Module: OpenASN::CidrUtils

Defined in:
lib/openasn/cidr_utils.rb

Overview

Range math for the Tier B executor. Mirrors the data pipeline's semantics exactly (adjacent ranges merge; inputs may overlap freely).

Class Method Summary collapse

Class Method Details

.merge(ranges) ⇒ Object

Merge overlapping AND adjacent ranges. Critical for Apple's relay list: ~280k rows collapse dramatically once merged, which is the difference between a fat linear file and a lookup-friendly overlay.



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# File 'lib/openasn/cidr_utils.rb', line 23

def merge(ranges)
  return [] if ranges.empty?

  sorted = ranges.sort_by { |r| [r[0], r[1]] }
  merged = [[sorted[0][0], sorted[0][1]]]
  sorted.each do |(s, e)|
    last = merged.last
    if s <= last[1] + 1
      last[1] = e if e > last[1]
    else
      merged << [s, e]
    end
  end
  merged
end

.parse(token) ⇒ Object

"1.2.3.0/24" | "1.2.3.4" -> [family, start_int, end_int] | nil (junk)



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# File 'lib/openasn/cidr_utils.rb', line 12

def parse(token)
  ip = IPAddr.new(token.strip)
  r = ip.to_range
  [ip.ipv4? ? :ipv4 : :ipv6, r.first.to_i, r.last.to_i]
rescue IPAddr::Error
  nil
end

.ranges_by_family(tokens) ⇒ Object

tokens (CIDRs/IPs, junk tolerated) -> { ipv4: merged, ipv6: merged }



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# File 'lib/openasn/cidr_utils.rb', line 40

def ranges_by_family(tokens)
  out = { ipv4: [], ipv6: [] }
  tokens.each do |token|
    family, s, e = parse(token)
    out[family] << [s, e] if family
  end
  { ipv4: merge(out[:ipv4]), ipv6: merge(out[:ipv6]) }
end