format_contexts.rb

require 'avro/registered_schema_decoder'


shared_context 'JSON format', format: :json do
  def parse(*args); JSON.parse(*args); end
  alias decode_key parse
  alias decode_value parse

  def fetch_int(object, name)
    object.fetch(name).fetch('int')
  end

  def fetch_string(object, name)
    object.fetch(name).fetch('string')
  end

  def fetch_bytes(object, name)
    unicode_encoded = object.fetch(name).fetch('bytes')
    # BW encodes e.g. 0xbeef as the JSON string "\u00be\u00ef"
    # i.e. each codepoint is actually a byte, and we just want to create the
    # binary byte array of those bytes.  This Array#pack incantation does it:
    unicode_encoded.codepoints.pack('C*')
  end

  def fetch_any(object, name)
    object.fetch(name).values.first
  end
end

shared_context 'Avro format', format: :avro do
  let(:decoder) do
    Avro::RegisteredSchemaDecoder.new(
      TEST_CLUSTER.schema_registry_url,
      logger: logger)
  end

  def decode_key(*args)
    decoder.decode_key(*args)
  end

  def decode_value(*args)
    decoder.decode_value(*args)
  end

  def fetch_entry(object, name)
    object.fetch(name)
  end
  alias fetch_int fetch_entry
  alias fetch_string fetch_entry
  alias fetch_bytes fetch_entry
  alias fetch_any fetch_entry
end