Class: ODBA::Cache

Inherits:
Object show all
Includes:
DRb::DRbUndumped, Singleton
Defined in:
lib/odba/cache.rb

Constant Summary collapse

CLEANER_PRIORITY =

:nodoc:

0
CLEANING_INTERVAL =

:nodoc:

5
LOCK_FILE =

File lock exclusive control between processes, not threads, to create safely a new odba_id Sometimes several update jobs (processes) to the same database at the same time

"/tmp/lockfile"
COUNT_FILE = 
"/tmp/count"
@@receiver_name = 
:@receiver

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize ⇒ Cache

:nodoc:



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# File 'lib/odba/cache.rb', line 17

def initialize # :nodoc:
  if self.class::CLEANING_INTERVAL > 0
    start_cleaner
  end
  @retire_age = 300
  @receiver = nil
  @cache_mutex = Mutex.new
  @deferred_indices = []
  @fetched = {}
  @prefetched = {}
  @clean_prefetched = false
  @cleaner_offset = 0
  @prefetched_offset = 0
  @cleaner_step = 500
  @loading_stats = {}
  @peers = []
  @file_lock = false
  @debug ||= false # Setting @debug to true makes two unit test fail!
end

Instance Attribute Details

#cleaner_step ⇒ Object

Returns the value of attribute cleaner_step.



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# File 'lib/odba/cache.rb', line 16

def cleaner_step
  @cleaner_step
end

#debug ⇒ Object

Returns the value of attribute debug.



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# File 'lib/odba/cache.rb', line 16

def debug
  @debug
end

#destroy_age ⇒ Object

Returns the value of attribute destroy_age.



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# File 'lib/odba/cache.rb', line 16

def destroy_age
  @destroy_age
end

#file_lock ⇒ Object

Returns the value of attribute file_lock.



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# File 'lib/odba/cache.rb', line 16

def file_lock
  @file_lock
end

#retire_age ⇒ Object

Returns the value of attribute retire_age.



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# File 'lib/odba/cache.rb', line 16

def retire_age
  @retire_age
end

Instance Method Details

#_clean(retire_time, holder, offset) ⇒ Object

:nodoc:



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# File 'lib/odba/cache.rb', line 101

def _clean(retire_time, holder, offset) # :nodoc:
  if offset > holder.size
    offset = 0
  end
  counter = 0
  cutoff = offset + @cleaner_step
  @cache_mutex.synchronize {
    holder.each_value { |value|
      counter += 1
      if counter > offset && value.odba_old?(retire_time)
        value.odba_retire && @cleaned += 1
      end
      return cutoff if counter > cutoff
    }
  }
  cutoff
# every once in a while we'll get a 'hash modified during iteration'-Error.
# not to worry, we'll just try again later.
rescue
  offset
end

#bulk_fetch(bulk_fetch_ids, odba_caller) ⇒ Object

Returns all objects designated by bulk_fetch_ids and registers odba_caller for each of them. Objects which are not yet loaded are loaded from ODBA#storage.



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# File 'lib/odba/cache.rb', line 40

def bulk_fetch(bulk_fetch_ids, odba_caller)
  instances = []
  loaded_ids = []
  bulk_fetch_ids.each { |id|
    if (entry = fetch_cache_entry(id))
      entry.odba_add_reference(odba_caller)
      instances.push(entry.odba_object)
      loaded_ids.push(id)
    end
  }
  bulk_fetch_ids -= loaded_ids
  unless bulk_fetch_ids.empty?
    rows = ODBA.storage.bulk_restore(bulk_fetch_ids)
    instances += bulk_restore(rows, odba_caller)
  end
  instances
end

#bulk_restore(rows, odba_caller = nil) ⇒ Object

:nodoc:



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# File 'lib/odba/cache.rb', line 58

def bulk_restore(rows, odba_caller = nil) # :nodoc:
  if ::Kernel::caller.size > 1000
    # with size > 30 it crashed in parse_aips_download
    # with size > 50 parse_aips_download was okay
    # if nothing it crashed with a stack of > 8000
    raise OdbaError
  end
  retrieved_objects = []
  rows.each { |row|
    obj_id = row.at(0)
    dump = row.at(1)
    odba_obj = fetch_or_restore(obj_id, dump, odba_caller)
    retrieved_objects.push(odba_obj)
  }
  retrieved_objects
end

#clean ⇒ Object

:nodoc:



