Module: Store::Digest::Meta::LMDB

Includes:
Store::Digest::Meta, Trait::RootDir
Included in:
Driver::LMDB
Defined in:
lib/store/digest/meta/lmdb.rb,
lib/store/digest/meta/lmdb/v0.rb,
lib/store/digest/meta/lmdb/v1.rb

Overview

Symas LMDB Metadata driver.

Defined Under Namespace

Modules: V0, V1

Constant Summary collapse

PARAMS =

Return a list of objects matching the given criteria. The result set will be the intersection of all supplied parameters. :type, :charset, :encoding, and :language are treated like discrete sets, while the rest of the parameters are treated like ranges (two-element arrays). Single values will be coerced into arrays; single range values will be interpreted as an inclusive lower bound. To bound only at the top, use a two-element array with its first value nil, like so: size: [nil, 31337]. The sorting criteria are the symbols of the other parameters.

Returns:

  • (Array) —

    the list

%i[type charset encoding language
size ctime mtime ptime dtime].freeze

Instance Attribute Summary

Attributes included from Trait::RootDir

#dir, #umask

Instance Method Summary collapse

Instance Method Details

#algorithms ⇒ Array

Return the set of algorithms initialized in the database.

Returns:

  • (Array) —

    the algorithms



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# File 'lib/store/digest/meta/lmdb.rb', line 151

def algorithms
  @algorithms ||= lmdb.transaction? true do
    if ret = lmdb[:control]['algorithms']
      ret.strip.downcase.split(/\s*,+\s*/).map(&:to_sym)
    end
  end
end

#bytes ⇒ Integer

Return the number of bytes stored in the database (notwithstanding the database itself).

Returns:

  • (Integer) 


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# File 'lib/store/digest/meta/lmdb.rb', line 193

def bytes
  lmdb.transaction? true do
    if ret = lmdb[:control]['bytes']
      db_decode ret, :bytes
    end
  end
end

#deleted ⇒ Integer

Return the number of objects whose payloads are deleted but are still on record.

Returns:

  • (Integer) 


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# File 'lib/store/digest/meta/lmdb.rb', line 182

def deleted
  lmdb.transaction? true do
    if ret = lmdb[:control]['deleted']
      db_decode ret, :deleted
    end
  end
end

#list(type: nil, charset: nil, encoding: nil, language: nil, size: nil, ctime: nil, mtime: nil, ptime: nil, dtime: nil, sort: nil) ⇒ Object 



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# File 'lib/store/digest/meta/lmdb.rb', line 226

def list type: nil, charset: nil, encoding: nil, language: nil,
  size: nil, ctime: nil, mtime: nil, ptime: nil, dtime: nil, sort: nil
# coerce all the inputs
params = begin
           b  = binding
           ph = {}
           PARAMS.each do |key|
             val = b.local_variable_get key
             val = case val
                   when nil then []
                   when Time then [val]
                   when DateTime then [val.to_time]
                   when -> (v) { v.respond_to? :to_a } then val.to_a
                   else [val]
                   end
             ph[key] = val unless val.empty?
           end
           ph
         end
# find the smallest denominator
index = params.keys.map do |k|
  [k, lmdb[k].size]
end.sort { |a, b| a[1] <=> b[1] }.map(&:first).first
out = {}
lmdb.transaction? true do
  if index
    # warn params.inspect
    if INTS[index]
      index_get index, *params[index], range: true do |_, v|
        u = URI("ni:///#{primary};")
        u.digest = v
        out[u] ||= get u
      end
    else
      params[index].each do |val|
        index_get index, val do |_, v|
          u = URI("ni:///#{primary};")
          u.digest = v
          out[u] ||= get u
        end
      end
    end
    rest = params.keys - [index]
    unless rest.empty?
      out.select! do |_, obj|
        rest.map do |param|
          if val = obj.send(param)
            # warn "#{param} #{params[param]} <=> #{val}"
            if INTS[param]
              min, max = params[param]
              if min && max
                val >= min && val <= max
              elsif min
                val >= min
              elsif max
                val <= max
              end
            else
              params[param].include? val
            end
          else
            false
          end
        end.all?(true)
      end
    end
  else
    # if we aren't filtering at all we can just obtain everything
    lmdb[primary].cursor do |c|
      while rec = c.next
        u = URI("ni:///#{primary};")
        u.digest = rec.first
        out[u] ||= get u
      end
    end
  end
end

# now we sort
out.values
end

#lmdb ⇒ LMDB::Environment

Return the LMDB handle for the given process.

Returns:

  • (LMDB::Environment) 


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# File 'lib/store/digest/meta/lmdb.rb', line 130

def lmdb
  (@lmdb ||= {})[Process.pid] ||= ::LMDB.new dir, @lmdb_opts
end

#objects ⇒ Integer

Return the number of objects in the database.

Returns:

  • (Integer) 


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# File 'lib/store/digest/meta/lmdb.rb', line 171

def objects
  lmdb.transaction? true do
    if ret = lmdb[:control]['objects']
      db_decode ret, :objects
    end
  end
end

#primary ⇒ Symbol

Return the primary digest algorithm.

Returns:

  • (Symbol) —

    the primary algorithm



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# File 'lib/store/digest/meta/lmdb.rb', line 161

def primary
  @primary ||= lmdb.transaction? true do
    if ret = lmdb[:control]['primary']
      ret.strip.downcase.to_sym
    end
  end
end

#transaction(readonly: false, &block) ⇒ Object

Wrap the block in a transaction. Trying to start a read-write transaction (or do a write operation, as they are wrapped by transactions internally) within a read-only transaction will almost certainly break.

Parameters:

  • readonly (false, true) (defaults to: false) —

    whether the transaction is read-only

  • block (Proc) —

    the code to run.



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# File 'lib/store/digest/meta/lmdb.rb', line 142

def transaction readonly: false, &block
  lmdb.transaction?(readonly) do
    # we do not want to transmit the transaction
    block.call
  end
end