Class: Sass::CacheStore

Inherits:
Object
  • Object
show all
Defined in:
lib/sass/cache_store.rb

Overview

An abstract base class for backends for the Sass cache. Any key-value store can act as such a backend; it just needs to implement the #_store and #_retrieve methods.

To use a cache store with Sass, use the :cache_store option.

Direct Known Subclasses

FileCacheStore, InMemoryCacheStore

Instance Method Summary collapse

Instance Method Details

#_retrieve(key, version, sha) ⇒ String, NilClass

Retrieved cached contents. Must be implemented by all subclasses.

Note: if the key exists but the sha or version have changed, then the key may be deleted by the cache store, if it wants to do so.

Parameters:

  • key (String) —

    The key to retrieve

  • version (String) —

    The current sass version. Cached contents must not be retrieved across different versions of sass.

  • sha (String) —

    The sha of the sass source. Cached contents must not be retrieved if the sha has changed.

Returns:

  • (String) —

    The contents that were previously stored.

  • (NilClass) —

    when the cache key is not found or the version or sha have changed.



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# File 'lib/sass/cache_store.rb', line 40

def _retrieve(key, version, sha)
  raise "#{self.class} must implement #_retrieve."
end

#_store(key, version, sha, contents)

Store cached contents for later retrieval Must be implemented by all CacheStore subclasses

Note: cache contents contain binary data.

Parameters:

  • key (String) —

    The key to store the contents under

  • version (String) —

    The current sass version. Cached contents must not be retrieved across different versions of sass.

  • sha (String) —

    The sha of the sass source. Cached contents must not be retrieved if the sha has changed.

  • contents (String) —

    The contents to store.



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# File 'lib/sass/cache_store.rb', line 23

def _store(key, version, sha, contents)
  raise "#{self.class} must implement #_store."
end

#key(sass_dirname, sass_basename)

Return the key for the sass file.

The (sass_dirname, sass_basename) pair should uniquely identify the Sass document, but otherwise there are no restrictions on their content.

Parameters:

  • sass_dirname (String) —

    The fully-expanded location of the Sass file. This corresponds to the directory name on a filesystem.

  • sass_basename (String) —

    The name of the Sass file that is being referenced. This corresponds to the basename on a filesystem.



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# File 'lib/sass/cache_store.rb', line 82

def key(sass_dirname, sass_basename)
  dir = Digest::SHA1.hexdigest(sass_dirname)
  filename = "#{sass_basename}c"
  "#{dir}/#{filename}"
end

#retrieve(key, sha) ⇒ Sass::Tree::RootNode

Retrieve a Tree::RootNode.

Parameters:

  • key (String) —

    The key the root element was stored under.

  • sha (String) —

    The checksum of the root element's content.

Returns:



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# File 'lib/sass/cache_store.rb', line 63

def retrieve(key, sha)
  contents = _retrieve(key, Sass::VERSION, sha)
  Haml::Util.load(contents) if contents
rescue EOFError, TypeError, ArgumentError => e
  raise
  Haml::Util.haml_warn "Warning. Error encountered while reading cache #{path_to(key)}: #{e}"
end

#store(key, sha, root)

Store a Tree::RootNode.

Parameters:

  • key (String) —

    The key to store it under.

  • sha (String) —

    The checksum for the contents that are being stored.

  • root (Sass::Tree::RootNode) —

    The root of the tree to be stored.



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# File 'lib/sass/cache_store.rb', line 49

def store(key, sha, root)
  orig_options = root.options
  begin
    _store(key, Sass::VERSION, sha, Haml::Util.dump(root))
  ensure
    root.options = orig_options
  end
end