[spp] [PATCH 2/2] controller: add registering to server command

[ogawa.yasufumi@lab.ntt.co.jp]

From: Yasufumi Ogawa <ogawa.yasufumi@lab.ntt.co.jp>

All of REST API nodes should be specified while launching SPP CLI. To
add another one, SPP CLI should be terminated and restarted at once.

This update is to add registering and unregistering node to avoid this
inconvenience. Register with `add` or unregister with `del` command.

    # Register
    spp > server add 192.168.122.177
    Registered spp-ctl "192.168.122.177:7777".

    # Unregister
    spp > server del 2  # or 192.168.1.102
    Unregistered spp-ctl "192.168.1.102:7777".

Signed-off-by: Yasufumi Ogawa <ogawa.yasufumi@lab.ntt.co.jp>
---
 src/controller/commands/server.py | 219 ++++++++++++++++++++++++++++++++++----
 src/controller/shell.py           |  30 +++++-
 2 files changed, 223 insertions(+), 26 deletions(-)

diff --git a/src/controller/commands/server.py b/src/controller/commands/server.py
index ca362ab..eece1f6 100644
--- a/src/controller/commands/server.py
+++ b/src/controller/commands/server.py
@@ -2,7 +2,9 @@
 # Copyright(c) 2017-2018 Nippon Telegraph and Telephone Corporation
 
 import re
+from ..shell_lib import common
 from ..spp_common import logger
+from .. import spp_ctl_client
 
 
 class SppCtlServer(object):
@@ -11,15 +13,15 @@ class SppCtlServer(object):
     SppCtlServer class is intended to be used in Shell class as a delegator
     for running 'server' command.
 
-    'self.run()' is called from do_pri() and 'self.complete()' is called
-    from complete_pri() of both of which is defined in Shell.
+    'self.run()' is called from do_server() and 'self.complete()' is called
+    from complete_server() of both of which is defined in Shell.
     """
 
-    SERVER_CMDS = ['list']
+    SERVER_CMDS = ['list', 'add', 'del']
 
     def __init__(self, spp_cli_objs):
         self.spp_cli_objs = spp_cli_objs
-        self.current_idx = 0
+        self.current_idx = 0  # index of current server in use
 
     def run(self, commands):
         args = re.sub(r'\s+', ' ', commands).split(' ')
@@ -27,10 +29,26 @@ class SppCtlServer(object):
             args.remove('')
 
         if len(args) == 0 or args[0] == 'list':
-            self._show_list()
-        else:
+            self._show_server_list()
+
+        elif args[0] == 'add':
+            if len(args) < 2:
+                print('Error: server address is requiired.')
+            else:
+                self._register_server(args[1])
+
+        elif args[0] == 'del':
+            if len(args) < 2:
+                print('Error: server address or index is requiired.')
+            else:
+                self._unregister_server(args[1])
+
+        else:  # show servers if index is given.
             idx = int(args[0]) - 1
-            self._switch_to(idx)
+            if idx >= 0:
+                self._switch_to(idx)
+            else:
+                print('Server index should be > 0 !')
 
     def complete(self, text, line, begidx, endidx):
         """Completion for server command.
@@ -39,23 +57,54 @@ class SppCtlServer(object):
         """
 
         candidates = []
-        for i in range(len(self.spp_cli_objs)):
-            candidates.append(str(i))
-        candidates = candidates + self.SERVER_CMDS[:]
+        tokens = line.split(' ')
 
