MongoDb / Mongoose pagination done right

An utility function to work with ranged pagination, way faster than using skip().

Install

$ npm install mongoose-range-paginate

Example

var paginate = require('mongoose-range-paginate')

...

// use any field name in your model, in this case we sort by 'timestamp'
var sortKey = 'timestamp'

// DESC because starts with a minus '-timestamp'
var sort = '-' + sortKey

function getQuery() {
  return Posts.find()
    .where({ tags: { $in ['foo', 'bar'] } })
}

paginate(getQuery(), { sort: sort, limit: 50 }).exec(function (err, docs) {
  // first 50 docs ready

  paginate(getQuery(), {
    sort: sort,
    startId: docs[49]._id,
    startKey: docs[49][sortKey],
    limit: 10
  }).exec(function (err, docs) {
    // next 10 docs ready
  })
})

KoaJS Example

var paginate = require('mongoose-range-paginate')

...

router.get('/list', function *() {
  var query = Posts.find()
    .where({ tags: { $in ['koajs', 'yield'] } })
    .where({ published: true })
    .where({ author: 'Kilian' })

  // force sorting, newest first
  this.query.sort = '-timestamp'

  // pass limit, startId and startKey on query string
  paginate(query, this.query)

  this.type = 'json'
  this.body = query.lean().stream().pipe(stringify())
})

Signature

paginate(query, opts)

opts

• sort (String) mongoose sort criteria, supports ASC and DESC with the "-" prefix.
• limit (Number: defaults to 10) limits the number of documents.
• startId (String) id of the last document of your last result set, next result set will start with the document next to this.
• startKey (String) the value of the sort field of the last document of your result set, next result set will start with the document next to this.

Test suite

Be sure you have MongoDb up and running locally, then run

$ npm test

License

This software is released under the MIT license cited below.

Copyright (c) 2014 Kilian Ciuffolo, [email protected]. All Rights Reserved.

Permission is hereby granted, free of charge, to any person
obtaining a copy of this software and associated documentation
files (the 'Software'), to deal in the Software without
restriction, including without limitation the rights to use,
copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following
conditions:

The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.