2.7 KiB
2.7 KiB
flat-cache
A stupidly simple key/value storage using files to persist the data
install
npm i --save flat-cache
Usage
var flatCache = require('flat-cache')
// loads the cache, if one does not exists for the given
// Id a new one will be prepared to be created
var cache = flatCache.load('cacheId');
// sets a key on the cache
cache.setKey('key', { foo: 'var' });
// get a key from the cache
cache.getKey('key') // { foo: 'var' }
// fetch the entire persisted object
cache.all() // { 'key': { foo: 'var' } }
// remove a key
cache.removeKey('key'); // removes a key from the cache
// save it to disk
cache.save(); // very important, if you don't save no changes will be persisted.
// cache.save( true /* noPrune */) // can be used to prevent the removal of non visited keys
// loads the cache from a given directory, if one does
// not exists for the given Id a new one will be prepared to be created
var cache = flatCache.load('cacheId', path.resolve('./path/to/folder'));
// The following methods are useful to clear the cache
// delete a given cache
flatCache.clearCacheById('cacheId') // removes the cacheId document if one exists.
// delete all cache
flatCache.clearAll(); // remove the cache directory
Motivation for this module
I needed a super simple and dumb in-memory cache with optional disk persistance in order to make
a script that will beutify files with esformatter
only execute on the files that were changed since the last run.
To make that possible we need to store the fileSize
and modificationTime
of the files. So a simple key/value
storage was needed and Bam! this module was born.
Important notes
- If no directory is especified when the
load
method is called, a folder named.cache
will be created inside the module directory whencache.save
is called. If you're committing yournode_modules
to any vcs, you might want to ignore the default.cache
folder, or specify a custom directory. - The values set on the keys of the cache should be
stringify-able
ones, meaning no circular references - All the changes to the cache state are done to memory
- I could have used a timer or
Object.observe
to deliver the changes to disk, but I wanted to keep this module intentionally dumb and simple - Non visited keys are removed when
cache.save()
is called. If this is not desired, you can passtrue
to the save call like:cache.save( true /* noPrune */ )
.
License
MIT