83 lines
2.0 KiB
Ruby
83 lines
2.0 KiB
Ruby
require 'mongo/types/objectid'
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require 'mongo/util/byte_buffer'
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require 'mongo/util/ordered_hash'
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module XGen
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module Mongo
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module GridFS
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# A chunk stores a portion of GridStore data.
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#
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# TODO: user-defined chunk size
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class Chunk
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DEFAULT_CHUNK_SIZE = 1024 * 256
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attr_reader :object_id, :chunk_number
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attr_accessor :data
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def initialize(file, mongo_object={})
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@file = file
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@object_id = mongo_object['_id'] || XGen::Mongo::Driver::ObjectID.new
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@chunk_number = mongo_object['n'] || 0
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@data = ByteBuffer.new
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case mongo_object['data']
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when String
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mongo_object['data'].each_byte { |b| @data.put(b) }
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when ByteBuffer
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@data.put_array(mongo_object['data'].to_a)
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when Array
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@data.put_array(mongo_object['data'])
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when nil
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else
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raise "illegal chunk format; data is #{mongo_object['data'] ? (' ' + mongo_object['data'].class.name) : 'nil'}"
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end
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@data.rewind
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end
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def pos; @data.position; end
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def pos=(pos); @data.position = pos; end
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def eof?; !@data.more?; end
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def size; @data.size; end
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alias_method :length, :size
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# Erase all data after current position.
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def truncate
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if @data.position < @data.length
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curr_data = @data
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@data = ByteBuffer.new
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@data.put_array(curr_data.to_a[0...curr_data.position])
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end
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end
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def getc
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@data.more? ? @data.get : nil
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end
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def putc(byte)
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@data.put(byte)
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end
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def save
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coll = @file.chunk_collection
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coll.remove({'_id' => @object_id})
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coll.insert(to_mongo_object)
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end
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def to_mongo_object
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h = OrderedHash.new
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h['_id'] = @object_id
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h['files_id'] = @file.files_id
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h['n'] = @chunk_number
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h['data'] = data
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h
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end
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end
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end
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end
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end
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