # JSON decode each line and construct one object with node id as key
+    all_nodes_data = {}
+    for node_data in out:
+        data = json.loads(node_data)
+        all_nodes_data[data["nodeid"]] = {
+            "nodeid": data.get("nodeid"),
+            "ok": data.get("ok"),
+            "output": data.get("output", ""),
+            "error": data.get("error", "")}
+
+    # gluster pool list
+    pool_list = get_pool_list()
+
+    data_out = []
+    # Iterate pool_list and merge all_nodes_data collected above
+    # If a peer node is down then set node_up = False
+    for p in pool_list:
+        p_data = all_nodes_data.get(p.get("nodeid"), None)
+        row_data = NodeOutput(node_up=False,
+                              hostname=p.get("hostname"),
+                              nodeid=p.get("nodeid"),
+                              ok=False)
+
+        if p_data is not None:
+            # Node is UP
+            row_data.node_up = True
+            row_data.ok = p_data.get("ok")
+            row_data.output = p_data.get("output")
+            row_data.error = p_data.get("error")
+
+        data_out.append(row_data)
+
+    return data_out
+
+
+def sync_file_to_peers(fname):
+    # Copy file from current node to all peer nodes, fname
+    # is path after GLUSTERD_WORKDIR
+    cmd = ["gluster", "system::", "copy", "file", fname]
+    rc, out, err = execute(cmd)
+    if rc != 0:
+        raise GlusterCmdException((rc, out, err))
+
+
+class Cmd(object):
+    name = ""
+
+    def run(self, args):
+        # Must required method. Raise NotImplementedError if derived class
+        # not implemented this method
+        raise NotImplementedError("\"run(self, args)\" method is "
+                                  "not implemented by \"{0}\"".format(
+                                      self.__class__.__name__))
+
+
+def runcli():
+    # Get list of Classes derived from class "Cmd" and create
+    # a subcommand as specified in the Class name. Call the args
+    # method by passing subcommand parser, Derived class can add
+    # arguments to the subcommand parser.
+    for c in Cmd.__subclasses__():
+        cls = c()
+        if getattr(cls, "name", "") == "":
+            raise NotImplementedError("\"name\" is not added "
+                                      "to \"{0}\"".format(
+                                          cls.__class__.__name__))
+
+        p = subparsers.add_parser(cls.name)
+        args_func = getattr(cls, "args", None)
+        if args_func is not None:
+            args_func(p)
+
+        # A dict to save subcommands, key is name of the subcommand
+        subcommands[cls.name] = cls
+
+    # Get all parsed arguments
+    args = parser.parse_args()
+
+    # Get the subcommand to execute
+    cls = subcommands.get(args.mode, None)
+
+    # Run
+    if cls is not None:
+        cls.run(args)