Class: IOStreams::Zip::Writer

Inherits:
Writer
  • Object
show all
Defined in:
lib/io_streams/zip/writer.rb

Instance Attribute Summary

Attributes inherited from Writer

#output_stream

Class Method Summary collapse

Methods inherited from Writer

#initialize, open

Constructor Details

This class inherits a constructor from IOStreams::Writer

Class Method Details

.file(file_name, zip_file_name: nil, entry_file_name: zip_file_name) ⇒ Object

When writing to a file, default the entry name within the zip to the file name without the ‘.zip` extension, unless an entry name was explicitly supplied.



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# File 'lib/io_streams/zip/writer.rb', line 6

def self.file(file_name, zip_file_name: nil, entry_file_name: zip_file_name, &)
  entry_file_name = file_name.to_s[0..-5] if entry_file_name.nil? && file_name.to_s =~ /\.zip\z/i

  super(file_name, entry_file_name: entry_file_name, &)
end

.stream(output_stream, zip_file_name: nil, entry_file_name: zip_file_name) ⇒ Object

Write a single file in Zip format to the supplied output stream

Parameters

output_stream [IO]
  Output stream to write to

entry_file_name: [String]
  Name of the file entry within the Zip file.
  Default: "file"

The stream supplied to the block only responds to #write

Note:

This writer uses `zip_kit` rather than `rubyzip` on purpose. `rubyzip`'s
`Zip::OutputStream` requires a seekable output: it seeks back to rewrite each
entry's local header with the CRC and sizes once the entry is finished. That
means it cannot write directly to a non-seekable destination (S3, SFTP, HTTP,
a socket); the output would first have to be spooled to a temporary file and
then copied across. `zip_kit` streams to non-seekable outputs by emitting
data descriptors instead, so we can write straight to the output stream and
avoid the temp file round-trip.



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# File 'lib/io_streams/zip/writer.rb', line 33

def self.stream(output_stream, zip_file_name: nil, entry_file_name: zip_file_name)
  entry_file_name ||= "file"

  Utils.load_soft_dependency("zip_kit", "Zip") unless defined?(ZipKit::Streamer)

  result = nil
  ZipKit::Streamer.open(output_stream) do |zip|
    zip.write_deflated_file(entry_file_name) { |io| result = yield(io) }
  end
  result
end