Class: Omnizip::Parity::Par2Creator

Inherits:
Object
  • Object
show all
Defined in:
lib/omnizip/parity/par2_creator.rb

Overview

PAR2 parity archive creator

Creates PAR2 recovery files using Reed-Solomon error correction. PAR2 files allow recovery of corrupted or missing data blocks.

Examples:

Create PAR2 files for an archive

creator = Par2Creator.new(redundancy: 10, block_size: 16384)
creator.add_file('important.zip')
creator.create('important')
# Creates: important.par2, important.vol00+01.par2, etc.

Multiple files with custom settings

creator = Par2Creator.new(
  redundancy: 5,
  block_size: 32768,
  progress: ->(pct) { puts "Progress: #{pct}%" }
)
creator.add_file('file1.dat')
creator.add_file('file2.dat')
creator.create('backup')

Defined Under Namespace

Classes: FileInfo

Constant Summary collapse

PACKET_SIGNATURE =

PAR2 packet signature

"PAR2\x00PKT".b.freeze
PACKET_TYPE_MAIN =

Packet type identifiers

"PAR 2.0\x00Main\x00\x00\x00\x00"
PACKET_TYPE_FILE_DESC = 
"PAR 2.0\x00FileDesc"
PACKET_TYPE_IFSC = 
"PAR 2.0\x00IFSC\x00\x00\x00\x00"
PACKET_TYPE_RECOVERY = 
"PAR 2.0\x00RecvSlic"
DEFAULT_BLOCK_SIZE =

Default block size (16KB)

16384

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(redundancy: 5, block_size: DEFAULT_BLOCK_SIZE, progress: nil) ⇒ Par2Creator

Initialize PAR2 creator

Parameters:

  • redundancy (Integer) (defaults to: 5) —

    Redundancy percentage (0-100)

  • block_size (Integer) (defaults to: DEFAULT_BLOCK_SIZE) —

    Block size in bytes

  • progress (Proc, nil) (defaults to: nil) —

    Progress callback proc



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# File 'lib/omnizip/parity/par2_creator.rb', line 69

def initialize(redundancy: 5, block_size: DEFAULT_BLOCK_SIZE,
progress: nil)
  @redundancy = validate_redundancy(redundancy)
  @block_size = validate_block_size(block_size)
  @progress_callback = progress
  @files = []
  @set_id = generate_set_id
end

Instance Attribute Details

#block_size ⇒ Integer (readonly)

Returns Block size in bytes.

Returns:

  • (Integer) —

    Block size in bytes



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# File 'lib/omnizip/parity/par2_creator.rb', line 42

def block_size
  @block_size
end

#files ⇒ Array<Hash> (readonly)

Returns Files to protect.

Returns:

  • (Array<Hash>) —

    Files to protect



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# File 'lib/omnizip/parity/par2_creator.rb', line 48

def files
  @files
end

#progress_callback ⇒ Proc? (readonly)

Returns Progress callback.

Returns:

  • (Proc, nil) —

    Progress callback



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# File 'lib/omnizip/parity/par2_creator.rb', line 51

def progress_callback
  @progress_callback
end

#redundancy ⇒ Integer (readonly)

Returns Redundancy percentage (0-100).

Returns:

  • (Integer) —

    Redundancy percentage (0-100)



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# File 'lib/omnizip/parity/par2_creator.rb', line 45

def redundancy
  @redundancy
end

Instance Method Details

#add_file(file_path) ⇒ Object

Add file to PAR2 set

Parameters:

  • file_path (String) —

    Path to file

Raises:

  • (ArgumentError) —

    if file doesn't exist



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# File 'lib/omnizip/parity/par2_creator.rb', line 82

def add_file(file_path)
  raise ArgumentError, "File not found: #{file_path}" unless
    File.exist?(file_path)

  file_info = analyze_file(file_path)
  @files << file_info
end

#create(base_name) ⇒ Array<String>

Create PAR2 recovery files

Parameters:

  • base_name (String) —

    Base name for PAR2 files

Returns:

  • (Array<String>) —

    Paths to created PAR2 files



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# File 'lib/omnizip/parity/par2_creator.rb', line 94

def create(base_name)
  validate_files!

  # CRITICAL FIX: Sort files by file_id (MD5 hash) to match PAR2 spec
  # Par2cmdline creates recovery blocks with files sorted by file_id MD5.
  # The verifier also sorts by file_id, so ALL operations
  # (file descriptions, IFSC packets, recovery blocks) must use the same order.
  @files.sort_by!(&:file_id)

  # Calculate total blocks and recovery blocks needed
  total_blocks = calculate_total_blocks
  recovery_blocks = calculate_recovery_blocks(total_blocks)

  report_progress(0, "Initializing PAR2 creation")

  # Create main PAR2 index file
  index_file = create_index_file(base_name)

  # Create recovery volume files
  volume_files = create_recovery_volumes(
    base_name,
    recovery_blocks,
    total_blocks,
  )

  report_progress(100, "PAR2 creation complete")

  [index_file] + volume_files
end