Class: Bitcoin::BlockHeader

Inherits:
Object show all
Defined in:
lib/bitcoin/block_header.rb

Overview

Block Header

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(version, prev_hash, merkle_root, time, bits, nonce) ⇒ BlockHeader

Returns a new instance of BlockHeader.



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# File 'lib/bitcoin/block_header.rb', line 13

def initialize(version, prev_hash, merkle_root, time, bits, nonce)
  @version = version
  @prev_hash = prev_hash
  @merkle_root = merkle_root
  @time = time
  @bits = bits
  @nonce = nonce
end

Instance Attribute Details

#bits ⇒ Object

Returns the value of attribute bits.



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# File 'lib/bitcoin/block_header.rb', line 10

def bits
  @bits
end

#merkle_root ⇒ Object

Returns the value of attribute merkle_root.



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# File 'lib/bitcoin/block_header.rb', line 8

def merkle_root
  @merkle_root
end

#nonce ⇒ Object

Returns the value of attribute nonce.



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# File 'lib/bitcoin/block_header.rb', line 11

def nonce
  @nonce
end

#prev_hash ⇒ Object

Returns the value of attribute prev_hash.



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# File 'lib/bitcoin/block_header.rb', line 7

def prev_hash
  @prev_hash
end

#time ⇒ Object

unix timestamp



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# File 'lib/bitcoin/block_header.rb', line 9

def time
  @time
end

#version ⇒ Object

Returns the value of attribute version.



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# File 'lib/bitcoin/block_header.rb', line 6

def version
  @version
end

Class Method Details

.parse_from_payload(payload) ⇒ Object 



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# File 'lib/bitcoin/block_header.rb', line 22

def self.parse_from_payload(payload)
  version, prev_hash, merkle_root, time, bits, nonce = payload.unpack('Va32a32VVV')
  new(version, prev_hash.bth, merkle_root.bth, time, bits, nonce)
end

Instance Method Details

#==(other) ⇒ Object 



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# File 'lib/bitcoin/block_header.rb', line 76

def ==(other)
  other && other.to_payload == to_payload
end

#block_hash ⇒ Object 



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# File 'lib/bitcoin/block_header.rb', line 43

def block_hash
  calc_hash
end

#block_id ⇒ Object

block hash(big endian)



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# File 'lib/bitcoin/block_header.rb', line 48

def block_id
  block_hash.rhex
end

#difficulty_target ⇒ Object

compute difficulty target from bits.



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# File 'lib/bitcoin/block_header.rb', line 32

def difficulty_target
  exponent = ((bits >> 24) & 0xff)
  mantissa = bits & 0x7fffff
  mantissa *= -1 if (bits & 0x800000) > 0
  (mantissa * 2 ** (8 * (exponent - 3)))
end

#hash ⇒ Object 



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# File 'lib/bitcoin/block_header.rb', line 39

def hash
  calc_hash.to_i(16)
end

#to_payload ⇒ Object 



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# File 'lib/bitcoin/block_header.rb', line 27

def to_payload
  [version, prev_hash.htb, merkle_root.htb, time, bits, nonce].pack('Va32a32VVV')
end

#valid? ⇒ Boolean

evaluate block header

Returns:

  • (Boolean) 


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# File 'lib/bitcoin/block_header.rb', line 53

def valid?
  valid_pow? && valid_timestamp?
end

#valid_pow? ⇒ Boolean

evaluate valid proof of work.

Returns:

  • (Boolean) 


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# File 'lib/bitcoin/block_header.rb', line 58

def valid_pow?
  block_id.hex < difficulty_target
end

#valid_timestamp? ⇒ Boolean

evaluate valid timestamp. en.bitcoin.it/wiki/Block_timestamp

Returns:

  • (Boolean) 


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# File 'lib/bitcoin/block_header.rb', line 64

def valid_timestamp?
  time <= Time.now.to_i + Bitcoin::MAX_FUTURE_BLOCK_TIME
end

#work ⇒ Integer

compute chain work of this block.

Returns:



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# File 'lib/bitcoin/block_header.rb', line 70

def work
  target = difficulty_target
  return 0 if target < 1
  115792089237316195423570985008687907853269984665640564039457584007913129639936.div(target + 1) # 115792089237316195423570985008687907853269984665640564039457584007913129639936 is 2**256
end