amahi/platform

# utilities to manage a temporary cache of downloaded or generated files

class TempCache

    class << self
        # expire files that have not been accessed in a while
        def expire_unused_files
            Dir.glob(File.join(HDA_TMP_DIR, "**/**")) do |f|
                begin
                    if File.exists?(f) && File.atime(f) < 3.months.ago
                        FileUtils.rm_rf(f)
                    end
                rescue
                    # ignore errors, because it's theoretically possible that
                    # there might be files in-flight and the exists? is true
                    # yet the atime fails, or even the rm
                end
            end
        end

        # return a unique name for creating a file
        def unique_filename(base)
            expire_unused_files
            File.join(HDA_TMP_DIR, "#{base}-%d.%d" % [$$, rand(9999)])
        end
    end
end