SimpleFileCache

SimpleFileCache writes a ruby object to a binary file so that it can be retrieved later from the disk rather than recomputed from scratch.

Usage

SimpleFileCache defines a single method #load_or_recompute that receives a file path and a block. If the file exists and is recent (e.g., last changed today), #load_or_recompute returns the existing file contents (read with Marshal#load). Otherwise, #load_or_recompute executes the block, saves its return value (with Marshal#dump) and returns the new data.

object = SimpleFileCache.load_or_recompute('example.dat') do
  # Code that performs a long, computationally expensive task 
  42
end

puts object # => 42

Configuration

Cache expiration policy

SimpleFileCache supports two different cache policies selected via the configuration variable cache_expiration_policy.

• :yesterday_or_earlier: the cache file will be regenerated it was not modified today (default)
• :max_age: the cache file will be regenerated if was not modified in the last N seconds (N is set via the cache_max_age_in_seconds configuration value)

Example:

SimpleFileCache.configure do |config|
  config.cache_expiration_policy = :max_age
  config.cache_max_age_in_seconds = 60
end

Cache files directory

By default, cache files will be saved in the current working directory ('.'). You can choose the caceh directory via the configuration variable :cache_dir_path:

Example:

SimpleFileCache.configure do |config|
  config.cache_dir_path = 'tmp/cache'
end

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/ricardo-jasinski/simple_file_cache.

License

The gem is available as open source under the terms of the Unlicense.