Class: Grape::Util::Cache

Inherits:

Object

• Object
• Grape::Util::Cache

Extended by:

Forwardable

Includes:

Singleton

Defined in:

lib/grape/util/cache.rb

Overview

Base class for the lazily-filled lookup caches (coercers, dry-types, path parts, ...). Subclasses assign a default-block Hash to @cache in their initialize.

Lookups are synchronized: caches are written at API definition time (a params block runs when the class body is evaluated), which is not covered by the compile-time Grape::API::Instance::LOCK and can happen concurrently — e.g. parallel eager loading, or two threads autoloading different API files. A Monitor (reentrant) rather than a Mutex, because a cache miss may re-enter the same cache: building a multiple-type coercer through Types::CoercerCache builds its member coercers through Types.build_coercer, which lands in the same cache.

Direct Known Subclasses

ContentTypes::LookupCache, ContentTypes::MimeTypesCache, DryTypes::ParamsCache, DryTypes::StrictCache, Namespace::JoinedSpaceCache, Router::BaseRoute::CaptureIndexCache, Router::Pattern::Path::PartsCache, Router::Pattern::PatternCache, Validations::ParamsDocumentation::TypeCache, Validations::Types::CoercerCache

Instance Attribute Summary

• #cache ⇒ Object readonly

  Returns the value of attribute cache.

Instance Method Summary

• #[](key) ⇒ Object
• #initialize ⇒ Cache constructor

  A new instance of Cache.

Constructor Details

#initialize ⇒ Cache

Returns a new instance of Cache.

# File 'lib/grape/util/cache.rb', line 22

def initialize
  @monitor = Monitor.new
end

Instance Attribute Details

#cache ⇒ Object (readonly)

Returns the value of attribute cache.

# File 'lib/grape/util/cache.rb', line 20

def cache
  @cache
end

Instance Method Details

#[](key) ⇒ Object

# File 'lib/grape/util/cache.rb', line 26

def [](key)
  @monitor.synchronize { @cache[key] }
end