asterisklint 0.4.0

Asterisk PBX configuration syntax checker
=========================================

.. image:: https://bettercodehub.com/edge/badge/ossobv/asterisklint

Asterisklint is a suite of tools to check syntax of your Asterisk PBX
configuration files.

Alright, enough talking. Some examples please.


Invocation
----------

.. code-block:: console

$ asterisklint
usage: asterisklint [-h] COMMAND
asterisklint: error: the following arguments are required: COMMAND

$ asterisklint ls
builtin:
ls List available commands.

/usr/lib/python/dist-packages:
dialplan-check Do sanity checks on dialplan. Takes 'extensions.conf'
as argument. Suppress error classes using ALINT_IGNORE.
dialplan-show Show dialplan like Asterisk does with CLI command
"dialplan show". Takes 'extensions.conf' as argument.
func_odbc-check Do sanity checks on func_odbc.conf. Takes
'func_odbc.conf' as argument. Suppress error classes
using ALINT_IGNORE.
ident-scan Report similarly named contexts, labels and variables.
Takes 'extensions.conf' as argument. All parse errors
are suppressed.
modules-show Show which modules, apps and functions are used by the
dialplan. Takes 'extensions.conf' as argument.

Place custom commands in ~/.asterisklint/asterisklint/commands.


Take this little dialplan snippet, that we'll call ``extensions.conf``::

[default]
exten => _8[2-9]x,1,NoOp
same => n,GoSub(somewhere,s,1(argument1,argument2)
same => n,Payback(audiofile)

Now run the ``dialplan-check`` command on it:

.. code-block:: console

$ ALINT_IGNORE=H_DP_ asterisklint dialplan-check extensions.conf
extensions.conf:2 H_PAT_NON_CANONICAL: pattern '_8[2-9]x' is not in the canonical form '_8NX'
extensions.conf:3 W_APP_BAD_CASE: app 'GoSub' does not have the proper Case 'Gosub'
extensions.conf:3 W_APP_BALANCE: app data '1(argument1,argument2' looks like unbalanced parentheses/quotes/curlies
extensions.conf:4 E_APP_MISSING: app 'Payback' does not exist, dialplan will halt here!
extensions.conf:3 E_DP_GOTO_NOCONTEXT: context not found for goto to somewhere, s, 1

It had a lot to complain about that little snippet. But it was right. We
even suppressed two hints about a missing ``[general]`` and ``[global]``
context using ``ALINT_IGNORE``.

Not everything it checks is documented, and it does not check everything
that we like yet. But it's a start. Bug reports are welcome. Feature requests
prefer to be accompanied by a patch :-)

Try out ``modules-show`` if you use ``autoload=no`` in your ``modules.conf``.

All commands show help if asked:

.. code-block:: console

$ asterisklint modules-show --help
usage: asterisklint modules-show [-h] [--func-odbc FUNC_ODBC_CONF]
[EXTENSIONS_CONF]

Show which modules, apps and functions are used by the dialplan. Useful when
you use autoload=no in your modules.conf. Beware that you do need more modules
than just these listed.

positional arguments:
EXTENSIONS_CONF path to extensions.conf

optional arguments:
-h, --help show this help message and exit
--func-odbc FUNC_ODBC_CONF
path to func_odbc.conf, will be read automatically if
found in same the same dir as extensions.conf; set
empty to disable


Installation
------------

Installation is a matter of ``python3 setup.py install``. Or, for more convenience,
install a PyPI uploaded version through ``pip3(1)``:

.. code-block:: console

$ sudo pip3 install asterisklint
...
Successfully installed asterisklint


The ``dialplan-check`` comes in handy as a git commit hook, for example
``.git/hooks/pre-commit``:

.. code-block:: sh

#!/bin/sh
export ALINT_IGNORE= # adjust as needed

asterisklint dialplan-check PATH/TO/extensions.conf
ret=$?
if test $ret -ne 0; then
echo >&2
echo 'One or more dialplan syntax errors. Please fix before committing.' >&2
exit $ret
fi

