@openquantum/mongoose-cursor-pagination

mongoose-cursor-pagination

This small plugin makes it easy to use cursor-based pagination in your app, without changing the way you use queries in mongoose.

Installation

npm install @mother/mongoose-cursor-pagination --save

Node.js 10.x or higher is required.

Usage

In your schema:

import mongoose from 'mongoose'
import paginationPlugin from '@mother/mongoose-cursor-pagination'

const CommentSchema = new mongoose.Schema({
  date: { type: Date },
  body: { type: String },
  author: {
     firstName: { type: String },
     lastName: { type: String }
  }
})

CommentSchema.plugin(paginationPlugin)

In your application code:

const { results, pageInfo } = await Comment
   .find({})                 // Whatever filter you want
   .limit(30)                // Use limit and other Query options as you normally would
   .sort('author.lastName')  // Use sort as you would normally do
   .paginate(startCursor)    // startCursor optional
   .exec()                   // Required

results will be the results that you would expect from a normal mongoose find query

pageInfo will have two properties: hasNext and nextCursor

Be sure to index correctly. Note that this plugin always add _id to the sort key to ensure cursors are unique, so include that in your index as well. For example, say you are using the date field for pagination, then you would want to setup the index:

commentSchema.index({ date: -1, _id: -1 })

Plugin Options

You can optionally pass an options object to this plugin:

CommentSchema.plugin(paginationPlugin, {
   // If no limit is specified, and paginate() is being used,
   // what should the default limit be.
   defaultLimit: 100
})

Tests

Numerous tests are included in the tests directory, and can be run using the command npm test.

To Do

• Test against older versions of mongoose
• Support for search with pagination
• Support for aggregation with pagination
• Support for hasPrev and prevCursor
• Support exec calls that use callbacks instead of promises

License

MIT