Class: Bitcoin::BlockFilter

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

Overview

Compact Block Filter github.com/bitcoin/bips/blob/master/bip-0158.mediawiki This implementation ported the implementation of Bitcoin Core’s blockfilter.cpp. github.com/bitcoin/bitcoin/blob/master/src/blockfilter.cpp

Constant Summary collapse

TYPE = 
{basic: 0}
BASIC_FILTER_P =

basic filter params

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BASIC_FILTER_M = 
784931

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(filter_type, filter, block_hash) ⇒ Bitcoin::BlockFilter

Constructor

Parameters:



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# File 'lib/bitcoin/block_filter.rb', line 24

def initialize(filter_type, filter, block_hash)
  @filter_type = filter_type
  @filter = filter
  @block_hash = block_hash
end

Instance Attribute Details

#block_hash ⇒ Object

Returns the value of attribute block_hash.



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# File 'lib/bitcoin/block_filter.rb', line 17

def block_hash
  @block_hash
end

#filter ⇒ Object

Returns the value of attribute filter.



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# File 'lib/bitcoin/block_filter.rb', line 16

def filter
  @filter
end

#filter_type ⇒ Object

Returns the value of attribute filter_type.



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# File 'lib/bitcoin/block_filter.rb', line 15

def filter_type
  @filter_type
end

Class Method Details

.build_from_block(filter_type, block, prev_out_scripts) ⇒ Bitcoin::BlockFilter

Build BlockFilter from the block data.

Parameters:

  • filter_type (Integer) —

    a filter type(basic or extended).

  • block (Bitcoin::Block) —

    target block object.

  • prev_out_scripts (Array[Bitcoin::Script]) —

    The previous output script (the script being spent) for each input, except for the coinbase transaction.

Returns:



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# File 'lib/bitcoin/block_filter.rb', line 35

def self.build_from_block(filter_type, block, prev_out_scripts)
  block_hash = block.block_hash.htb[0...16]
  filter = case filter_type
           when TYPE[:basic]
             GCSFilter.new(block_hash, BASIC_FILTER_P, BASIC_FILTER_M, elements: build_basic_filter_elements(block, prev_out_scripts))
           else
             raise "unknown filter type: #{filter_type}."
           end
  BlockFilter.new(filter_type, filter, block.block_hash)
end

.decode(filter_type, block_hash, encoded) ⇒ Bitcoin::BlockFilter

Decode Block Filter from encoded filter

Parameters:

  • filter_type (Integer) —

    filter type.

  • block_hash (String) —

    block hash with hex format. not little endian.

  • encoded (String) —

    encoded_filter with hex format.

Returns:



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# File 'lib/bitcoin/block_filter.rb', line 51

def self.decode(filter_type, block_hash, encoded)
  filter = case filter_type
           when TYPE[:basic]
            GCSFilter.new(block_hash.htb[0...16], BASIC_FILTER_P, BASIC_FILTER_M, encoded_filter: encoded)
          else
            raise "unknown filter type: #{filter_type}."
           end
  BlockFilter.new(filter_type, filter, block_hash)
end

Instance Method Details

#encoded_filter ⇒ Object

get encoded filter.



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# File 'lib/bitcoin/block_filter.rb', line 75

def encoded_filter
  filter.encoded
end

#filter_hash ⇒ String

calculate filter hash.

Returns:

  • (String) —

    this filter hash with hex format.



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# File 'lib/bitcoin/block_filter.rb', line 63

def filter_hash
  Bitcoin.double_sha256(encoded_filter.htb).bth
end

#header(prev_header) ⇒ String

calculate filter header which calculates from previous filter header and current filter hash.

Parameters:

  • prev_header (String) —

    a previous header with hex format.

Returns:

  • (String) —

    header of this filter with hex format.



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

def header(prev_header)
  Bitcoin.double_sha256(filter_hash.htb + prev_header.htb).bth
end