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# File 'lib/odba/cache.rb', line 75

def clean # :nodoc:
  now = Time.now
  start = Time.now if @debug
  @cleaned = 0
  if @debug
    puts "starting cleaning cycle"
    $stdout.flush
  end
  retire_horizon = now - @retire_age
  @cleaner_offset = _clean(retire_horizon, @fetched, @cleaner_offset)
  if @clean_prefetched
    @prefetched_offset = _clean(retire_horizon, @prefetched,
      @prefetched_offset)
  end
  if @debug
    puts "cleaned: #{@cleaned} objects in #{Time.now - start} seconds"
    puts "remaining objects in @fetched:    #{@fetched.size}"
    puts "remaining objects in @prefetched: #{@prefetched.size}"
    mbytes = File.read("/proc/#{$$}/stat").split(" ").at(22).to_i / (2**20)
    GC.start
    puts "remaining objects in ObjectSpace: #{ObjectSpace.each_object {}}"
    puts "memory-usage:                     #{mbytes}MB"
    $stdout.flush
  end
end

#clean_prefetched(flag = true) ⇒ Object

overrides the ODBA_PREFETCH constant and @odba_prefetch instance variable in Persistable. Use this if a secondary client is more memory-bound than performance-bound.



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# File 'lib/odba/cache.rb', line 126

def clean_prefetched(flag = true)
  if (@clean_prefetched = flag)
    clean
  end
end

#clear ⇒ Object

:nodoc:



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# File 'lib/odba/cache.rb', line 132

def clear # :nodoc:
  @fetched.clear
  @prefetched.clear
end

#count(klass) ⇒ Object

Get number of instances of a class



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# File 'lib/odba/cache.rb', line 237

def count(klass)
  ODBA.storage.extent_count(klass)
end

#create_deferred_indices(drop_existing = false) ⇒ Object

Creates or recreates automatically defined indices



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# File 'lib/odba/cache.rb', line 138

def create_deferred_indices(drop_existing = false)
  @deferred_indices.each { |definition|
    name = definition.index_name
    if drop_existing && indices.include?(name)
      drop_index(name)
    end
    unless indices.include?(name)
      index = create_index(definition)
      if index.target_klass.respond_to?(:odba_extent)
        index.fill(index.target_klass.odba_extent)
      end
    end
  }
end

#create_index(index_definition, origin_module = Object) ⇒ Object

Creates a new index according to IndexDefinition



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# File 'lib/odba/cache.rb', line 154

def create_index(index_definition, origin_module = Object)
  transaction {
    klass = if index_definition.fulltext
      FulltextIndex
    elsif index_definition.resolve_search_term.is_a?(Hash)
      ConditionIndex
    else
      Index
    end
    index = klass.new(index_definition, origin_module)
    indices.store(index_definition.index_name, index)
    indices.odba_store_unsaved
    index
  }
end

#delete(odba_object) ⇒ Object

Permanently deletes object from the database and deconnects all connected Persistables



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# File 'lib/odba/cache.rb', line 172

def delete(odba_object)
  odba_id = odba_object.odba_id
  name = odba_object.odba_name
  odba_object.odba_notify_observers(:delete, odba_id, odba_object.object_id)
  rows = ODBA.storage.retrieve_connected_objects(odba_id)
  rows.each { |row|
    id = row.first
    # Self-Referencing objects don't have to be resaved
    begin
      if (connected_object = fetch(id, nil))
        connected_object.odba_cut_connection(odba_object)
        connected_object.odba_isolated_store
      end
    rescue OdbaError
      warn "OdbaError ### deleting #{odba_object.class}:#{odba_id}"
      warn "          ### while looking for connected object #{id}"
    end
  }
  delete_cache_entry(odba_id)
  delete_cache_entry(name)
  ODBA.storage.delete_persistable(odba_id)
  delete_index_element(odba_object)
  odba_object
end

#delete_cache_entry(key) ⇒ Object 



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# File 'lib/odba/cache.rb', line 197

def delete_cache_entry(key)
  @cache_mutex.synchronize {
    @fetched.delete(key)
    @prefetched.delete(key)
  }
end

#delete_index_element(odba_object) ⇒ Object

:nodoc:



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# File 'lib/odba/cache.rb', line 204

def delete_index_element(odba_object) # :nodoc:
  odba_object.class
  indices.each_value { |index|
    index.delete(odba_object)
  }
end

