*dnsserial.txt* another DNS-zone serial number updater

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          | |_| | |\  |___) \__ \  __/ |  | | (_| | |~
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          Another DNS-zone serial number updater.

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CONTENTS                                                   *DNSserialContents*

    1. Introduction ......... |DNSserial|
    2. Usage ................ |DNSserialUsage|
    3. Patterns ............. |DNSserialPatterns|
    4. Configuration ........ |DNSserialConfiguration|
    5. Custom patterns ...... |DNSserialCustomPatterns|
        5.1 regex ........... |DNSserialCustomPatterns-regex|
        5.2 matching ........ |DNSserialCustomPatterns-matching|
        5.3 examples ........ |DNSserialCustomPatterns-examples|
    6. License .............. |DNSserialLicense|

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Section 1: Introduction                                            *DNSserial*

I know this not the first vim plugin available to update a DNS-zone serial
number. Here is a few reasons why I chose not to use the canonical one:

 - there is no license and therefore it is not free;
 - it is unmaintained;
 - it is bugged;
 - it lacks functionalities.

It chose not to fork the original plugin but to write a new one from scratch
mainly for legal purposes, but also because I did not found the code as simple
as I expected.

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Section 2: Usage                                              *DNSserialUsage*

By default, each time you save a bindzone file, the script will look for the
DNS serial number and update it. You can also update it without saving the
file by invoking the :DNSSerialUpdate function.

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Section 3: Patterns                                        *DNSserialPatterns*

In order to be detected, the DNS serial number must match one the following
pattern:

 - YYYYMMDDXX ; serial
   * YYYY is the year (4 digits, must start by either 19 or 2);
   * MM is the month (2 digits);
   * DD is the day (2 digits);
   * XX is any non-negative number (1 or more digits);
   * the word serial is not case-sensitive;
   * there can be any number of blanks on each sides of the semicolon.

 - SSSSSSSSSS ; serial
   * SSSSSSSSSS is the UNIX tiemstamp (10 digits, must start by 1);
   * the word serial is not case-sensitive;
   * there can be any number of blanks on each sides of the semicolon.

 - XX ; serial
   * XX is any non-negative number (1 or more digits);
   * the word serial is not case-sensitive;
   * there can be any number of blanks on each sides of the semicolon.

According to those patterns, only dates between 1900 and 2999 will be
detected; however this should not be a problem at all. Most importantly, only
timestamps between September 9 2001 and March 17 2030 will be detected.

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Section 4: Configuration                              *DNSserialConfiguration*

You can set several configuration variables in your vimrc:

 - g:dnsserial_auto_update: Defines whether or not the serial is updated when
   the zone file is saved (default is 1, set it to 0 to disable).
 - g:dnsserial_custom_patterns: List of customs patterns that will be added to
   the default ones. Order matters, the first matching patters will be used.
   Customs patterns will be tested before the default ones.
 - g:dnsserial_patterns: List of default patterns. It is not advised to change
   it.

==============================================================================
Section 5: Custom patterns                           *DNSserialCustomPatterns*

A pattern is defined by a dictionary with two keys: regex and matching.

------------------------------------------------------------------------------
Section 5.1: regex                             *DNSserialCustomPatterns-regex*

Contains the regular expression that will be used to search the document for
the serial number. All the components of the serial number must be captured
with parenthesis.

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Section 5.1: matching                       *DNSserialCustomPatterns-matching*

This is a list of every components of the serial number. Each component is
defined by a dictionary. The type key must be present and contain one of the
allowed types. Depending on the type, several additional keys might be
defined. Authorized types and their options are:

 - raw: Raw string.
 - integer: An integer that will be incremented.
 - offset (int): set the offset by which the integer is incremented. Default
   is 1.
 - padding (int): Force the integer to be 0-padded on the associated number of
   digits.
 - date_reset (bool): If set to 1 and a the serial contains a date, the
   integer will be reseted to 0 if the date is updated. Default is 0.
 - date: A formated date that will be updated to the current one.
 - fmt (string, mandatory) : the date format according to the strftime()
   specifications. See :help strftime for more details.

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Section 5.1: examples                       *DNSserialCustomPatterns-examples*

A simple pattern matching a serial defined as an integer and followed by a
comment starting by the word serial is:

    {
      'regex': '\(\d\+\)\s*;\s*\cserial',
      'matching': [
        {'type': 'integer'}
      ]
    }

The same example, but having the serial number starting by the current date
(YYYYMMDD) and the integer padded on two digits:

    {
      'regex': '\(\d\{8}\)\(\d\+\)\s*;\s*\cserial',
      'matching': [
        {'type': 'date', 'fmt': '%Y%m%d'},
        {'type': 'integer', 'padding': 2, 'date_reset': 1}
      ]
    }

==============================================================================
Section 6: License                                          *DNSserialLicense*

DNSserial is Copyright 2015 Rodolphe Breard and is licensed under the Apache
License, Version 2.0.