Puppet Function: percona_hash_merge

Defined in:
lib/puppet/parser/functions/percona_hash_merge.rb
Function type:
Ruby 3.x API

Overview

percona_hash_merge() ⇒ Any

Function: percona_hash_merge

Merges hashes. If multiple hashes are provided, the ones that are in the front of the argument list override values from hashes that come later in the array.

You can also use this function on a single hash. In this case, it is obviously not merged but we still convert the key-value pairs to the correct format for augeas/print_percona_hash.

Arguments: hashes with ‘key => value’ pairs…

If the value is a string, present and absent are special values which will result in:

{:value => :undef, :ensure => 'present',:section => 'mysqld',}

or

{:value => :undef, :ensure => 'absent, :section => 'mysqld', :key => 'value' }

To explicitly use the value present (or absent), use

{:value => 'present'} or {:value => 'absent' }

Example:

$my_settings = {
  'mysqld/tmpdir'                        => '/var/tmp',
  'mysqld/log-queries-not-using-indexes' => 'absent',
}

$global_settings = {
  'mysqld/tmpdir'           => '/tmp',
  'mysqld/max_binlog_size'  => '100M',
}

$merged = percona_hash_merge($my_settings, $global_settings)

This will result in an combined hash looking like this:

{
  'mysqld/log-queries-not-using-indexes' => {
    :value   => :undef,
    :section => 'mysqld',
    :key     => 'log-queries-not-using-indexes',
    :ensure  => 'absent',
  },
  'mysqld/max_binlog_size' => {
    :value   => '100M',
    :section => 'mysqld',
    :key     => 'max_binlog_size',
    :ensure  => 'present',
   },
  'mysqld/tmpdir' => {
    :value   => '/var/tmp',
    :section => 'mysqld',
    :key     => 'tmpdir',
    :ensure  => 'present',
  },
}

As you can see, this is perfect to use in combination in your template with the print_percona_hash function(). It also is ready to use in combination with the create_resources function. I would almost suggest

create_resources('percona::augeas', $merged)

Note: When specifying an array as a value, you could think that the array

would also be merged, this is NOT the case. An array behaves like a
string would, the value gets overridden completely.

Returns:

  • (Any) 


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# File 'lib/puppet/parser/functions/percona_hash_merge.rb', line 4

newfunction(:percona_hash_merge,
  :type => :rvalue, :doc => <<-EODOC
== Function: percona_hash_merge

Merges hashes. If multiple hashes are provided, the ones
that are in the front of the argument list override values from
hashes that come later in the array.

You can also use this function on a single hash. In this case, it is
obviously not merged but we still convert the key-value pairs to
the correct format for augeas/print_percona_hash.

=== Arguments: hashes with 'key => value' pairs...

If the value is a string, present and absent are special values
which will result in:

  {:value => :undef, :ensure => 'present',:section => 'mysqld',}

or

  {:value => :undef, :ensure => 'absent, :section => 'mysqld', :key => 'value' }

To explicitly use the value present (or absent), use

  {:value => 'present'} or {:value => 'absent' }


=== Example:

  $my_settings = {
    'mysqld/tmpdir'                        => '/var/tmp',
    'mysqld/log-queries-not-using-indexes' => 'absent',
  }

  $global_settings = {
    'mysqld/tmpdir'           => '/tmp',
    'mysqld/max_binlog_size'  => '100M',
  }

  $merged = percona_hash_merge($my_settings, $global_settings)

This will result in an combined hash looking like this:

  {
    'mysqld/log-queries-not-using-indexes' => {
      :value   => :undef,
      :section => 'mysqld',
      :key     => 'log-queries-not-using-indexes',
      :ensure  => 'absent',
    },
    'mysqld/max_binlog_size' => {
      :value   => '100M',
      :section => 'mysqld',
      :key     => 'max_binlog_size',
      :ensure  => 'present',
     },
    'mysqld/tmpdir' => {
      :value   => '/var/tmp',
      :section => 'mysqld',
      :key     => 'tmpdir',
      :ensure  => 'present',
    },
  }

As you can see, this is perfect to use in combination in your template with
the print_percona_hash function(). It also is ready to use in combination with
the create_resources function. I would almost suggest

  create_resources('percona::augeas', $merged)

Note: When specifying an array as a value, you could think that the array
      would also be merged, this is NOT the case. An array behaves like a
      string would, the value gets overridden completely.

EODOC
) do |args|

  args = [args] unless args.is_a?(Array)
  args.flatten!

  sanitized = []
  # Sanitize ALL the hashes! Add/merge with our keyset_default.
  args.each do |hash|
    # Yeah, we only handle hashes well.
    raise(Puppet::ParseError, 'percona_hash_merge(): Arguments should be hashes') unless hash.is_a?(Hash)
    sanitized << function_percona_hash_sanitize([hash])
  end

  # The first hash in the array (first argument) is the most correct.
  result_hash = sanitized.shift

  ## Merge them here ;)
  sanitized.each do |hash|
    hash.each do |k,v|
      if ! result_hash.include?(k)
        result_hash[k] = v
      end
    end
  end

  result_hash

end