class ActiveSupport::Cache::FileStore
A cache store implementation which stores everything on the filesystem.
FileStore implements the Strategy::LocalCache strategy which implements an in-memory cache inside of a block.
Constants
- DIR_FORMATTER
- EXCLUDED_DIRS
- FILENAME_MAX_SIZE
- FILEPATH_MAX_SIZE
- GITKEEP_FILES
Attributes
Public Class Methods
# File lib/active_support/cache/file_store.rb, line 24 def initialize(cache_path, options = nil) super(options) @cache_path = cache_path.to_s end
Public Instance Methods
Preemptively iterates through all stored keys and removes the ones which have expired.
# File lib/active_support/cache/file_store.rb, line 39 def cleanup(options = nil) options = merged_options(options) search_dir(cache_path) do |fname| entry = read_entry(fname, options) delete_entry(fname, options) if entry && entry.expired? end end
Deletes all items from the cache. In this case it deletes all the entries
in the specified file store directory except for .keep or .gitkeep. Be
careful which directory is specified in your config file when using
FileStore
because everything in that directory will be
deleted.
# File lib/active_support/cache/file_store.rb, line 32 def clear(options = nil) root_dirs = exclude_from(cache_path, EXCLUDED_DIRS + GITKEEP_FILES) FileUtils.rm_r(root_dirs.collect { |f| File.join(cache_path, f) }) rescue Errno::ENOENT end
Decrements an already existing integer value that is stored in the cache. If the key is not found nothing is done.
# File lib/active_support/cache/file_store.rb, line 55 def decrement(name, amount = 1, options = nil) modify_value(name, -amount, options) end
# File lib/active_support/cache/file_store.rb, line 59 def delete_matched(matcher, options = nil) options = merged_options(options) instrument(:delete_matched, matcher.inspect) do matcher = key_matcher(matcher, options) search_dir(cache_path) do |path| key = file_path_key(path) delete_entry(path, options) if key.match(matcher) end end end
Increments an already existing integer value that is stored in the cache. If the key is not found nothing is done.
# File lib/active_support/cache/file_store.rb, line 49 def increment(name, amount = 1, options = nil) modify_value(name, amount, options) end
Private Instance Methods
Delete empty directories in the cache.
# File lib/active_support/cache/file_store.rb, line 148 def delete_empty_directories(dir) return if File.realpath(dir) == File.realpath(cache_path) if exclude_from(dir, EXCLUDED_DIRS).empty? Dir.delete(dir) rescue nil delete_empty_directories(File.dirname(dir)) end end
# File lib/active_support/cache/file_store.rb, line 88 def delete_entry(key, options) if File.exist?(key) begin File.delete(key) delete_empty_directories(File.dirname(key)) true rescue => e # Just in case the error was caused by another process deleting the file first. raise e if File.exist?(key) false end end end
Make sure a file path's directories exist.
# File lib/active_support/cache/file_store.rb, line 157 def ensure_cache_path(path) FileUtils.makedirs(path) unless File.exist?(path) end
Exclude entries from source directory
# File lib/active_support/cache/file_store.rb, line 191 def exclude_from(source, excludes) Dir.entries(source).reject { |f| excludes.include?(f) } end
Translate a file path into a key.
# File lib/active_support/cache/file_store.rb, line 142 def file_path_key(path) fname = path[cache_path.to_s.size..-1].split(File::SEPARATOR, 4).last URI.decode_www_form_component(fname, Encoding::UTF_8) end
Lock a file for a block so only one process can modify it at a time.
# File lib/active_support/cache/file_store.rb, line 103 def lock_file(file_name, &block) if File.exist?(file_name) File.open(file_name, "r+") do |f| begin f.flock File::LOCK_EX yield ensure f.flock File::LOCK_UN end end else yield end end
Modifies the amount of an already existing integer value that is stored in the cache. If the key is not found nothing is done.
# File lib/active_support/cache/file_store.rb, line 176 def modify_value(name, amount, options) file_name = normalize_key(name, options) lock_file(file_name) do options = merged_options(options) if num = read(name, options) num = num.to_i + amount write(name, num, options) num end end end
Translate a key into a file path.
# File lib/active_support/cache/file_store.rb, line 119 def normalize_key(key, options) key = super fname = URI.encode_www_form_component(key) if fname.size > FILEPATH_MAX_SIZE fname = ActiveSupport::Digest.hexdigest(key) end hash = Zlib.adler32(fname) hash, dir_1 = hash.divmod(0x1000) dir_2 = hash.modulo(0x1000) fname_paths = [] # Make sure file name doesn't exceed file system limits. begin fname_paths << fname[0, FILENAME_MAX_SIZE] fname = fname[FILENAME_MAX_SIZE..-1] end until fname.blank? File.join(cache_path, DIR_FORMATTER % dir_1, DIR_FORMATTER % dir_2, *fname_paths) end
# File lib/active_support/cache/file_store.rb, line 72 def read_entry(key, options) if File.exist?(key) File.open(key) { |f| Marshal.load(f) } end rescue => e logger.error("FileStoreError (#{e}): #{e.message}") if logger nil end
# File lib/active_support/cache/file_store.rb, line 161 def search_dir(dir, &callback) return if !File.exist?(dir) Dir.foreach(dir) do |d| next if EXCLUDED_DIRS.include?(d) name = File.join(dir, d) if File.directory?(name) search_dir(name, &callback) else callback.call name end end end
# File lib/active_support/cache/file_store.rb, line 81 def write_entry(key, entry, options) return false if options[:unless_exist] && File.exist?(key) ensure_cache_path(File.dirname(key)) File.atomic_write(key, cache_path) { |f| Marshal.dump(entry, f) } true end