-        if not text:
-            completions = candidates
-        else:
-            completions = [p for p in candidates
-                           if p.startswith(text)
-                           ]
+        # Show sub commands and indices of servers.
+        if len(tokens) == 2:
+            # Add server IDs
+            for i in range(len(self.spp_cli_objs)):
+                candidates.append(str(i + 1))
+
+            # Add sub commands
+            candidates = candidates + self.SERVER_CMDS[:]
+
+            if not text:
+                completions = candidates
+            else:
+                completions = [p for p in candidates
+                               if p.startswith(text)
+                               ]
+
+        # Show args of `del` sub command.
+        elif len(tokens) == 3:
+            if tokens[1] == 'del':
+                for i in range(len(self.spp_cli_objs)):
+                    # Add both of indices and addresses to candidates.
+                    candidates.append(str(i + 1))
+                    candidates.append('{}:{}'.format(
+                        self.spp_cli_objs[i].ip_addr,
+                        self.spp_cli_objs[i].port))
+
+                # Remove current server from candidates.
+                if (str(self.current_idx + 1)) in candidates:
+                    candidates.remove(str(self.current_idx + 1))
+                    candidates.remove('{}:{}'.format(
+                            self.spp_cli_objs[self.current_idx].ip_addr,
+                            self.spp_cli_objs[self.current_idx].port))
+
+            if not text:
+                completions = candidates
+            else:
+                completions = [p for p in candidates
+                               if p.startswith(text)
+                               ]
 
         return completions
 
     def get_current_server(self):
         return self.spp_cli_objs[self.current_idx]
 
-    def _show_list(self):
+    def _show_server_list(self):
         cnt = 1
         for cli_obj in self.spp_cli_objs:
             # Put a mark to current server.
@@ -69,11 +118,139 @@ class SppCtlServer(object):
             cnt += 1
 
     def _switch_to(self, idx):
+        """Switch to server of given index."""
+
         if len(self.spp_cli_objs) > idx:
             self.current_idx = idx
             cli_obj = self.spp_cli_objs[self.current_idx]
-            print('Switch spp-ctl to "%d: %s:%d"' %
-                    (idx+1, cli_obj.ip_addr, cli_obj.port))
+            print('Switch spp-ctl to "{}: {}:{}".'.format(
+                 idx+1, cli_obj.ip_addr, cli_obj.port))
         else:
-            print('Index should be less than %d!' %
-                    (len(self.spp_cli_objs) + 1))
+            print('Cannot switch to no existing server "{}".'.format(
+                idx + 1))
+
+    def _parse_addr(self, addr):
+        """Parse IP address and port of `ipaddr:port` format.
+
+        Return IP address and port as a tuple of (ipaddr, port). This
+        is an example.
+            ipaddr, port = self._parse_addr('192.168.11.100:7777')
+        """
+        if ':' in addr:
+            ipaddr, port = addr.split(':')
+            if common.is_valid_port(port) is False:
+                print('Error: Invalid port in "{}".'.format(port))
+                port = None
+            else:
+                port = int(port)
+        else:
+            ipaddr = addr
+            port = 7777
+
+        if common.is_valid_ipv4_addr(ipaddr) is False:
+            print('Error: Invalid address "{}".'.format(ipaddr))
+            ipaddr = None
+
+        return ipaddr, port
+
+    def _is_address_registered(self, ipaddr, port):
+        """Check if given address is included server list."""
+
+        if (ipaddr is not None) and (port is not None):
+            for cli_obj in self.spp_cli_objs:
+                if (cli_obj.ip_addr == ipaddr) and \
+                        (cli_obj.port == int(port)):
+                    return True
+
+        return False
+
+    def _register_server(self, addr):
+        """Add server of given address to server list."""
+
+        ipaddr, port = self._parse_addr(addr)
+
+        if (ipaddr is None) or (port is None):
+            return None
+
+        if self._is_address_registered(ipaddr, port) is True:
+            print('"{}:{}" is already registered.'.format(
+                ipaddr, port))
+            return None
+
+        spp_ctl_cli = spp_ctl_client.SppCtlClient(ipaddr, port)
+        if spp_ctl_cli.is_server_running() is False:
+            print('Is not spp-ctl on "{}:{}", nor correct address?'.format(
+                  ipaddr, port))
+            return False
+        else:
+            self.spp_cli_objs.append(spp_ctl_cli)
+            print('Registered spp-ctl "{}:{}".'.format(ipaddr, port))
+
+        return True
+
+    def _unregister_server(self, arg):
+        """Delete server of given address from server list.
+
+        Server is specified with ID or address.
+        """
+
+        removed = None  # contains instance of removed SppCtlClient.
+
+        # Check if given ID is negative and remove `-` because this method
+        # uses `str.isdigit()`, but it cannot be used for negative number.
+        if arg.startswith('-'):
+            is_arg_negative = True
+            arg = arg[1:]
+        else:
+            is_arg_negative = False
+
+        # Specified with server ID.
+        if str.isdigit(arg):
+            if is_arg_negative:  # return to negative num.
+                idx = -1 * int(arg) - 1
+            else:
+                idx = int(arg) - 1
+
+            if idx < 0:  # negative ID is invalid
+                print('Cannot del server of invalid ID "{}"!'.format(
+                    idx + 1))
+            elif (idx > len(self.spp_cli_objs) - 1):
+                print('Cannot del server "{}" not exist!'.format(idx + 1))
+            elif idx == self.current_idx:
+                print('Cannot del server "{}" in use!'.format(
+                    self.current_idx + 1))
+            else:
+                removed = self.spp_cli_objs.pop(idx)
+
+        # Specified with address of the server.
+        else:
+            ipaddr, port = self._parse_addr(arg)
+            if (ipaddr is None) or (port is None):
+                return None
+
+            if self._is_address_registered(ipaddr, port) is False:
+                print('"{}:{}" is not registered.'.format(ipaddr, port))
+                return None
+
+            cur_serv = self.spp_cli_objs[self.current_idx]
+            if (ipaddr == cur_serv.ip_addr) and (port == cur_serv.port):
+                print('Cannot del server "{}:{}" in use!'.format(
+                    ipaddr, port))
+                return None
+
+            cnt = 0
+            for spp_cli in self.spp_cli_objs:
+                if (ipaddr == spp_cli.ip_addr) and (port == spp_cli.port):
+                    removed = self.spp_cli_objs.pop(cnt)
+                    break
+                cnt += 1
+
+        if removed is not None:
+            # Update current_idx if removed is before current in the order.
+            if self.current_idx >= len(self.spp_cli_objs):
+                self.current_idx = self.current_idx - 1
+
+            print('Unregistered spp-ctl "{}:{}".'.format(
+                removed.ip_addr, removed.port))
+
+        return True
diff --git a/src/controller/shell.py b/src/controller/shell.py
index 6ce4dca..6dc6514 100644
--- a/src/controller/shell.py
+++ b/src/controller/shell.py
@@ -260,12 +260,31 @@ class Shell(cmd.Cmd, object):
     def do_server(self, commands):
         """Switch SPP REST API server.
 