#drop_index(index_name) ⇒ Object

Permanently deletes the index named index_name



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# File 'lib/odba/cache.rb', line 212

def drop_index(index_name)
  transaction {
    ODBA.storage.drop_index(index_name)
    delete(indices[index_name])
  }
end

#drop_indices ⇒ Object

:nodoc:



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# File 'lib/odba/cache.rb', line 219

def drop_indices # :nodoc:
  keys = indices.keys
  keys.each { |key|
    drop_index(key)
  }
end

#ensure_index_deferred(index_definition) ⇒ Object

Queue an index for creation by #setup



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# File 'lib/odba/cache.rb', line 227

def ensure_index_deferred(index_definition)
  @deferred_indices.push(index_definition)
end

#extent(klass, odba_caller = nil) ⇒ Object

Get all instances of a class (- a limited extent)



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# File 'lib/odba/cache.rb', line 232

def extent(klass, odba_caller = nil)
  bulk_fetch(ODBA.storage.extent_ids(klass), odba_caller)
end

#fetch(odba_id, odba_caller = nil) ⇒ Object

Fetch a Persistable identified by odba_id. Registers odba_caller with the CacheEntry. Loads the Persistable if it is not already loaded.



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# File 'lib/odba/cache.rb', line 243

def fetch(odba_id, odba_caller = nil)
  fetch_or_do(odba_id, odba_caller) {
    load_object(odba_id, odba_caller)
  }
end

#fetch_cache_entry(odba_id_or_name) ⇒ Object

:nodoc:



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# File 'lib/odba/cache.rb', line 249

def fetch_cache_entry(odba_id_or_name) # :nodoc:
  @prefetched[odba_id_or_name] || @fetched[odba_id_or_name]
end

#fetch_collection(odba_obj) ⇒ Object

:nodoc:



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# File 'lib/odba/cache.rb', line 253

def fetch_collection(odba_obj) # :nodoc:
  collection = []
  bulk_fetch_ids = []
  rows = ODBA.storage.restore_collection(odba_obj.odba_id)
  return collection if rows.empty?
  idx = 0
  rows.each { |row|
    key = row[0].is_a?(Integer) ? row[0] : ODBA.marshaller.load(row[0])
    value = row[1].is_a?(Integer) ? row[1] : ODBA.marshaller.load(row[1])
    idx += 1
    item = nil
    if [key, value].any? { |item| item.instance_variable_get(@@receiver_name) }
      odba_id = odba_obj.odba_id
      warn "stub for #{item.class}:#{item.odba_id} was saved with receiver in collection of #{odba_obj.class}:#{odba_id}"
      warn "repair: remove [#{odba_id}, #{row[0]}, #{row[1].length}]"
      ODBA.storage.collection_remove(odba_id, row[0])
      key = key.odba_isolated_stub
      key_dump = ODBA.marshaller.dump(key)
      value = value.odba_isolated_stub
      value_dump = ODBA.marshaller.dump(value)
      warn "repair: insert [#{odba_id}, #{key_dump}, #{value_dump.length}]"
      ODBA.storage.collection_store(odba_id, key_dump, value_dump)
    end
    bulk_fetch_ids.push(key.odba_id)
    bulk_fetch_ids.push(value.odba_id)
    collection.push([key, value])
  }
  bulk_fetch_ids.compact!
  bulk_fetch_ids.uniq!
  bulk_fetch(bulk_fetch_ids, odba_obj)
  collection.each { |pair|
    pair.collect! { |item|
      if item.is_a?(ODBA::Stub)
        ## don't fetch: that may result in a conflict when storing.
        # fetch(item.odba_id, odba_obj)
        item.odba_container = odba_obj
        item
      elsif (ce = fetch_cache_entry(item.odba_id))
        warn "collection loaded unstubbed object: #{item.odba_id}"
        ce.odba_add_reference(odba_obj)
        ce.odba_object
      else
        item
      end
    }
  }
  collection
end

#fetch_collection_element(odba_id, key) ⇒ Object

:nodoc:



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# File 'lib/odba/cache.rb', line 302

def fetch_collection_element(odba_id, key) # :nodoc:
  key_dump = ODBA.marshaller.dump(key.odba_isolated_stub)
  ## for backward-compatibility and robustness we only attempt
  ## to load if there was a dump stored in the collection table
  if (dump = ODBA.storage.collection_fetch(odba_id, key_dump))
    item = ODBA.marshaller.load(dump)
    if item.is_a?(ODBA::Stub)
      fetch(item.odba_id)
    elsif item.is_a?(ODBA::Persistable)
      warn "collection_element was unstubbed object: #{item.odba_id}"
      fetch_or_restore(item.odba_id, dump, nil)
    else
      item
    end
  end
end

