dynongo-pager

Easy paging for DynamoDB with dynongo

Install

$ npm install --save dynongo-pager

Note: this package has a peer dependency on [email protected] or higher.

Usage

const db = require('dynongo');
const pager = require('dynongo-pager');

// Connect with the database
db.connect();

const Document = db.table('Document');

pager(Document, {user: '1'}, {
	limit: 2,
	elementIndex: () => ['user', 'date']
}).then(page1 => {
	console.log(page1);
	/**
	 * {
	 *   items: [
	 *     { user: '1', date: '2017-07-28T18:33:12Z', src: 'foo.pdf' },
	 *     { user: '1', date: '2017-07-29T12:18:56Z', src: 'bar.pdf' }
	 *   ],
	 *   paging: {
	 *     after: 'eyJ1c2VyIjoiMSIsImRhdGUiOiIyMDE3LTA3LTI5VDEyOjE4OjU2WiJ9'
	 *   }
	 * }
	 */

	return pager(Document, {user: 1}, {
		limit: 2,
		after: page1.paging.after,
		elementIndex: () => ['user', 'date']
	});
}).then(page2 => {
	console.log(page2);
	/**
	 * {
	 *   items: [
	 *     { user: '1', date: '2017-07-30T06:26:11Z', src: 'unicorn.pdf' },
	 *     { user: '1', date: '2017-07-31T08:04:10Z', src: 'rainbow.pdf' }
	 *   ],
	 *   paging: {
	 *     before: 'eyJ1c2VyIjoiMSIsImRhdGUiOiIyMDE3LTA3LTMwVDA2OjI2OjExWiJ9',
	 *     after: 'eyJ1c2VyIjoiMSIsImRhdGUiOiIyMDE3LTA3LTMxVDA4OjA0OjEwWiJ9'
	 *   }
	 * }
	 */
});

In the example above, we query the Documents table to retrieve all the documents of the user with ID 1. The user property is the partion key, and the date property is the sort key.

The before value is the base64 encoded representation of the index (partition key and sort key) of the first element in the items list. The after value is the base64 encode representation of the index of the last element in the items list.

API

pager(table, index, [options])

table

Type: Table

Dynongo table.

index

Type: Object

Partition key.

options

elementIndex

Required Type: function

Function that should return the properties being part of the index. The function accepts an argument being the name of the index that's being used to query the database.

limit

Type: number

Limit of items per page. If not provided, the page will retrieve as many items as possible which is 1MB in size.

after

Type: string

Token to retrieve the next page.

before

Type: string

Token to retrieve the previous page.

from

Type: string number boolean

Lower boundary of the sort key.

to

Type: string number boolean

Upper boundary of the sort key.

indexName

Type: string

Name of the index to use.

select

Type: string

Space separated list of the values you want to retrieve.

where

Type: object

Filter object.

sort

Type: number Options: 1 -1

Sort the values ascending (1) or descending (-1).

Related

• dynongo - MongoDB like syntax for DynamoDB

License

MIT © Sam Verschueren