ruby/red-arrow/example/read-stream.rb

#!/usr/bin/env ruby
#
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# to you under the Apache License, Version 2.0 (the
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#
#   http://www.apache.org/licenses/LICENSE-2.0
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require "arrow"

Arrow::MemoryMappedInputStream.open("/tmp/stream.arrow") do |input|
  reader = Arrow::RecordBatchStreamReader.new(input)
  fields = reader.schema.fields
  reader.each_with_index do |record_batch, i|
    puts("=" * 40)
    puts("record-batch[#{i}]:")
    fields.each do |field|
      field_name = field.name
      values = record_batch.collect do |record|
        record[field_name]
      end
      puts("  #{field_name}: #{values.inspect}")
    end
  end
end