#fetch_named(name, odba_caller, &block) ⇒ Object

:nodoc:



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# File 'lib/odba/cache.rb', line 319

def fetch_named(name, odba_caller, &block) # :nodoc:
  fetch_or_do(name, odba_caller) {
    dump = ODBA.storage.restore_named(name)
    if dump.nil?
      odba_obj = block.call
      odba_obj.odba_name = name
      odba_obj.odba_store(name)
      odba_obj
    else
      fetch_or_restore(name, dump, odba_caller)
    end
  }
end

#fetch_or_do(obj_id, odba_caller, &block) ⇒ Object

:nodoc:



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# File 'lib/odba/cache.rb', line 333

def fetch_or_do(obj_id, odba_caller, &block) # :nodoc:
  if (cache_entry = fetch_cache_entry(obj_id)) && cache_entry._odba_object
    cache_entry.odba_add_reference(odba_caller)
    cache_entry.odba_object
  else
    block.call
  end
end

#fetch_or_restore(odba_id, dump, odba_caller) ⇒ Object

:nodoc:



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# File 'lib/odba/cache.rb', line 342

def fetch_or_restore(odba_id, dump, odba_caller) # :nodoc:
  fetch_or_do(odba_id, odba_caller) {
    odba_obj, _ = restore(dump)
    @cache_mutex.synchronize {
      fetch_or_do(odba_id, odba_caller) {
        cache_entry = CacheEntry.new(odba_obj)
        cache_entry.odba_add_reference(odba_caller)
        hash = odba_obj.odba_prefetch? ? @prefetched : @fetched
        name = odba_obj.odba_name
        hash.store(odba_obj.odba_id, cache_entry)
        if name
          hash.store(name, cache_entry)
        end
        odba_obj
      }
    }
  }
end

#fill_index(index_name, targets) ⇒ Object 



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# File 'lib/odba/cache.rb', line 361

def fill_index(index_name, targets)
  indices[index_name].fill(targets)
end

#include?(odba_id) ⇒ Boolean

Checks wether the object identified by odba_id has been loaded.

Returns:

  • (Boolean) 


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# File 'lib/odba/cache.rb', line 366

def include?(odba_id)
  @fetched.include?(odba_id) || @prefetched.include?(odba_id)
end

#index_keys(index_name, length = nil) ⇒ Object 



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# File 'lib/odba/cache.rb', line 370

def index_keys(index_name, length = nil)
  index = indices.fetch(index_name)
  index.keys(length)
end

#index_matches(index_name, substring, limit = nil, offset = 0) ⇒ Object 



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# File 'lib/odba/cache.rb', line 375

def index_matches(index_name, substring, limit = nil, offset = 0)
  index = indices.fetch(index_name)
  index.matches substring, limit, offset
end

#indices ⇒ Object

Returns a Hash-table containing all stored indices.



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# File 'lib/odba/cache.rb', line 381

def indices
  @indices ||= fetch_named("__cache_server_indices__", self) {
    {}
  }
end

#invalidate(odba_id) ⇒ Object 



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# File 'lib/odba/cache.rb', line 387

def invalidate(odba_id)
  ## when finalizers are run, no other threads will be scheduled,
  #  therefore we don't need to @cache_mutex.synchronize
  @fetched.delete odba_id
  @prefetched.delete odba_id
end

#invalidate!(*odba_ids) ⇒ Object 



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# File 'lib/odba/cache.rb', line 394

def invalidate!(*odba_ids)
  odba_ids.each do |odba_id|
    if entry = fetch_cache_entry(odba_id)
      entry.odba_retire force: true
    end
    invalidate odba_id
  end
end

#lock(dbname) ⇒ Object 



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# File 'lib/odba/cache.rb', line 406

def lock(dbname)
  lock_file = LOCK_FILE + "." + dbname
  open(lock_file, "a") do |st|
    st.flock(File::LOCK_EX)
    yield
    st.flock(File::LOCK_UN)
  end
end

#new_id(dbname, odba_storage) ⇒ Object 



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# File 'lib/odba/cache.rb', line 415

def new_id(dbname, odba_storage)
  count_file = COUNT_FILE + "." + dbname
  count = nil
  lock(dbname) do
    unless File.exist?(count_file)
      open(count_file, "w") do |out|
        out.print odba_storage.max_id
      end
    end
    count = File.read(count_file).to_i
    count += 1
    open(count_file, "w") do |out|
      out.print count
    end
    odba_storage.update_max_id(count)
  end
  count
end

