Add option -n, --node to ssh and sftp commands

This commit add an option to ssh and sftp subcommands to allow specify the hostname of the node where you want to ssh, and provide a mean to override the `ssh_to` option in the configuration file.

elasticluster/main.py

@@ -168,9 +168,9 @@ def main(self):
         try:
             return self.params.func()
         except MultipleInvalid as ex:
-            print("Error parsing configuration files: %s" % str.join(', ', [str(e) for e in ex.errors]))
+            print("Multiple errors: %s" % str.join(', ', [str(e) for e in ex.errors]))
         except Invalid as ex:
-            print("Error parsing configuration files: %s" % ex)
+            print("Error: %s" % ex)
             print("Exiting.")
             sys.exit(1)
 

elasticluster/subcommands.py

@@ -20,6 +20,7 @@
 # stdlib imports
 from abc import ABCMeta, abstractmethod
 from fnmatch import fnmatch
+from voluptuous import Invalid
 import os
 import sys
 
@@ -495,7 +496,7 @@ def execute(self):
         """
         Lists all nodes within the specified cluster with certain
         information like id and ip.
-        """        
+        """
         configurator = Configurator.fromConfig(
             self.params.config, storage_path=self.params.storage,
             include_config_dirs=True)
@@ -568,6 +569,10 @@ def setup(self, subparsers):
         parser.add_argument('cluster', help='name of the cluster')
         parser.add_argument('-v', '--verbose', action='count', default=0,
                             help="Increase verbosity.")
+        parser.add_argument('-n', '--node', metavar='HOSTNAME', dest='ssh_to',
+                            help="Name of node you want to ssh to. By "
+                            "default, the first node of the `ssh_to` option "
+                            "group is used.")
         parser.add_argument('ssh_args', metavar='args', nargs='*',
                             help="Execute the following command on the remote "
                             "machine instead of opening an interactive shell.")
@@ -585,7 +590,15 @@ def execute(self):
                       (cluster_name, ex))
             return
 
-        frontend = cluster.get_frontend_node()
+        if self.params.ssh_to:
+            try:
+                nodes = dict((n.name,n) for n in cluster.get_all_nodes())
+                frontend = nodes[self.params.ssh_to]
+            except KeyError:
+                raise Invalid(
+                    "Hostname %s not found in cluster %s" % (self.params.ssh_to, cluster_name))
+        else:
+            frontend = cluster.get_frontend_node()
         try:
             # ensure we can connect to the host
             if not frontend.preferred_ip:
@@ -625,6 +638,10 @@ def setup(self, subparsers):
             description=self.__doc__)
         parser.set_defaults(func=self)
         parser.add_argument('cluster', help='name of the cluster')
+        parser.add_argument('-n', '--node', metavar='HOSTNAME', dest='ssh_to',
+                            help="Name of node you want to ssh to. By "
+                            "default, the first node of the `ssh_to` option "
+                            "group is used.")
         parser.add_argument('-v', '--verbose', action='count', default=0,
                             help="Increase verbosity.")
         parser.add_argument('sftp_args', metavar='args', nargs='*',
@@ -644,12 +661,15 @@ def execute(self):
                       (cluster_name, ex))
             return
 
-        try:
-            cluster.ssh_to = configurator.cluster_conf[cluster.extra['template']]['cluster'].get('ssh_to', cluster.ssh_to)
+        if self.params.ssh_to:
+            try:
+                nodes = dict((n.name,n) for n in cluster.get_all_nodes())
+                frontend = nodes[self.params.ssh_to]
+            except KeyError:
+                raise Invalid(
+                    "Hostname %s not found in cluster %s" % (self.params.ssh_to, cluster_name))
+        else:
             frontend = cluster.get_frontend_node()
-        except NodeNotFound, ex:
-            log.error("Unable to connect to the frontend node: %s" % str(ex))
-            sys.exit(1)
         host = frontend.connection_ip()
         username = frontend.image_user
         knownhostsfile = cluster.known_hosts_file if cluster.known_hosts_file \
@@ -676,7 +696,8 @@ def setup(self, subparsers):
         parser.add_argument('cluster', help='name of the cluster')
         parser.add_argument('-v', '--verbose', action='count', default=0,
                             help="Increase verbosity.")
-        parser.add_argument('-a', '--append', metavar='FILE', help='append configuration to file FILE')
+        parser.add_argument('-a', '--append', metavar='FILE',
+                            help='append configuration to file FILE')
 
     def execute(self):
         """