Class: JekyllImgFlow::FilenameGenerator

Inherits:
Object
  • Object
show all
Defined in:
lib/jekyll-imgflow/filename_generator.rb

Overview

Generates unique filenames for processed images Compatible with Jekyll Picture Tag format

Constant Summary collapse

VECTOR_FORMATS =

Generate filename for processed image (Jekyll Picture Tag compatible) Formats that are valid for output (raster only). SVG and other vector formats are input-only — image providers always produce raster output (webp, avif, jpg, png).

Returns:

  • (String) —

    Generated filename (without path)

%w[svg].freeze

Instance Method Summary collapse

Instance Method Details

#file_digest(original_path) ⇒ String

Get file digest for manifest tracking

Parameters:

  • original_path (String) —

    Path to original image

Returns:

  • (String) —

    SHA256 digest of file



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# File 'lib/jekyll-imgflow/filename_generator.rb', line 35

def file_digest(original_path)
  Digest::SHA256.file(original_path).hexdigest
end

#generate_filename(original_name, operations) ⇒ Object 



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# File 'lib/jekyll-imgflow/filename_generator.rb', line 18

def generate_filename(original_name, operations)
  base_name = File.basename(original_name, ".*")
  width = operations[:width]
  format = operations[:format] || File.extname(original_name).delete(".")
  # Vector formats (e.g. SVG) are input-only — never use them as
  # output format. Fall back to jpg (universal <img> fallback).
  format = "jpg" if VECTOR_FORMATS.include?(format.to_s.downcase)

  # Generate hash using Jekyll Picture Tag approach
  hash = generate_jpt_hash(original_name, operations)

  "#{base_name}-#{width}-#{hash}.#{format}"
end

#parse_filename(filename) ⇒ Hash

Parse filename to extract width and hash

Parameters:

  • filename (String) —

    Generated filename

Returns:

  • (Hash) —

    Parsed components width, hash, format



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# File 'lib/jekyll-imgflow/filename_generator.rb', line 42

def parse_filename(filename)
  # Parse pattern: basename-width-hash.format - simple string operations
  # Find last dot to separate format
  last_dot = filename.rindex(".")
  return {} unless last_dot

  format = filename[(last_dot + 1)..]
  name_part = filename[0...last_dot]

  # Find last dash to separate hash
  last_dash = name_part.rindex("-")
  return {} unless last_dash

  hash = name_part[(last_dash + 1)..]
  name_without_hash = name_part[0...last_dash]

  # Find second-to-last dash to separate width
  second_last_dash = name_without_hash.rindex("-")
  return {} unless second_last_dash

  width_str = name_without_hash[(second_last_dash + 1)..]
  base_name = name_without_hash[0...second_last_dash]

  # Validate components
  return {} unless hash.match?(/^[a-f0-9]+$/)
  return {} unless width_str.match?(/^\d+$/)

  {
    base_name: base_name,
    width: width_str.to_i,
    hash: hash,
    format: format
  }
end