-        spp > server  # or 'server list'
-          1: 192.168.1.101:7777 *
-          2: 192.168.1.102:7777
+        Show a list of servers. '*' means that it is under the control.
 
-        spp > server 2
-        Switch spp-ctl to "2: 192.168.1.102:7777".
+            spp > server  # or 'server list'
+              1: 192.168.1.101:7777 *
+              2: 192.168.1.102:7777
+
+        Switch to the second node with index or address.
+
+            spp > server 2
+            Switch spp-ctl to "2: 192.168.1.102:7777".
+
+            # It is the same
+            spp > server 192.168.1.101  # no need port if default
+            Switch spp-ctl to "1: 192.168.1.101:7777".
+
+        Register or unregister a node by using 'add' or 'del' command.
+        For unregistering, node is also specified with index.
+
+            # Register third node
+            spp > server add 192.168.122.177
+            Registered spp-ctl "192.168.122.177:7777".
+
+            # Unregister second one
+            spp > server del 2  # or 192.168.1.102
+            Unregistered spp-ctl "192.168.1.102:7777".
         """
 
         self.spp_ctl_server.run(commands)
@@ -274,6 +293,7 @@ class Shell(cmd.Cmd, object):
     def complete_server(self, text, line, begidx, endidx):
         """Completion for server command."""
 
+        line = self.clean_cmd(line)
         res = self.spp_ctl_server.complete(text, line, begidx, endidx)
         return res
 
-- 
2.7.4