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NAME

Net::CLI::Interact - Toolkit for CLI Automation

PURPOSE

This module exists to support developers of applications and libraries which must interact with a command line interface.

SYNOPSIS

use Net::CLI::Interact;

my $s = Net::CLI::Interact->new({
   personality => 'cisco',
   transport   => 'Telnet',
   connect_options => { host => '192.0.2.1' },
});

# respond to a usename/password prompt
$s->macro('to_user_exec', {
    params => ['my_username', 'my_password'],
});

my $interfaces = $s->cmd('show ip interfaces brief');

$s->macro('to_priv_exec', {
    params => ['my_password'],
});
# matched prompt is updated automatically

# paged output is slurped into one response
$s->macro('show_run');
my $config = $s->last_response;

DESCRIPTION

Automating command line interface (CLI) interactions is not a new idea, but can be tricky to implement. This module aims to provide a simple and manageable interface to CLI interactions, supporting:

  • SSH, Telnet and Serial-Line connections

  • Unix and Windows support

  • Reuseable device command phrasebooks

If you're a new user, please read the Tutorial. There's also a Cookbook and a Phrasebook Listing. For a more complete worked example check out the Net::Appliance::Session distribution, for which this module was written.

INTERFACE

new( \%options )

Prepares a new session for you, but will not connect to any device. On Windows platforms, you must download the plink.exe program, and pass its location to the app parameter. Other options are:

personality => $name (required)

The family of device command phrasebooks to load. There is a built-in library within this module, or you can provide a search path to other libraries. See Net::CLI::Interact::Manual::Phrasebook for further details.

transport => $backend (required)

The name of the transport backend used for the session, which may be one of Telnet, SSH, or Serial.

connect_options => \%options

If the transport backend can take any options (for example the target hostname), then pass those options in this value as a hash ref. See the respective manual pages for each transport backend for further details.

log_at => $log_level

To make using the logger somewhat easier, you can pass this argument the name of a log level (such as debug, info, etc) and all logging in the library will be enabled at that level. Use debug to learn about how the library is working internally. See Net::CLI::Interact::Logger for a list of the valid level names.

timeout => $seconds

Configures a default timeout value, in seconds, for interaction with the remote device. The default is 10 seconds. You can also set timeout on a per-command or per-macro call (see below).

Note that this does not (currently) apply to the initial connection.

cmd( $command )

Execute a single command statement on the connected device, and consume output until there is a match with the current prompt. The statement is executed verbatim on the device, with a newline appended.

In scalar context the last_response is returned (see below). In list context the gathered response is returned as a list of lines. In both cases your local platform's newline character will end all lines.

macro( $name, \%options? )

Execute the commands contained within the named Macro, which must be loaded from a Phrasebook. Options to control the output, including variables for substitution into the Macro, are passed in the %options hash reference.

In scalar context the last_response is returned (see below). In list context the gathered response is returned as a list of lines. In both cases your local platform's newline character will end all lines.

last_response

Returns the gathered output after the most recent cmd or macro. In scalar context all data is returned. In list context the gathered response is returned as a list of lines. In both cases your local platform's newline character will end all lines.

transport

Returns the Transport backend which was loaded based on the transport option to new. See the Telnet, SSH, or Serial documentation for further details.

phrasebook

Returns the Phrasebook object which was loaded based on the personality option given to new. See Net::CLI::Interact::Phrasebook for further details.

set_phrasebook( \%options )

Allows you to (re-)configure the loaded phrasebook, perhaps changing the personality or library, or other properties. The %options Hash ref should be any parameters from the Phrasebook module, but at a minimum must include a personality.

set_default_contination( $macro_name )

Briefly, a Continuation handles the slurping of paged output from commands. See the Net::CLI::Interact::Phrasebook documentation for further details.

Pass in the name of a defined Contination (Macro) to enable paging handling as a default for all sent commands. This is an alternative to describing the Continuation format in each Macro.

To unset the default Continuation, call the clear_default_continuation method.

logger

This is the application's Logger object. A powerful logging subsystem is available to your application, built upon the Log::Dispatch distribution. You can enable logging of this module's processes at various levels, or add your own logging statements.

set_global_log_at( $level )

To make using the logger somewhat easier, you can pass this method the name of a log level (such as debug, info, etc) and all logging in the library will be enabled at that level. Use debug to learn about how the library is working internally. See Net::CLI::Interact::Logger for a list of the valid level names.

FUTHER READING

Prompt Matching

Whenever a command statement is issued, output is slurped until a matching prompt is seen in that output. Control of the Prompts is shared between the definitions in Net::CLI::Interact::Phrasebook dictionaries, and methods of the Net::CLI::Interact::Role::Prompt core component. See that module's documentation for further details.

Actions and ActionSets

All commands and macros are composed from their phrasebook definitions into Actions and ActionSets (iterable sequences of Actions). See those modules' documentation for further details, in case you wish to introspect their structures.

COMPOSITION

See the following for further interface details:

AUTHOR

Oliver Gorwits <oliver@cpan.org>

COPYRIGHT AND LICENSE

This software is copyright (c) 2017 by Oliver Gorwits.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.