#next_id ⇒ Object

Returns the next valid odba_id



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# File 'lib/odba/cache.rb', line 435

def next_id
  if @file_lock
    dbname = ODBA.storage.instance_variable_get(:@dbi).dbi_args.first.split(":").last
    id = new_id(dbname, ODBA.storage)
  else
    id = ODBA.storage.next_id
  end
  @peers.each do |peer|
    peer.reserve_next_id id
  rescue DRb::DRbError
    # A peer we cannot reach must not stop the allocation. Note the
    # explicit class: a bare rescue here also swallowed the
    # OdbaDuplicateIdError a peer raises when the id is already taken,
    # so the retry below could never run and both processes kept the
    # same id. Whichever wrote last overwrote the other's row in
    # `object`, and every reference to it then resolved to a foreign
    # object.
  end
  id
rescue OdbaDuplicateIdError
  retry
end

#prefetch ⇒ Object

Use this to load all prefetchable Persistables from the db at once



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# File 'lib/odba/cache.rb', line 459

def prefetch
  bulk_restore(ODBA.storage.restore_prefetchable)
end

#print_stats ⇒ Object

prints loading statistics to $stdout



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# File 'lib/odba/cache.rb', line 464

def print_stats
  fmh = " %-20s | %10s | %5s | %6s | %6s | %6s | %-20s\n"
  fmt = " %-20s | %10.3f | %5i | %6.3f | %6.3f | %6.3f | %s\n"
  head = sprintf(fmh,
    "class", "total", "count", "min", "max", "avg", "callers")
  line = "-" * head.length
  puts line
  print head
  puts line
  @loading_stats.sort_by { |key, val|
    val[:total_time]
  }.reverse_each { |key, val|
    key = key.to_s
    if key.length > 20
      key = key[-20, 20]
    end
    avg = val[:total_time] / val[:count]
    printf(fmt, key, val[:total_time], val[:count],
      val[:times].min, val[:times].max, avg,
      val[:callers].join(","))
  }
  puts line
  $stdout.flush
end

#register_peer(peer) ⇒ Object

Register a peer that has access to the same DB backend



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# File 'lib/odba/cache.rb', line 490

def register_peer peer
  @peers.push(peer).uniq!
end

#reserve_next_id(id) ⇒ Object

Reserve an id with all registered peers



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# File 'lib/odba/cache.rb', line 495

def reserve_next_id id
  ODBA.storage.reserve_next_id id
end

#reset_stats ⇒ Object

Clears the loading statistics



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# File 'lib/odba/cache.rb', line 500

def reset_stats
  @loading_stats.clear
end

#retrieve_from_index(index_name, search_term, meta = nil) ⇒ Object

Find objects in an index



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# File 'lib/odba/cache.rb', line 505

def retrieve_from_index(index_name, search_term, meta = nil)
  index = indices.fetch(index_name)
  ids = index.fetch_ids(search_term, meta)
  if meta.respond_to?(:error_limit) && (limit = meta.error_limit) \
    && (size = ids.size) > limit.to_i
    error = OdbaResultLimitError.new
    error.limit = limit
    error.size = size
    error.index = index_name
    error.search_term = search_term
    error.meta = meta
    raise error
  end
  bulk_fetch(ids, nil)
end

#setup ⇒ Object

Create necessary DB-Structure / other storage-setup



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# File 'lib/odba/cache.rb', line 522

def setup
  ODBA.storage.setup
  indices.each_key { |index_name|
    ODBA.storage.ensure_target_id_index(index_name)
  }
  create_deferred_indices
  nil
end

#size ⇒ Object

Returns the total number of cached objects



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# File 'lib/odba/cache.rb', line 532

def size
  @prefetched.size + @fetched.size
end

#start_cleaner ⇒ Object

:nodoc:



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# File 'lib/odba/cache.rb', line 536

def start_cleaner # :nodoc:
  @cleaner = Thread.new {
    Thread.current.priority = self.class::CLEANER_PRIORITY
    loop {
      sleep(self.class::CLEANING_INTERVAL)
      begin
        clean
      rescue => e
        puts e
        puts e.backtrace
      end
    }
  }
end

