trigger.utils — CLI tools and utilities library

A collection of CLI tools and utilities used by Trigger.

class trigger.utils.JuniperElement(key, value)
key

Alias for field number 0

value

Alias for field number 1

trigger.utils.NodePort

alias of HostPort

trigger.utils.crypt_md5(passwd)

Returns an md5-crypt hash of a clear-text password.

To get md5-crypt from crypt(3) you must pass an 8-char string starting with ‘$1$’ and ending with ‘$’, resulting in a 12-char salt. This only works on systems where md5-crypt is default and is currently assumed to be Linux.

Parameters:

passwd – Password string to be encrypted

trigger.utils.parse_node_port(nodeport, delimiter=':')

Parse a string in format ‘hostname’ or ‘hostname:port’ and return them as a 2-tuple.

trigger.utils.strip_juniper_namespace(path, key, value)

Given a Juniper XML element, strip the namespace and return a 2-tuple.

This is designed to be used as a postprocessor with parse().

Parameters:

  • key – The attribute name of the element.

  • value – The value of the element.

trigger.utils.cli

Command-line interface utilities for Trigger tools. Intended for re-usable pieces of code like user prompts, that don’t fit in other utils modules.

class trigger.utils.cli.NullDevice

Used to supress output to sys.stdout (aka print).

Example:

>>> from trigger.utils.cli import NullDevice
>>> import sys
>>> print "1 - this will print to STDOUT"
1 - this will print to STDOUT
>>> original_stdout = sys.stdout  # keep a reference to STDOUT
>>> sys.stdout = NullDevice()     # redirect the real STDOUT
>>> print "2 - this won't print"
>>>
>>> sys.stdout = original_stdout  # turn STDOUT back on
>>> print "3 - this will print to SDTDOUT"
3 - this will print to SDTDOUT
class trigger.utils.cli.Whirlygig(start_msg='', done_msg='', max=100)

Prints a whirlygig for use in displaying pending operation in a command-line tool. Guaranteed to make the user feel warm and fuzzy and be 1000% bug-free.

Parameters:

  • start_msg – The status message displayed to the user (e.g. “Doing stuff:”)

  • done_msg – The completion message displayed upon completion (e.g. “Done.”)

  • max – Integer of the number of whirlygig repetitions to perform

Example:

>>> Whirlygig("Doing stuff:", "Done.", 12).run()
run()

Executes the whirlygig!

trigger.utils.cli.get_terminal_size()

Find and return stdouts terminal size as (height, width).

trigger.utils.cli.get_terminal_width()

Find and return stdout’s terminal width, if applicable.

trigger.utils.cli.get_user()

Return the name of the current user.

trigger.utils.cli.min_sec(secs)

Takes an epoch timestamp and returns string of minutes:seconds.

Parameters:

secs – Timestamp (in seconds)

>>> import time
>>> start = time.time()  # Wait a few seconds
>>> finish = time.time()
>>> min_sec(finish - start)
'0:11'
trigger.utils.cli.pretty_time(t)

Print a pretty version of timestamp, including timezone info. Expects the incoming datetime object to have proper tzinfo.

Parameters:

t – A datetime.datetime object

>>> import datetime
>>> from pytz import timezone
>>> localzone = timezone('US/Eastern')
<DstTzInfo 'US/Eastern' EST-1 day, 19:00:00 STD>
>>> t = datetime.datetime.now(localzone)
>>> print t
2011-07-19 12:40:30.820920-04:00
>>> print pretty_time(t)
09:40 PDT
>>> t = localzone.localize(datetime.datetime(2011,07,20,04,13))
>>> print t
2011-07-20 04:13:00-05:00
>>> print pretty_time(t)
tomorrow 02:13 PDT
trigger.utils.cli.print_severed_head()

Prints a demon holding a severed head. Best used when things go wrong, like production-impacting network outages caused by fat-fingered ACL changes.

Thanks to Jeff Sullivan for this best error message ever.

trigger.utils.cli.proceed()

Present a proceed prompt. Return True if Y, else False.

trigger.utils.cli.yesno(prompt, default=False, autoyes=False)

Present a yes-or-no prompt, get input, and return a boolean.

The default argument is ignored if autoyes is set.

Parameters:

  • prompt – Prompt text

  • default – Yes if True; No if False

  • autoyes – Automatically return True

Default behavior (hitting “enter” returns False):

>>> yesno('Blow up the moon?')
Blow up the moon? (y/N)
False

Reversed behavior (hitting “enter” returns True):

>>> yesno('Blow up the moon?', default=True)
Blow up the moon? (Y/n)
True

Automatically return True with autoyes; no prompt is displayed:

>>> yesno('Blow up the moon?', autoyes=True)
True

trigger.utils.importlib

Utils to import modules.

Taken verbatim from django.utils.importlib in Django 1.4.

trigger.utils.importlib.import_module(name, package=None)

Import a module and return the module object.

The package argument is required when performing a relative import. It specifies the package to use as the anchor point from which to resolve the relative import to an absolute import.

trigger.utils.importlib.import_module_from_path(full_path, global_name)

Import a module from a file path and return the module object.

Allows one to import from anywhere, something __import__() does not do. The module is added to sys.modules as global_name.

Parameters:

  • full_path – The absolute path to the module .py file

  • global_name – The name assigned to the module in sys.modules. To avoid confusion, the global_name should be the same as the variable to which you’re assigning the returned module.

trigger.utils.network

Functions that perform network-based things like ping, port tests, etc.

trigger.utils.network.address_is_internal(ip)

Determines if an IP address is internal to your network. Relies on networks specified in settings.INTERNAL_NETWORKS.

Parameters:

ip – IP address to test.

>>> address_is_internal('1.1.1.1')
False
trigger.utils.network.ping(host, count=1, timeout=5)

Returns pass/fail for a ping. Supports POSIX only.

Parameters:

  • host – Hostname or address

  • count – Repeat count

  • timeout – Timeout in seconds

>>> from trigger.utils import network
>>> network.ping('aol.com')
True
>>> network.ping('192.168.199.253')
False
trigger.utils.network.test_ssh(host, port=22, timeout=5, version=('SSH-1.99', 'SSH-2.0', 'dcos_sshd run in non-FIPS mode'))

Connect to a TCP port and confirm the SSH version. Defaults to SSHv2.

Note that the default of (‘SSH-1.99’, ‘SSH-2.0’) both indicate SSHv2 per RFC 4253. (Ref: http://en.wikipedia.org/wiki/Secure_Shell#Version_1.99)

Parameters:

  • host – Hostname or address

  • port – Destination port

  • timeout – Timeout in seconds

  • version – The SSH version prefix (e.g. “SSH-2.0”). This may also be a tuple of prefixes.

>>> test_ssh('localhost')
True
>>> test_ssh('localhost', version='SSH-1.5')
False
trigger.utils.network.test_tcp_port(host, port=23, timeout=5, check_result=False, expected_result='')

Attempts to connect to a TCP port. Returns a Boolean.

If check_result is set, the first line of output is retreived from the connection and the starting characters must match expected_result.

Parameters:

  • host – Hostname or address

  • port – Destination port

  • timeout – Timeout in seconds

  • check_result – Whether or not to do a string check (e.g. version banner)

  • expected_result – The expected result!

>>> test_tcp_port('aol.com', 80)
True
>>> test_tcp_port('aol.com', 12345)
False

trigger.utils.notifications

trigger.utils.notifications.handlers

trigger.utils.notifications.events

trigger.utils.rcs