foundationdb/recipes/ruby-recipes/micro_indirect.rb

84 lines
2.0 KiB
Ruby

#
# micro_indirect.rb
#
# This source file is part of the FoundationDB open source project
#
# Copyright 2013-2018 Apple Inc. and the FoundationDB project authors
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
require 'fdb'
FDB.api_version 300
class Workspace
def initialize(directory,db)
@dir = directory
@db = db
end
def enter()
@dir.create_or_open(@db,["new".encode('utf-8')])
end
def exit()
update(@db)
end
def update(db)
db.transact do |tr|
@dir.remove(tr,["current".encode('utf-8')])
@dir.move(tr,["new".encode('utf-8')],["current".encode('utf-8')])
end
end
def current()
@dir.create_or_open(@db,["current".encode('utf-8')])
end
end
def clear_subspace(db,subspace)
db.transact do |tr|
tr.clear_range_start_with(subspace.key)
end
end
def print_subspace(db,subspace)
db.transact do |tr|
tr.get_range(*subspace.range()) do |kv|
print subspace.unpack(kv.key)
puts kv.value
end
end
end
def smoke_test()
db = FDB.open()
working_dir = FDB::directory.create_or_open(db,["working".encode('utf-8')])
workspace = Workspace.new(working_dir,db)
current = workspace.current()
clear_subspace(db,current)
db[current[1]] = 'a'
db[current[2]] = 'b'
puts "contents:"
print_subspace(db,current)
newspace = workspace.enter()
clear_subspace(db,newspace)
db[newspace[3]] = 'c'
db[newspace[4]] = 'd'
workspace.exit()
puts "contents"
print_subspace(db,workspace.current())
end
smoke_test()