#store(object) ⇒ Object

Store a Persistable object in the database



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# File 'lib/odba/cache.rb', line 552

def store(object)
  odba_id = object.odba_id
  name = object.odba_name
  object.odba_notify_observers(:store, odba_id, object.object_id)
  if (ids = Thread.current[:txids])
    ids.unshift([odba_id, name])
  end
  ## get target_ids before anything else
  target_ids = object.odba_target_ids
  store_collection_elements(object)
  prefetchable = object.odba_prefetch?
  dump = object.odba_isolated_dump
  ODBA.storage.store(odba_id, dump, name, prefetchable, object.class)
  store_object_connections(odba_id, target_ids)
  update_references(target_ids, object)
  object = store_cache_entry(odba_id, object, name)
  update_indices(object)
  @peers.each do |peer|
    peer.invalidate! odba_id
  rescue
    DRb::DRbError
  end
  object
end

#store_cache_entry(odba_id, object, name = nil) ⇒ Object

:nodoc:



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# File 'lib/odba/cache.rb', line 577

def store_cache_entry(odba_id, object, name = nil) # :nodoc:
  @cache_mutex.synchronize {
    if cache_entry = fetch_cache_entry(odba_id)
      cache_entry.update object
    else
      hash = object.odba_prefetch? ? @prefetched : @fetched
      cache_entry = CacheEntry.new(object)
      hash.store(odba_id, cache_entry)
      unless name.nil?
        hash.store(name, cache_entry)
      end
    end
    cache_entry.odba_object
  }
end

#store_collection_elements(odba_obj) ⇒ Object

:nodoc:



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# File 'lib/odba/cache.rb', line 593

def store_collection_elements(odba_obj) # :nodoc:
  odba_id = odba_obj.odba_id
  collection = odba_obj.odba_collection.collect { |key, value|
    [ODBA.marshaller.dump(key.odba_isolated_stub),
      ODBA.marshaller.dump(value.odba_isolated_stub)]
  }
  old_collection = ODBA.storage.restore_collection(odba_id).collect { |row|
    [row[0], row [1]]
  }
  changes = (old_collection - collection).each { |key_dump, _|
    ODBA.storage.collection_remove(odba_id, key_dump)
  }.size
  changes + (collection - old_collection).each { |key_dump, value_dump|
    ODBA.storage.collection_store(odba_id, key_dump, value_dump)
  }.size
end

#store_object_connections(odba_id, target_ids) ⇒ Object

:nodoc:



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# File 'lib/odba/cache.rb', line 610

def store_object_connections(odba_id, target_ids) # :nodoc:
  ODBA.storage.ensure_object_connections(odba_id, target_ids)
end

#transaction(&block) ⇒ Object

Executes the block in a transaction. If the transaction fails, all affected Persistable objects are reloaded from the db (which by then has also performed a rollback). Rollback is quite inefficient at this time.



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# File 'lib/odba/cache.rb', line 617

def transaction(&block)
  Thread.current[:txids] = []
  ODBA.storage.transaction(&block)
rescue Exception => excp
  transaction_rollback
  raise excp
ensure
  Thread.current[:txids] = nil
end

#transaction_rollback ⇒ Object

:nodoc:



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# File 'lib/odba/cache.rb', line 627

def transaction_rollback # :nodoc:
  if (ids = Thread.current[:txids])
    ids.each { |id, name|
      if (entry = fetch_cache_entry(id))
        if (dump = ODBA.storage.restore(id))
          odba_obj, _ = restore(dump)
          entry.odba_replace!(odba_obj)
        else
          entry.odba_cut_connections!
          delete_cache_entry(id)
          delete_cache_entry(name)
        end
      end
    }
  end
end

#unregister_peer(peer) ⇒ Object

Unregister a peer



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# File 'lib/odba/cache.rb', line 645

def unregister_peer peer
  @peers.delete peer
end

#update_indices(odba_object) ⇒ Object

:nodoc:



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# File 'lib/odba/cache.rb', line 649

def update_indices(odba_object) # :nodoc:
  if odba_object.odba_indexable?
    indices.each { |index_name, index|
      index.update(odba_object)
    }
  end
end

#update_references(target_ids, object) ⇒ Object

:nodoc:



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# File 'lib/odba/cache.rb', line 657

def update_references(target_ids, object) # :nodoc:
  target_ids.each { |odba_id|
    if (entry = fetch_cache_entry(odba_id))
      entry.odba_add_reference(object)
    end
  }
end