Class: Cabriolet::BaseCompressor

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

Overview

Abstract base class for all format compressors

Implements Template Method pattern:

  • Defines common compression workflow in generate()

  • Subclasses implement format-specific hooks

Provides:

  • File management via FileManager

  • Common initialization pattern

  • Template method for generation workflow

  • Hook methods for format customization

  • Helper methods for common operations

Subclasses must implement:

  • build_structure(options) - Create format-specific structure

  • write_format(output_handle, structure) - Write binary data

Subclasses may override:

  • validate_generation_prerequisites!(options) - Custom validation

  • post_generation_hook(output_file, structure, bytes) - Cleanup/logging

Examples:

Creating a format compressor

class MyFormatCompressor < BaseCompressor
  protected

  def build_structure(options)
    { header: build_header, files: collect_files }
  end

  def write_format(output_handle, structure)
    io_system.write(output_handle, structure[:header].to_binary_s)
  end
end

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(io_system = nil, algorithm_factory = nil) ⇒ BaseCompressor

Initialize compressor with I/O and algorithm dependencies



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# File 'lib/cabriolet/base_compressor.rb', line 47

def initialize(io_system = nil, algorithm_factory = nil)
  @io_system = io_system || System::IOSystem.new
  @algorithm_factory = algorithm_factory || Cabriolet.algorithm_factory
  @file_manager = FileManager.new
end

Instance Attribute Details

#algorithm_factory ⇒ Object (readonly)

Returns the value of attribute algorithm_factory.



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# File 'lib/cabriolet/base_compressor.rb', line 41

def algorithm_factory
  @algorithm_factory
end

#file_manager ⇒ Object (readonly)

Returns the value of attribute file_manager.



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# File 'lib/cabriolet/base_compressor.rb', line 41

def file_manager
  @file_manager
end

#io_system ⇒ Object (readonly)

Returns the value of attribute io_system.



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# File 'lib/cabriolet/base_compressor.rb', line 41

def io_system
  @io_system
end

Instance Method Details

#add_data(data, archive_path, **options) ⇒ FileEntry

Add file from memory to archive



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# File 'lib/cabriolet/base_compressor.rb', line 70

def add_data(data, archive_path, **options)
  @file_manager.add_data(data, archive_path, **options)
end

#add_file(source_path, archive_path = nil, **options) ⇒ FileEntry

Add file from disk to archive

Raises:



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# File 'lib/cabriolet/base_compressor.rb', line 60

def add_file(source_path, archive_path = nil, **options)
  @file_manager.add_file(source_path, archive_path, **options)
end

#generate(output_file, **options) ⇒ Integer

Generate archive (Template Method)

This method defines the compression workflow:

  1. Validate prerequisites

  2. Build format-specific structure

  3. Write to output file

  4. Post-generation hook

  5. Return bytes written

Subclasses customize via hook methods, not by overriding this method.

Raises:



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# File 'lib/cabriolet/base_compressor.rb', line 89

def generate(output_file, **options)
  validate_generation_prerequisites!(options)

  structure = build_structure(options)

  bytes_written = write_to_file(output_file, structure)

  post_generation_hook(output_file, structure, bytes_written)

  bytes_written
end