Query CouchDB Data as a SQL Server Database in Node.js

You can use CData Connect AI to query CouchDB data through a SQL Server interface. Follow the procedure below to create a virtual database for CouchDB in Connect AI and start querying using Node.js.

CData Connect AI provides a pure MySQL, cloud-to-cloud interface for CouchDB, allowing you to easily query live CouchDB data in Node.js — without replicating the data to a natively supported database. As you query data in Node.js, CData Connect AI pushes all supported SQL operations (filters, JOINs, etc) directly to CouchDB, leveraging server-side processing to quickly return CouchDB data.

Configure CouchDB Connectivity for NodeJS

Connectivity to CouchDB from NodeJS is made possible through CData Connect AI. To work with CouchDB data from NodeJS, we start by creating and configuring a CouchDB connection.

1. Log into Connect AI, click Sources, and then click Add Connection

2. Select "CouchDB" from the Add Connection panel

3. Enter the necessary authentication properties to connect to CouchDB.

   Set the following to connect:

   • Url: The Url of your instance. For example: http://localhost:5984
   • User The Apache CouchDB user account used to authenticate.
   • Password The Apache CouchDB password associated with the authenticating user.
   
4. Click Save & Test
5. Navigate to the Permissions tab in the Add CouchDB Connection page and update the User-based permissions.

Add a Personal Access Token

When connecting to Connect AI through the REST API, the OData API, or the Virtual SQL Server, a Personal Access Token (PAT) is used to authenticate the connection to Connect AI. It is best practice to create a separate PAT for each service to maintain granularity of access.

1. Click on the Gear icon () at the top right of the Connect AI app to open the settings page.
2. On the Settings page, go to the Access Tokens section and click Create PAT.
3. Give the PAT a name and click Create.
4. The personal access token is only visible at creation, so be sure to copy it and store it securely for future use.

With the connection configured and a PAT generated, you are ready to connect to CouchDB data from Node.js.

Query CouchDB from Node.js

The following example shows how to define a connection and execute queries to CouchDB with the SQL Server module. You will need the following information:

• server: tds.cdata.com
• port: 14333
• user: a Connect AI user (e.g. [email protected])
• password: the PAT for the above user
• database: The connection you configured for CouchDB (ApacheCouchDB1)

Connect to CouchDB data and start executing queries with the code below:

var sql = require('mssql')
var config = {
	server: 'tds.cdata.com',
	port: 14333, 
	user: '[email protected]', //update me
	password: 'CONNECT_USER_PAT', //update me	
	options: {
		encrypt: true,
		database: 'ApacheCouchDB1'
	}
}

sql.connect(config, err => { 
    if(err){
        throw err ;
    }
    new sql.Request().query('SELECT * FROM Movies', (err, result) => {
        console.dir(result)
    })
        
});

sql.on('error', err => {
    console.log("SQL Error: " ,err);
})