Module: StringBase

Extended by:
StringBase
Included in:
StringBase
Defined in:
lib/common/string_base.rb

Constant Summary collapse

KEYS = 
'bcdghjklmnpqrstvwxyz'
MULTIPLIER = 
99

Instance Method Summary collapse

Instance Method Details

#decode(string) ⇒ Object 



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# File 'lib/common/string_base.rb', line 21

def decode string
  ring = Hash[KEYS.chars.map.with_index.to_a]
  base = KEYS.length
  ret = string.reverse.chars.map.with_index.inject(0) do |sum,(char,i)|
    sum + ring[char] * (base**i)
  end
  raise 'Invalid decode base' if ret%MULTIPLIER>0
  ret/MULTIPLIER
end

#encode(value) ⇒ Object 



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# File 'lib/common/string_base.rb', line 9

def encode value
  value = value * MULTIPLIER
  ring = Hash[KEYS.chars.map.with_index.to_a.map(&:reverse)]
  base = KEYS.length
  result = []
  until value == 0
    result << ring[ value % base ]
    value /= base
  end
  result.reverse.join
end

#extract(url_part) ⇒ Object

extract ID from url



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# File 'lib/common/string_base.rb', line 32

def extract(url_part)
  id_str = url_part.split('-').last
  return nil unless id_str
  StringBase.decode(id_str) rescue nil
end