Class: PilarCryptodemo::Blockchain

Inherits:
Object
  • Object
show all
Defined in:
lib/pilar_cryptodemo.rb

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize ⇒ Blockchain

Returns a new instance of Blockchain.



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# File 'lib/pilar_cryptodemo.rb', line 9

def initialize()
  @chain = []
  @current_transactions = []
  
  #generate genesis block
  new_block(100, 1)
end

Instance Attribute Details

#chain ⇒ Object (readonly)

Returns the value of attribute chain.



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# File 'lib/pilar_cryptodemo.rb', line 7

def chain
  @chain
end

Class Method Details

.hash(block) ⇒ Object 



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# File 'lib/pilar_cryptodemo.rb', line 62

def self.hash(block)
  block_string = block.to_json
  
  # return SHA256 for the given block
  Digest::SHA256.hexdigest(block_string)
end

.valid_proof(last_proof, proof) ⇒ Object 



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# File 'lib/pilar_cryptodemo.rb', line 69

def self.valid_proof(last_proof, proof)
  guess "#{last_proof}#{proof}"
  guess_hash = Digest::SHA256.hexdigest(guess)
  guess_hash.to_s[-4..-1] == '0000'
end

Instance Method Details

#hash(block) ⇒ Object 



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# File 'lib/pilar_cryptodemo.rb', line 57

def hash(block)
  Blockchain.hash(block)
  
end

#last_block ⇒ Object 



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# File 'lib/pilar_cryptodemo.rb', line 43

def last_block
  @chain[-1]
end

#new_block(proof, previousHash) ⇒ Object 



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# File 'lib/pilar_cryptodemo.rb', line 17

def new_block(proof, previousHash)
  block = {
    :index => @chain.count + 1,
    :timestamp => Time.now.to_i,
    :transactions => @current_transactions,
    :proof => proof,
    :previous_hash => previous_hash ||= self.hash(@chain[-1])
  }
  
  @current_transactions = []
  @chain.push(block)
  
  block
end

#new_transaction(sender, recipent, amount) ⇒ Object 



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# File 'lib/pilar_cryptodemo.rb', line 32

def new_transaction(sender, recipent, amount)
  @current_transactions.push({
    :sender => sender,
    :recipent => recipent,
    :amount => amount
  })
  
  @chain.index(last_block)
  
end

#proof_of_work(last_proof) ⇒ Object 



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# File 'lib/pilar_cryptodemo.rb', line 47

def proof_of_work(last_proof)
  #calculate
  
  proof = 0
  while !Blockchain.valid_proof(last_proof,proof) do
    proof += 1
  end
  proof
end