Decode Compressed Response

When the :decode_compressed_response option is set to a truthy value, VCR will decompress "gzip" and "deflate" response bodies before recording. This ensures that these interactions become readable and editable after being serialized.

This option should be avoided if the actual decompression of response bodies is part of the functionality of the library or app being tested.

Background ()

Given a file named "decompress.rb" with:

require 'zlib'
require 'stringio'

$server = start_sinatra_app do
  get('/') {
    content = 'The quick brown fox jumps over the lazy dog'
    io = StringIO.new

    writer = Zlib::GzipWriter.new(io)
    writer << content
    writer.close

    headers['Content-Encoding'] = 'gzip'
    io.string
  }
end

require 'vcr'

VCR.configure do |c|
  c.cassette_library_dir = 'cassettes'
  c.hook_into :webmock
  c.default_cassette_options = { :serialize_with => :syck }
end

The option is not set by default

When I append to file "decompress.rb":

VCR.use_cassette(:decompress) do
  Net::HTTP.start('localhost', $server.port) do |http|
    http.get('/', 'accept-encoding' => 'identity')
  end
end

And I run ruby decompress.rb

Then the file "cassettes/decompress.yml" should contain a YAML fragment like:

Content-Encoding:
- gzip

The option is enabled

When I append to file "decompress.rb":

VCR.use_cassette(:decompress, :decode_compressed_response => true) do
  Net::HTTP.start('localhost', $server.port) do |http|
    http.get('/', 'accept-encoding' => 'identity')
  end
end

And I run ruby decompress.rb

Then the file "cassettes/decompress.yml" should contain a YAML fragment like:

Content-Length:
- '43'

And the file "cassettes/decompress.yml" should contain:

string: The quick brown fox jumps over the lazy dog

Last updated