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

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• Install
• Quickstart
• API
• Usage examples
• About

(TOC generated by verb using markdown-toc)

Install with npm:

$ npm install --save cache-base

const CacheBase = require('cache-base');
const app = new CacheBase();

app.set('a.b', 'c');

console.log(app.cache.a);    //=> { b: 'c' }
console.log(app.cache.a.b);  //=> 'c'

console.log(app.get('a'));   //=> { b: 'c' }
console.log(app.get('a.b')); //=> 'c'

More usage examples below.

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

const app = new CacheBase();

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

app.on('set', function(key, val) {
  // do something when `set` is emitted
});

app.set('admin', true);

// also takes an object or an array of objects
app.set({ name: 'Brian' });
app.set([{ foo: 'bar' }, { baz: 'quux' }]);
console.log(app);
//=> { name: 'Brian', foo: 'bar', baz: 'quux' }

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

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

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

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

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

app.set('foo', 'xxx');
app.default('foo', 'one');
app.default('bar', 'two');
app.default('baz', 'three');
app.set('baz', 'zzz');

console.log(app.get('foo'));
//=> 'xxx'

console.log(app.get('bar'));
//=> 'two'

console.log(app.get('baz'));
//=> 'zzz'

console.log(app);
// CacheBase {
//   cache: { foo: 'xxx', bar: 'two', baz: 'zzz' },
//   defaults: { foo: 'one', bar: 'two', baz: 'three' } }

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

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

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

app.set('foo', true);
app.set('baz', null);
app.set('bar', undefined);

app.has('foo'); //=> true
app.has('bar'); //=> true
app.has('baz'); //=> false

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

app.set('a.b.c', 'd');
app.set('x', false);
app.set('y', null);
app.set('z', undefined);

app.hasOwn('a');      //=> true
app.hasOwn('b');      //=> true
app.hasOwn('c');      //=> true
app.hasOwn('a.b.c');  //=> true
app.hasOwn('x');      //=> true
app.hasOwn('y');      //=> true
app.hasOwn('z');      //=> true
app.hasOwn('lslsls'); //=> false

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

// setup a listener to update a property with a default
// value when it's deleted by the user
app.on('del', key => app.set(key, app.default(key)));

app.del(); // delete all properties on the cache
// or
app.del('foo');
// or an array of keys
app.del(['foo', 'bar']);

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

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

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.

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

Example

const app = new CacheBase();
app.set('user', true);
app.set('admin', false);

console.log(app.keys);
//=> ['user', 'admin']

Gets the length of keys.

Example

const app = new CacheBase();
app.set('user', true);
app.set('admin', false);

console.log(app.size);
//=> 2

Create an instance of cache-base

const app = new CacheBase();

app.set('a', 'b');
app.set('c.d', 'e');

console.log(app.get('a'));
//=> 'b'
console.log(app.get('c'));
//=> { d: 'e' }
console.log(app);
//=> CacheBase { a: 'b' }

Initialize with an object

const app = new CacheBase({ a: 'b', c: { d: 'e' } });

console.log(app.get('a'));
//=> 'b'
console.log(app.get('c'));
//=> { d: 'e' }
console.log(app.get('c.d'));
//=> 'e'
console.log(app);
//=> CacheBase { cache: { a: 'b' } }

Inherit

class MyApp extends CacheBase {}

const app = new MyApp();
app.set('a', 'b');
app.set('c', 'd');

console.log(app.get('a'));
//=> 'b'

console.log(app);
//=> 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.

const CacheBase = require('cache-base');
const app = new CacheBase('data', { a: 'b' });
app.set('c.d', 'e');

// get values
console.log(app.get('a'));
//=> 'b'
console.log(app.get('c'));
//=> { d: 'e' }
console.log(app.data);
//=> { a: 'b', c: { d: 'e' } }
console.log(app);
//=> CacheBase { data: { a: 'b', c: { d: 'e' } } }

$ npm install && npm test

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

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• base-methods: base-methods is the foundation for creating modular, unit testable and highly pluggable node.js applications, starting… more | homepage
• 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

Jon Schlinkert

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

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