exit 0


TODO
----

* Expression parsing.
* Web: state is kept between requests:
- on 500-error, the next user may get older errors (because of the
messagedef singleton)
- the BackGround/Background hack is stored between requests
* Log/store Set'd variables and compare against Read variables. Also log
variables Set through the ARRAY() function. (And HASH?)
* Fix various includes issues:
- Recursive #includes probably make asterisklint run out of stack.
- Add checks for recursive dialplan-includes.
- Scan for missing dialplan-includes.
* Trim CALLERID match (as used in FreePBX dialplan).
* Func_odbc parsing improvements:
- check for missing synopsis/syntax (compare syntax to ARGn count)
- check for correct usage of VAL (write only) and ARG and missing SQL_ESC
- yield the odbc functions instead of contexts like it does now
(See more in func_odbc.py.)
* Add ``app-check`` command to do dialplan checks of individual lines.
* Add ``expr-check`` command to do expression (``$[...]``) checks.
* Allow multiline variables using += (key=val; key+=more-val).
* Investigate whether exten=>s,n(label)... exten=>s,label+10... is valid.
* For the Goto/Gosub-visiting:
- Attempt to match contexts by regex if there are $VARs involved?
- Allow a "noqa" style exceptions to be placed in a comment?
* Improve documentation as needed.
* Before 1.0, start adding versioning -- including semver -- so users can
depend on a stable API from their custom scripts. Also version the scripts
(commands) so they won't talk to older/newer libs if that poses a problem.


BUGS
----

* The library is very much in flux. Don't expect it to stabilize any time
soon. Pay attention to versions!
* Multiline comments (``;-- ... --;``) are unsupported. Does anyone use those?
* Limits aren't checked (dialplan lines are limited at 255 or 8191 bytes
for LOW_MEMORY and normal mode respectively).
* The library/suite is Python3 only. Right now the effort to make it Python2
compatible is larger than the demand. In the future Python2 compatibility
will become even less relevant.


Author
------

Walter Doekes, OSSO B.V. 2015-2017



0.4.0 (2017-04-05)
~~~~~~~~~~~~~~~~~~

Bug fixes:

* When doing dialplan-file mutations, operate on the symlink target
instead of replacing the symlink.
* Don't install README files into /usr, but in
/usr/share/doc/asterisklint (or with a different prefix).
* Also search in included contexts for priority labels.

Improvements:

* Add various apps:
- Authenticate, ControlPlayback, PickupChan
- PickupOld1v4 (a workaround, see ASTERISK-26464)
- VoiceMailPlayMsg, VMSayName,
- ContinueWhile, EndWhile, ExitWhile, While,
- AGI, DeadAGI, EAGI,
- StopMusicOnHold
* Add various functions:
- DB, DB_EXISTS, DB_KEYS, DB_DELETE,
- MD5, TIMEOUT
- LOCAL, LOCAL_PEEK, STACK_PEEK
* Add initial checks of function parameters: nothing more than the
parentheses check we already used on undefined apps.
* Add application Set() support. Add function SET() support. This also
enables checking calls to writable functions.
* Allow both the "BackGround" and "Background" spelling, as long as
you choose one consistently.
* A bunch of refactoring to make BetterCodeHub happy. If you've made
custom subcommands, look at the MainBase class.
* Add test with Asterisk 13 sample dialplan as input.
* Add web frontend into repository.

0.3.0 (2016-06-08)
~~~~~~~~~~~~~~~~~~

* Add preliminary Goto/Gosub scanning: the dialplan-check now tries to
find non-existent goto destinations. New error classes:
E_DP_GOTO_CONTEXT_NOLABEL, E_DP_GOTO_NOCONTEXT, E_DP_GOTO_NOLABEL,
W_DP_GOTO_CONTEXT_NOEXTEN.
* Add preliminary app argument checking. New error classes:
E_APP_ARG_IFCONST, E_APP_ARG_IFEMPTY, E_APP_ARG_SYNTAX.
* Add new command: ident-scan. It lists used contexts, labels and
variables and does a poor attempt at finding typo's by comparing
them against each other.
* Add Asterisk apps: NoCDR, Record.
* The commands taking a path to extensions.conf now default to scanning
for it in the current directory.
* Python3.5 testcase compatibility fix.

0.2.1 (2016-01-29)
~~~~~~~~~~~~~~~~~~

* Don't look in __init__ for custom commands.

0.2.0 (2016-01-29)
~~~~~~~~~~~~~~~~~~

* Add partial func_odbc checking.
* Add new command: func_odbc-check
* Do func_odbc checks for modules-show and dialplan-show, so you don't
get flooded with E_FUNC_MISSING errors if you use func_odbc.
* Fix a few variable/dialplan parsing bugs, improve some.

0.1.0 (2016-01-15)
~~~~~~~~~~~~~~~~~~

* Initial release.
* The following commands are available:
dialplan-check, dialplan-show, modules-show