cache-base

Basic object cache with get, set, del, and has methods for node.js/javascript projects.

Please consider following this project's author, Jon Schlinkert, and consider starring the project to show your :heart: and support.

• Install
• Quickstart
• API
• Usage examples
• About

(TOC generated by verb using markdown-toc)

Install

Install with npm:

1$ npm install --save cache-base

Quickstart

1const CacheBase = require('cache-base');
2const app = new CacheBase();
3
4app.set('a.b', 'c');
5
6console.log(app.cache.a);    //=> { b: 'c' }
7console.log(app.cache.a.b);  //=> 'c'
8
9console.log(app.get('a'));   //=> { b: 'c' }
10console.log(app.get('a.b')); //=> 'c'

More usage examples below.

API

Params

• prop {String|Object}: (optional) Property name to use for the cache, or the object to initialize with.
• cache {Object}: (optional) An object to initialize with.

Example

1const app = new CacheBase();

.set

Assign value to key. Also emits set with the key and value.

Params

• key {String|Array}: The name of the property to set. Dot-notation may be used to set nested properties.
• value {any}
• returns {Object}: Returns the instance for chaining.

Events

• emits: set with key and value as arguments.

Example

1app.on('set', function(key, val) {
2  // do something when `set` is emitted
3});
4
5app.set('admin', true);
6
7// also takes an object or an array of objects
8app.set({ name: 'Brian' });
9app.set([{ foo: 'bar' }, { baz: 'quux' }]);
10console.log(app);
11//=> { name: 'Brian', foo: 'bar', baz: 'quux' }

.get

Return the value of key.

Params

• key {String|Array}: The name of the property to get. Dot-notation may be used to set nested properties.
• returns {any}: Returns the value of key

Events

• emits: get with key and value as arguments.

Example

1app.set('a.b.c', 'd');
2app.get('a.b');
3//=> { c: 'd' }

.prime

Create a property on the cache with the given value only if it doesn't already exist.

Params

• key {String}: Property name or object path notation.
• val {any}
• returns {Object}: Returns the instance for chaining.

Example

1console.log(app.cache); //=> {}
2app.set('one', { foo: 'bar' });
3app.prime('one', { a: 'b' });
4app.prime('two', { c: 'd' });
5console.log(app.cache.one); //=> { foo: 'bar' }
6console.log(app.cache.two); //=> { c: 'd' }

.default

Set a default value to be used when .get() is called and the value is not defined on the cache. Returns a value from the defaults when only a key is passed.

Params

• key {String|Array}: The name of the property to set. Dot-notation may be used to set nested properties.
• value {any}: (optional) The value to set on the defaults object.
• returns {Object}: Returns the instance for chaining.

Example

1app.set('foo', 'xxx');
2app.default('foo', 'one');
3app.default('bar', 'two');
4app.default('baz', 'three');
5app.set('baz', 'zzz');
6
7console.log(app.get('foo'));
8//=> 'xxx'
9
10console.log(app.get('bar'));
11//=> 'two'
12
13console.log(app.get('baz'));
14//=> 'zzz'
15
16console.log(app);
17// CacheBase {
18//   cache: { foo: 'xxx', bar: 'two', baz: 'zzz' },
19//   defaults: { foo: 'one', bar: 'two', baz: 'three' } }

.union

Set an array of unique values on cache key.

Params

• key {String|Array}: The name of the property to union. Dot-notation may be used to set nested properties.
• value {any}
• returns {Object}: Returns the instance for chaining.

Example

1app.union('a.b.c', 'foo');
2app.union('a.b.c', 'bar');
3app.union('a.b.c', ['bar', 'baz']);
4console.log(app.get('a'));
5//=> { b: { c: ['foo', 'bar', 'baz'] } }

.has

Return true if the value of property key is not undefined.

Params

• key {String|Array}: The name of the property to check. Dot-notation may be used to set nested properties.
• returns {Boolean}

Example

1app.set('foo', true);
2app.set('baz', null);
3app.set('bar', undefined);
4
5app.has('foo'); //=> true
6app.has('bar'); //=> true
7app.has('baz'); //=> false

.hasOwn

Returns true if the specified property is an own (not inherited) property. Similar to .has(), but returns true if the key exists, even if the value is undefined.

Params

• key {String}
• returns {Boolean}: Returns true if object key exists. Dot-notation may be used to set nested properties.

