Integrating textfsm support directly into Netmiko

netmiko/base_connection.py

@@ -21,7 +21,7 @@
 
 from netmiko.netmiko_globals import MAX_BUFFER, BACKSPACE_CHAR
 from netmiko.ssh_exception import NetMikoTimeoutException, NetMikoAuthenticationException
-from netmiko.utilities import write_bytes, check_serial_port
+from netmiko.utilities import write_bytes, check_serial_port, get_structured_data
 from netmiko.py23_compat import string_types
 from netmiko import log
 import serial
@@ -869,7 +869,8 @@ def strip_prompt(self, a_string):
 
     def send_command(self, command_string, expect_string=None,
                      delay_factor=1, max_loops=500, auto_find_prompt=True,
-                     strip_prompt=True, strip_command=True, normalize=True):
+                     strip_prompt=True, strip_command=True, normalize=True,
+                     use_textfsm=False):
         """Execute command_string on the SSH channel using a pattern-based mechanism. Generally
         used for show commands. By default this method will keep waiting to receive data until the
         network device prompt is detected. The current network device prompt will be determined
@@ -897,6 +898,9 @@ def send_command(self, command_string, expect_string=None,
 
         :param normalize: Ensure the proper enter is sent at end of command (default: True).
         :type normalize: bool
+
+        :param use_textfsm: Process command output through TextFSM template (default: False).
+        :type normalize: bool
         """
         # Time to delay in each read loop
         loop_delay = .2
@@ -958,6 +962,9 @@ def send_command(self, command_string, expect_string=None,
 
         output = self._sanitize_output(output, strip_command=strip_command,
                                        command_string=command_string, strip_prompt=strip_prompt)
+        if use_textfsm:
+            output = get_structured_data(output, platform=self.device_type,
+                                         command=command_string.strip())
         return output
 
     def send_command_expect(self, *args, **kwargs):

netmiko/utilities.py

@@ -6,6 +6,9 @@
 import io
 import os
 import serial.tools.list_ports
+import clitable
+from clitable import CliTableError
+
 
 # Dictionary mapping 'show run' for vendors with different command
 SHOW_RUN_MAPPER = {
@@ -175,3 +178,53 @@ def check_serial_port(name):
         for p in ports:
             msg += "{},".format(str(p))
         raise ValueError(msg)
+
+
+def get_template_dir():
+    """Find and return the ntc-templates/templates dir."""
+    try:
+        template_dir = os.environ['NET_TEXTFSM']
+        index = os.path.join(template_dir, 'index')
+        if not os.path.isfile(index):
+            # Assume only base ./ntc-templates specified
+            template_dir = os.path.join(template_dir, 'templates')
+    except KeyError:
+        # Construct path ~/ntc-templates/templates
+        home_dir = os.path.expanduser("~")
+        template_dir = os.path.join(home_dir, 'ntc-templates', 'templates')
+
+    index = os.path.join(template_dir, 'index')
+    if not os.path.isdir(template_dir) or not os.path.isfile(index):
+        msg = """
+Valid ntc-templates not found, please install https://github.com/networktocode/ntc-templates
+and then set the NET_TEXTFSM environment variable to point to the ./ntc-templates/templates
+directory."""
+        raise ValueError(msg)
+    return template_dir
+
+
+def clitable_to_dict(cli_table):
+    """Converts TextFSM cli_table object to list of dictionaries."""
+    objs = []
+    for row in cli_table:
+        temp_dict = {}
+        for index, element in enumerate(row):
+            temp_dict[cli_table.header[index].lower()] = element
+        objs.append(temp_dict)
+    return objs
+
+
+def get_structured_data(raw_output, platform, command):
+    """Convert raw CLI output to structured data using TextFSM template."""
+    template_dir = get_template_dir()
+    index_file = os.path.join(template_dir, 'index')
+    textfsm_obj = clitable.CliTable(index_file, template_dir)
+    attrs = {'Command': command, 'Platform': platform}
+    try:
+        # Parse output through template
+        textfsm_obj.ParseCmd(raw_output, attrs)
+        structured_data = clitable_to_dict(textfsm_obj)
+        output = raw_output if structured_data == [] else structured_data
+        return output
+    except CliTableError:
+        return raw_output

requirements.txt

@@ -2,3 +2,4 @@ paramiko>=2.0.0
 scp>=0.10.0
 pyyaml
 pyserial
+textfsm

setup.py

@@ -40,7 +40,7 @@ def find_version(*file_paths):
         'Programming Language :: Python :: 3.6',
     ],
     packages=find_packages(exclude=("test*", )),
-    install_requires=['paramiko>=2.0.0', 'scp>=0.10.0', 'pyyaml', 'pyserial'],
+    install_requires=['paramiko>=2.0.0', 'scp>=0.10.0', 'pyyaml', 'pyserial', 'textfsm'],
     extras_require={
         'test': ['pytest>=3.2.5', ]
     },