hold-this v1.2.2

Hold This

A simple key-value store that uses SQLite as the backend. It is designed to be used in a single-threaded synchronous environment.

Getting Started

npm install --save hold-this

Use in-memory store

import hold from 'hold-this'

const holder = hold()
holder.set('accounts', 'account-123:user-123:name', 'Alice')
holder.set('accounts', 'account-123:user-456:name', 'Bob')

console.log(holder.get('accounts', 'account-123:*:name'))
// => [['account-123:user-123:name', 'Alice'], ['account-123:user-456:name', 'Bob']]

Other Examples

File based store

Pass an object with a key location and a path to a file. This will be the filepath that hold-this utilizes to write to disk.

import hold from 'hold-this'

const holder = holder({ location: './holder.sqlite' })
holder.set('accounts', 'account-123:user-123:name', 'Alice')
holder.set('accounts', 'account-123:user-456:name', 'Bob')

console.log(holder.get('accounts', 'account-123:*:name'))
// => [['account-123:user-123:name', 'Alice'], ['account-123:user-456:name', 'Bob']]

File based store defaults to using WAL for performance purposes. This can be disabled by setting { enableWAL: false} when creating the instance.

!CAUTION This will severely decrease write performance for File based storage.

import hold from 'hold-this'

const holder = holder({ location: './holder.sqlite', enableWAL: false })

!TIP You can benchmark by running npm run test:bench

Performed on Macbook Pro M1 with 16 GB Memory

Bind Topic / Shorthand

Calling .bind('myTopic') on your hold-this instance, will return a modified instance that has topic already defined on set/get methods.

import hold from 'hold-this'

const holder = holder().bind('accounts')
holder.set('account-123:user-123:name', 'Alice')
holder.get('account-123:user-456:name', 'Bob')

console.log(holder.get('account-123:*:name'))
// => [['account-123:user-123:name', 'Alice'], ['account-123:user-456:name', 'Bob']]

Serialization

When passing the value with .set, if the value is not a string, the data will be serialized with serialize-javascript and then stored. Passing an options object like { isJSON: true }, with a proper JSON object, will signal to the serializer to use a faster mechanism.

import hold from 'hold-this'

const holder = holder().bind('accounts')
holder.set('account-123:user-123:name', { firstName: 'Alice' }, { isJSON: true })
holder.get('account-123:user-456:name', 'Bob')

console.log(holder.get('account-123:*:name'))
// => [['account-123:user-123:name', { firstName: 'Alice' }], ['account-123:user-456:name', 'Bob']]

TTTL / Expiring Records

When setting a record, specifying in a options object { ttl: 1000 } will set a date in the future where the record will no longer be retrievable. Note: TTL value is set in milliseconds.

import hold from 'hold-this'

const holder = hold()
holder.set('accounts', 'account-123:user-123:name', 'Alice', { ttl: 1000 })
holder.set('accounts', 'account-123:user-456:name', 'Bob', { ttl: 0 })

console.log(holder.get('accounts', 'account-123:*:name'))
// => [['account-123:user-123:name', 'Alice']]

After a period of time, it is recommended to clean out expired records from the store. This can be achieved by calling .clean() on the instance which will remove all expired records from all topics. If a topic parameter is provided .clean('myTopic'), only this topic's expired records will be removed.

import hold from 'hold-this'

const holder = hold()
holder.set('accounts', 'account-123:user-123:name', 'Alice', { ttl:  })

holder.clean()