Example

1app.set('a.b.c', 'd');
2app.set('x', false);
3app.set('y', null);
4app.set('z', undefined);
5
6app.hasOwn('a');      //=> true
7app.hasOwn('b');      //=> true
8app.hasOwn('c');      //=> true
9app.hasOwn('a.b.c');  //=> true
10app.hasOwn('x');      //=> true
11app.hasOwn('y');      //=> true
12app.hasOwn('z');      //=> true
13app.hasOwn('lslsls'); //=> false

.del

Delete one or more properties from the instance.

Params

• key {String|Array}: The name of the property to delete. Dot-notation may be used to set nested properties.
• returns {Object}: Returns the instance for chaining.

Events

• emits: del with the key as the only argument.

Example

1// setup a listener to update a property with a default
2// value when it's deleted by the user
3app.on('del', key => app.set(key, app.default(key)));
4
5app.del(); // delete all properties on the cache
6// or
7app.del('foo');
8// or an array of keys
9app.del(['foo', 'bar']);

.clear

Reset the entire cache to an empty object. Note that this does not also clear the defaults object, since you can manually do cache.defaults = {} if you want to reset that object as well.

Example

1// clear "defaults" whenever the cache is cleared
2app.on('clear', key => (app.defaults = {}));
3app.clear();

.visit

Visit (or map visit) the specified method (key) over the properties in the given object or array.

Params

• key {String|Array}: The name of the method to visit.
• val {Object|Array}: The object or array to iterate over.
• returns {Object}: Returns the instance for chaining.

.keys

Gets an array of names of all enumerable properties on the cache.

Example

1const app = new CacheBase();
2app.set('user', true);
3app.set('admin', false);
4
5console.log(app.keys);
6//=> ['user', 'admin']

.size

Gets the length of keys.

Example

1const app = new CacheBase();
2app.set('user', true);
3app.set('admin', false);
4
5console.log(app.size);
6//=> 2

Usage examples

Create an instance of cache-base

1const app = new CacheBase();
2
3app.set('a', 'b');
4app.set('c.d', 'e');
5
6console.log(app.get('a'));
7//=> 'b'
8console.log(app.get('c'));
9//=> { d: 'e' }
10console.log(app);
11//=> CacheBase { a: 'b' }

Initialize with an object

1const app = new CacheBase({ a: 'b', c: { d: 'e' } });
2
3console.log(app.get('a'));
4//=> 'b'
5console.log(app.get('c'));
6//=> { d: 'e' }
7console.log(app.get('c.d'));
8//=> 'e'
9console.log(app);
10//=> CacheBase { cache: { a: 'b' } }

Inherit

1class MyApp extends CacheBase {}
2
3const app = new MyApp();
4app.set('a', 'b');
5app.set('c', 'd');
6
7console.log(app.get('a'));
8//=> 'b'
9
10console.log(app);
11//=> MyApp { cache: { a: 'b', c: 'd' } }

Custom namespace

Pass a string as the first value to the contructor to define a custom property name to use for the cache. By default values are stored on the cache property.

1const CacheBase = require('cache-base');
2const app = new CacheBase('data', { a: 'b' });
3app.set('c.d', 'e');
4
5// get values
6console.log(app.get('a'));
7//=> 'b'
8console.log(app.get('c'));
9//=> { d: 'e' }
10console.log(app.data);
11//=> { a: 'b', c: { d: 'e' } }
12console.log(app);
13//=> CacheBase { data: { a: 'b', c: { d: 'e' } } }

About

1$ npm install && npm test

1$ npm install -g verbose/verb#dev verb-generate-readme && verb

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• get-value: Use property paths like 'a.b.c' to get a nested value from an object. Even works… more | homepage
• has-value: Returns true if a value exists, false if empty. Works with deeply nested values using… more | homepage
• option-cache: Simple API for managing options in JavaScript applications. | homepage
• set-value: Create nested values and any intermediaries using dot notation ('a.b.c') paths. | homepage
• unset-value: Delete nested properties from an object using dot notation. | homepage

Contributors

Author

Jon Schlinkert

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• Twitter Profile

License

Copyright © 2018, Jon Schlinkert. Released under the MIT License.

This file was generated by verb-generate-readme, v0.6.0, on March 23, 2018.