1 var path = require( 'path' );
2 var fs = require( 'graceful-fs' );
3 var utils = require( './utils' );
4 var del = require( './del' );
5 var writeJSON = utils.writeJSON;
9 * Load a cache identified by the given Id. If the element does not exists, then initialize an empty
10 * cache storage. If specified `cacheDir` will be used as the directory to persist the data to. If omitted
11 * then the cache module directory `./cache` will be used instead
14 * @param docId {String} the id of the cache, would also be used as the name of the file cache
15 * @param [cacheDir] {String} directory for the cache entry
17 load: function ( docId, cacheDir ) {
22 me._pathToFile = cacheDir ? path.resolve( cacheDir, docId ) : path.resolve( __dirname, './.cache/', docId );
24 if ( fs.existsSync( me._pathToFile ) ) {
25 me._persisted = utils.tryParse( me._pathToFile, { } );
30 * Load the cache from the provided file
32 * @param {String} pathToFile the path to the file containing the info for the cache
34 loadFile: function ( pathToFile ) {
36 var dir = path.dirname( pathToFile );
37 var fName = path.basename( pathToFile );
39 me.load( fName, dir );
43 * Returns the entire persisted object
48 return this._persisted;
52 return Object.keys( this._persisted );
55 * sets a key to a given value
57 * @param key {string} the key to set
58 * @param value {object} the value of the key. Could be any object that can be serialized with JSON.stringify
60 setKey: function ( key, value ) {
61 this._visited[ key ] = true;
62 this._persisted[ key ] = value;
65 * remove a given key from the cache
67 * @param key {String} the key to remove from the object
69 removeKey: function ( key ) {
70 delete this._visited[ key ]; // esfmt-ignore-line
71 delete this._persisted[ key ]; // esfmt-ignore-line
74 * Return the value of the provided key
76 * @param key {String} the name of the key to retrieve
77 * @returns {*} the value from the key
79 getKey: function ( key ) {
80 this._visited[ key ] = true;
81 return this._persisted[ key ];
85 * Remove keys that were not accessed/set since the
86 * last time the `prune` method was called.
94 var keys = Object.keys( me._visited );
96 // no keys visited for either get or set value
97 if ( keys.length === 0 ) {
101 keys.forEach( function ( key ) {
102 obj[ key ] = me._persisted[ key ];
110 * Save the state of the cache identified by the docId to disk
111 * as a JSON structure
112 * @param [noPrune=false] {Boolean} whether to remove from cache the non visited files
115 save: function ( noPrune ) {
118 (!noPrune) && me._prune();
119 writeJSON( me._pathToFile, me._persisted );
123 * remove the file where the cache is persisted
124 * @method removeCacheFile
125 * @return {Boolean} true or false if the file was successfully deleted
127 removeCacheFile: function () {
128 return del( this._pathToFile );
131 * Destroy the file cache and cache content.
134 destroy: function () {
139 me.removeCacheFile();
145 * Alias for create. Should be considered depreacted. Will be removed in next releases
148 * @param docId {String} the id of the cache, would also be used as the name of the file cache
149 * @param [cacheDir] {String} directory for the cache entry
150 * @returns {cache} cache instance
152 load: function ( docId, cacheDir ) {
153 return this.create( docId, cacheDir );
157 * Load a cache identified by the given Id. If the element does not exists, then initialize an empty
161 * @param docId {String} the id of the cache, would also be used as the name of the file cache
162 * @param [cacheDir] {String} directory for the cache entry
163 * @returns {cache} cache instance
165 create: function ( docId, cacheDir ) {
166 var obj = Object.create( cache );
167 obj.load( docId, cacheDir );
171 createFromFile: function ( filePath ) {
172 var obj = Object.create( cache );
173 obj.loadFile( filePath );
177 * Clear the cache identified by the given id. Caches stored in a different cache directory can be deleted directly
180 * @param docId {String} the id of the cache, would also be used as the name of the file cache
181 * @param cacheDir {String} the directory where the cache file was written
182 * @returns {Boolean} true if the cache folder was deleted. False otherwise
184 clearCacheById: function ( docId, cacheDir ) {
185 var filePath = cacheDir ? path.resolve( cacheDir, docId ) : path.resolve( __dirname, './.cache/', docId );
186 return del( filePath );
189 * Remove all cache stored in the cache directory
191 * @returns {Boolean} true if the cache folder was deleted. False otherwise
193 clearAll: function ( cacheDir ) {
194 var filePath = cacheDir ? path.resolve( cacheDir ) : path.resolve( __dirname, './.cache/' );
195 return del( filePath );