hyperdb-stage v0.0.4

hyperdb-stage

A staging area for hyperdb.

This enables you to interact with the stage as if it is the actual hyperdb instance. Put, delete, get, create a stream of data, or whatever, exactly as you would normally. However any changes you make to the stage will not effect the actual db until you commit them.

hyperdb-stage is not multi writer enabled.

Installation

npm install hyperdb-stage

Usage

A super simple example:

const hyperdb = require('hyperdb')
const createStage = require('hyperdb-stage')
const ram = require('random-access-memory')

const db = hyperdb(() => ram())

db.put('a', 'value', () => {
  // simply wrap any db in stage to create a staging area
  const tmp = createStage(db)
  tmp.put('b', 'next value', () => {
    // b is not yet available in the db until you commit
    tmp.commit(() => {
      // b is now committed added to the db
    })
  })
})

API

Stage has mostly the same api as hyperdb.

Stage specific functions

In addition to hyperdb there are these special stage methods.

stage = createStage(db)

Takes a hyperdb instance and returns a staging area.

stage.commit(callback)

This commits staged changes to the hyperdb.

Note: hyperdb-stage commits the state of the staging area, not its history. Changes are committed in key hash order not in the order that they were added.

Callback is fired once all changes have been committed.

stage.revert()

Destroy all staged changes.

Unsupported Hyperdb methods

The Staging area is not intended to be replicated or shared. It is a temporary in memory database for staging changes before committing them to your db instance.

As such the following methods are unsupported.

• db.key
• db.discoveryKey
• db.local
• db.on()
• db.version()
• db.checkout(version)
• db.authorize(key, callback)
• db.authorized(key, callback)
• db.replicate(options)

Note: You can still access these methods via staging.db or on the original hyperdb instance.