Module: Eaternet::Util

Defined in:
lib/eaternet/util.rb

Class Method Summary collapse

Class Method Details

.download(source:, dest:) ⇒ File

Download a file from the network.

Parameters:

  • source (String) —

    the URL to retrieve

  • dest (String) —

    pathname in which to save the file

Returns:

  • (File) —

    the file



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# File 'lib/eaternet/util.rb', line 47

def self.download(source:, dest:)
  File.open(dest, 'wb') do |file|
    file << HTTParty.get(source, verify: false).body
  end
end

.download_and_cache(source:, dest:) ⇒ File

Download a file from the network, using a 12-hour cache.

Parameters:

  • source (String) —

    the URL to retrieve

  • dest (String) —

    pathname in which to save the file

Returns:

  • (File) —

    the file



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# File 'lib/eaternet/util.rb', line 34

def self.download_and_cache(source:, dest:)
  # download(source: source, dest: dest)
  cache_path = generate_cache_path(source)
  download(source: source, dest: cache_path) if expired? cache_path
  FileUtils.cp cache_path, dest
  File.open dest
end

.download_and_extract_zipfile(url) ⇒ String

Download a zip file and extract it into a temp directory.

Returns:

  • (String) —

    the directory path



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# File 'lib/eaternet/util.rb', line 11

def self.download_and_extract_zipfile(url)
  dir = make_temp_dir
  zip_path = File.join(dir, 'zip-file.zip')
  download_and_cache(source: url, dest: zip_path)
  extract_zipfile(path: zip_path, dest_dir: dir)
  dir
end

.expired?(cache_path) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/eaternet/util.rb', line 75

def self.expired?(cache_path)
  !File.exist?(cache_path) || file_age_in_days(cache_path) > 0.5
end

.extract_zipfile(path:, dest_dir:) ⇒ Object

Extract a Zip archive.

Parameters:

  • path (String) —

    the Zip file's location

  • dest_dir (String) —

    directory in which to perform the extraction

Returns:

  • nil



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# File 'lib/eaternet/util.rb', line 59

def self.extract_zipfile(path:, dest_dir:)
  open(path) do |zip_file|
    Zip::File.open(zip_file, 'rb') do |zip_data|
      zip_data.each do |entry|
        dest_path = File.join(dest_dir, entry.name)
        entry.extract(dest_path)
      end
    end
  end
end

.file_age_in_days(path) ⇒ Float

Returns:

  • (Float) 


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# File 'lib/eaternet/util.rb', line 71

def self.file_age_in_days(path)
  (Time.now - File.mtime(path)).to_i / 86_400.0
end

.generate_cache_path(url) ⇒ Object 



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# File 'lib/eaternet/util.rb', line 79

def self.generate_cache_path(url)
  cache_dir = prepare_cache_dir
  cache_key = Base64.strict_encode64(url)
  File.join(cache_dir, cache_key)
end

.make_temp_dir ⇒ String

Create a temporary directory which is automatically deleted when the program exits.

Returns:

  • (String) —

    the directory path



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# File 'lib/eaternet/util.rb', line 23

def self.make_temp_dir
  dir = Dir.mktmpdir
  at_exit { FileUtils.remove_entry dir }
  dir
end

.prepare_cache_dir ⇒ Object 



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# File 'lib/eaternet/util.rb', line 85

def self.prepare_cache_dir
  cache_dir = '/tmp/eaternet'
  `mkdir -p #{cache_dir}`
  cache_dir
end