docs.sheetjs.com/docz/docs/03-demos/07-data/25-mongodb.md

title	pagination_prev	pagination_next	sidebar_custom_props
MongoDB	demos/desktop/index	demos/local/index	type document

import current from '/version.js'; import CodeBlock from '@theme/CodeBlock';

MongoDB is a document-oriented database engine.

SheetJS is a JavaScript library for reading and writing data from spreadsheets.

This demo uses SheetJS to exchange data between spreadsheets and MongoDB. We'll explore how to use save tables from a MongoDB collection to spreadsheets and how to add data from spreadsheets into a collection.

:::note

This demo was last tested on 2023 October 12 with MongoDB CE 7.0.2, MongoDB connector module 5.7.0 and NodeJS 20.8.0

:::

Integration Details

The SheetJS NodeJS module can be loaded in NodeJS scripts that use the mongodb NodeJS connector library.

It is straightforward to treat collections as worksheets. Each object maps to a row in the table.

Importing Data

Data stored in an array of objects can be added to MongoDB Collections using Collection#insertMany¹. The SheetJS sheet_to_json method² can generate data from worksheets:

/* import data from a worksheet to a collection */
const aoo = XLSX.utils.sheet_to_json(ws);
await collection.insertMany(aoo, {ordered: true});

Typically worksheet objects are extracted from workbook objects³ generated from the SheetJS read or readFile methods⁴.

Exporting Data

Collection#find⁵ can pull an array of objects from a Mongo Collection.

The SheetJS json_to_sheet method⁶ can take the result and generate a worksheet object.

:::info pass

Normally the method adds a _id field to each object. The recommended way to remove the field is to use a projection to suppress the ID.

:::

/* generate an array of objects from a collection */
const aoo = await collection.find({}, {projection:{_id:0}}).toArray();

/* generate a worksheet from a collection */
const ws = utils.json_to_sheet(aoo);

Using book_new and book_append_sheet⁷, a workbook object can be created. This workbook is typically exported to the filesystem with writeFile⁸.

Complete Example

0. Install MongoDB 7.0 Community Edition⁹. The macOS steps required brew:

brew tap mongodb/brew
brew update
brew install mongodb-community

1. Start a MongoDB server on localhost (follow official instructions).

:::note pass

If brew was used to install MongoDB, the following command starts a server:

/usr/local/opt/mongodb-community/bin/mongod --config /usr/local/etc/mongod.conf

If Homebrew is configured to use /opt/homebrew, the command is:

/opt/homebrew/opt/mongodb-community/bin/mongod --config /opt/homebrew/etc/mongod.conf

:::

2. Create base project and install the dependencies:

{\ mkdir sheetjs-mongo cd sheetjs-mongo npm init -y npm i --save https://cdn.sheetjs.com/xlsx-${current}/xlsx-${current}.tgz mongodb@5.7.0}

3. Save the following to SheetJSMongoCRUD.mjs (the key step is highlighted):

import { writeFile, set_fs, utils } from 'xlsx';
import * as fs from 'fs'; set_fs(fs);
import { MongoClient } from 'mongodb';

const url = 'mongodb://localhost:27017/sheetjs';
const db_name = 'sheetjs';

/* Connect to mongodb server */
const client = await MongoClient.connect(url, { useUnifiedTopology: true });

/* Sample data table */
const db = client.db(db_name);
try { await db.collection('pres').drop(); } catch(e) {}
const pres = db.collection('pres');
await pres.insertMany([
  { name: "Barack Obama", idx: 44 },
  { name: "Donald Trump", idx: 45 },
  { name: "Joseph Biden", idx: 46 }
], {ordered: true});

// highlight-start
/* Create worksheet from collection */
const aoo = await pres.find({}, {projection:{_id:0}}).toArray();
const ws = utils.json_to_sheet(aoo);
// highlight-end

/* Export to XLSX */
const wb = utils.book_new();
utils.book_append_sheet(wb, ws, "Presidents");
writeFile(wb, "SheetJSMongoCRUD.xlsx");

/* Close connection */
client.close();

This script:

• connects to the local MongoDB server using database sheetjs
• removes the pres collection if it already exists
• creates a new collection pres with sample data
• creates a SheetJS worksheet from the collection (highlighted in the snippet)
• creates a SheetJS workbook, adds the worksheet, and exports to XLSX

4. Run the script:

node SheetJSMongoCRUD.mjs

There should be no errors in the terminal. The script will generate the file SheetJSMongoCRUD.xlsx. That file can be opened in a spreadsheet editor.

---

1. See insertMany in the MongoDB documentation. ↩︎

2. See sheet_to_json in "Utilities" ↩︎

3. See "Workbook Object" ↩︎

4. See read and readFile in "Reading Files" ↩︎

5. See find in the MongoDB documentation. ↩︎

6. See json_to_sheet in "Utilities" ↩︎

7. See "Workbook Helpers" in "Utilities" for details on book_new and book_append_sheet. ↩︎

8. See writeFile in "Writing Files" ↩︎

9. See "Install MongoDB Community Edition" in the MongoDB documentation. ↩︎