localforage-indexes

Plugin for localforage to work with indexes in indexedDb localForage.

Requirements

• localforage v1.4.0+

Installation

npm i localforage-indexes

API

createIndex

createIndex(indexName, keyPath[, options[, callback]])

Creates an index on the specified storage Supports promises and callbacks

Promise case:

localforage.createIndex('LF_INDEX', 'INDEXED_FIELD')
.then((index) => {
  // index created
})
.catch((err) => {
  //...
});

Callback case:

localforage.createIndex('LF_INDEX', 'INDEXED_FIELD', (err, index) => {
  // check error here
});

getIndex

getIndex(indexName[, callback])

Updates existing index on the specified storage Supports promises and callbacks

Promise case:

localforage.getIndex('LF_INDEX')
.then(() => {
  // index deleted
})
.catch((err) => {
  //...
});

Callback case:

localforage.getIndex('LF_INDEX', (err, index) => {
  // check error here
})

updateIndex

updateIndex(indexName, keyPath[, options[, callback]])

Updates existing index on the specified storage Used to change keyPath or options of an index Supports promises and callbacks

Promise case:

localforage.updateIndex('LF_INDEX', 'ANOTHER_INDEXED_FIELD')
.then((index) => {
  // index updated
})
.catch((err) => {
  //...
});

Callback case:

localforage.updateIndex('LF_INDEX', 'ANOTHER_INDEXED_FIELD', (err, index) => {
  // check error here
});

deleteIndex

deleteIndex(indexName[, callback])

Updates existing index on the specified storage Supports promises and callbacks

Promise case:

localforage.deleteIndex('LF_INDEX')
.then(() => {
  // index deleted
})
.catch((err) => {
  //...
});

Callback case:

localforage.deleteIndex('LF_INDEX', (err, index) => {
  // check error here
})

Methods' arguments

Arguments are the same as of vanilla indexedDb API Details

indexName - index name, must be unique for the store keyPath - path of the field that index is based upon, separated by dot: EXAMPLE.KEY.PATH options:

• multiEntry - will make an effect if keyPath resolves to an array. If true multiple index entry will be created for each array element, if false single instance is created. Default: false
• unique - if set to true removes duplicates from index. Default: false callback - Callback function. If one is provided method call won't return a promise. Instead a callback will be called when the indexedDB transaction is finished.

Usage

Warning: Firefox and Safari do not support usage of Promises with indexedDB's transactions

Any transaction passed through native promise will get destroyed. Firefox/Safari transactions can still be used with callbacks.

Intended to use only with indexedDb. Custom driver to be compatible with indexes must inherit from localforage's indexdDb(asyncStorage) driver.

import {extendPrototypeResult as localforage} from 'localforage-indexes';
 
localforage.createIndex('LF_INDEX', 'INDEXED_FIELD')
.then((index) => {
  // working with index...
})

Can be used with a single instance of localforage for each indexDb database.

import {extendPrototypeResult as localforage} from 'localforage-indexes';
 
var forage = localforage.createInstance({
  driver      : 'asyncStorage',
  name        : 'multiInstance',
  storeName   : 'multiInstanceStore'
});
 
var another_forage = localforage.createInstance({
  driver      : 'asyncStorage',
  name        : 'multiInstance',
  storeName   : 'anotherMultiInstanceStore'
});
 
forage.createIndex('newIndex', 'KEYPATH')
.then(() => {
  // will most likely cause an error because of conflicting db
  // versions
  another_forage.createIndex('anotherIndex');
});

Links

• GitHub
• NPM