Class: Hash

Inherits:
Object
  • Object
show all
Defined in:
lib/utils/extend/hash.rb

Overview

Reopen the core ruby Hash class and add the below methods to it.

Direct Known Subclasses

SafeDb::DataStore

Instance Method Summary collapse

Instance Method Details

#log_contents ⇒ Object

Note:

This behaviour does not consider that SECRETS may be inside the key value maps - it logs itself without a care in the world. This functionality must be included if this behaviourr is used by any cryptography classes.

This method adds (logging its own contents) behaviour to the standard library Hash class.

The DEBUG log level is used for logging. To change this create a new parameterized method.



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# File 'lib/utils/extend/hash.rb', line 58

def log_contents

  log.debug(x) { "# --- ----------------------------------------------" }
  log.debug(x) { "# --- Map has [#{self.length}] key/value pairs." }
  log.debug(x) { "# --- ----------------------------------------------" }

  self.each do |the_key, the_value|

    padded_key = sprintf '%-33s', the_key
    log.debug(x) { "# --- #{padded_key} => #{the_value}" }

  end

  log.debug(x) { "# --- ----------------------------------------------" }

end

#merge_recursively!(merge_me) ⇒ Object

Recursively merge (deep merge) this Hash data structure with another given in the parameter.

The core ruby merge() instance method only performs first level merges which is not ideal in order to intelligently merge a deep tree.

Merge Behaviour

Currently this behaviour works only for Hash data structures that have string keys (only) and either string or Hash values. It is interesting only when duplicate keys are encountered at the same level. If the duplicate key’s value is

  1. a String - the incoming value is rejected and logged

  2. a Hash - the method is recalled to recursively merge

Parameters:

  • merge_me (Hash) —

    the incoming hash data structure to merge



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# File 'lib/utils/extend/hash.rb', line 24

def merge_recursively!( merge_me )

  self.merge!( merge_me ) do | key, value_1, value_2 |

    is_mergeable = value_1.kind_of?( Hash   ) && value_2.kind_of?( Hash   )
    are_both_str = value_1.kind_of?( String ) && value_2.kind_of?( String )
    not_the_same = are_both_str && ( value_1 != value_2 )

    reject_message( key, value_1, value_2 ) if not_the_same
    value_1.merge_recursively!( value_2 ) if is_mergeable
    value_1

  end

end

#reject_message(key, value_1, value_2) ⇒ Object

Print a line to standard out stating that a same key (duplicate) map entry has been encountered and here is the one we are rejecting.



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# File 'lib/utils/extend/hash.rb', line 43

def reject_message( key, value_1, value_2 )
  puts "Refused to allow { #{key} => #{value_2} } to overwrite { #{key} => #{value_1} }"
end