58 lines
1.4 KiB
Ruby
58 lines
1.4 KiB
Ruby
#
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# micro_blob.rb
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#
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# This source file is part of the FoundationDB open source project
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#
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# Copyright 2013-2018 Apple Inc. and the FoundationDB project authors
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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#
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require 'fdb'
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FDB.api_version 300
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@db = FDB.open()
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def clear_subspace(db,subspace)
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db.transact do |tr|
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tr.clear_range_start_with(subspace.key)
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end
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end
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CHUNK_SIZE = 5
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@blob = FDB::Subspace.new(['B'])
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def write_blob(db,data)
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return if data.length == 0
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db.transact do |tr|
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chunks = (0...data.length).step(CHUNK_SIZE).map { |x| [x, x + CHUNK_SIZE] }
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chunks.each do |chunk|
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start, stop = *chunk
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tr[@blob[start]] = data[start...stop]
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end
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end
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end
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def read_blob(db)
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db.transact do |tr|
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value = ''
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tr.get_range( *@blob.range() ) do |kv|
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puts kv.value
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value += kv.value
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end
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value
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end
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end
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clear_subspace(@db,@blob)
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write_blob(@db,'ABCDEFGHIJKLMNOPQRSTUVWXYZ')
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puts read_blob(@db) |