@seneca/cache

A Seneca.js in-memory caching plugin.

seneca-cache

Description

This module is a plugin for the Seneca framework. It provides a set of common caching actions (get, set etc.), backed by lru-cache. It also exposes some lru-cache specific actions (peek, has, keys, values, reset).

By moving cache operations into Seneca, you can change your cache implementation or business rules at a later point. For example, you might decide to send certain kinds of keys to a different cache mechanism, such as redis.

Install

npm install seneca
npm install seneca-cache

Quick example

This code snippet sets a value and then retrieves it.

var seneca = require('seneca')();
seneca.use('cache');

seneca.ready(function(err) {
  seneca.act({role: 'cache', cmd: 'set', key: 'k1', val: 'v1'}, function(err) {
    seneca.act({role: 'cache', cmd: 'get', key: 'k1'}, function(err, out) {
      console.log('value = ' + out)
    });
  });
});

Options

• micro.expiry : number 11111

Set plugin options when loading with:

seneca.use('cache', { name: value, ... })

Note: foo.bar in the list above means { foo: { bar: ... } }

Action Patterns

• role:cache,cmd:add
• role:cache,cmd:clear
• role:cache,cmd:decr
• role:cache,cmd:delete
• role:cache,cmd:get
• role:cache,cmd:incr
• role:cache,cmd:micro
• role:cache,cmd:micro,get:stats
• role:cache,cmd:set
• role:cache,get:native
• role:lrucache,cmd:has
• role:lrucache,cmd:keys
• role:lrucache,cmd:peek
• role:lrucache,cmd:reset
• role:lrucache,cmd:values

Action Descriptions

« role:cache,cmd:add »

No description provided.

« role:cache,cmd:clear »

No description provided.

« role:cache,cmd:decr »

No description provided.

« role:cache,cmd:delete »

No description provided.

« role:cache,cmd:get »

No description provided.

« role:cache,cmd:incr »

No description provided.

« role:cache,cmd:micro »

No description provided.

« role:cache,cmd:micro,get:stats »

No description provided.

« role:cache,cmd:set »

No description provided.

« role:cache,get:native »

No description provided.

« role:lrucache,cmd:has »

No description provided.

« role:lrucache,cmd:keys »

No description provided.

« role:lrucache,cmd:peek »

No description provided.

« role:lrucache,cmd:reset »

No description provided.

« role:lrucache,cmd:values »

No description provided.

Common Cache API

Seneca has a common caching API with the following actions:

• role:cache, cmd:set store a value - key and val arguments required
• role:cache, cmd:get retreive a value - key argument is required
• role:cache, cmd:add store a value, only if the key does not exist - key and val arguments required
• role:cache, cmd:delete delete a value - key argument is required, no error if key does not exist
• role:cache, cmd:incr increment a value - key and val (integer) arguments required
• role:cache, cmd:decr decrement a value - key and val (integer) arguments required

All caching plugins, including this one, implement this action API.

Options

You can use any of the options from the lru-cache module directly as options to this plugin:

seneca.use('cached', {
  lrucache: {
    max: 1000,
    maxAge: 1000 * 60 * 60,
    length: function(n) {return n.length}
  }
});

Contributing

The Senecajs org encourages open participation. If you feel you can help in any way, be it with documentation, examples, extra testing, or new features please get in touch.

Test

mocha test/cache.test.js

License

Copyright (c) 2014-2020, Richard Rodger, Seamus D'Arcy and other contributors. Licensed under MIT.