Build a Simple CRUD Node.js App with CockroachDB and Knex.js

Warning:
Cockroach Labs will stop providing Assistance Support for v21.1 on November 18, 2022. Prior to that date, upgrade to a more recent version to continue receiving support. For more details, see the Release Support Policy.

This tutorial shows you how build a simple Node.js application with CockroachDB and Knex.js.

Step 1. Start CockroachDB

Create a free cluster

  1. If you haven't already, sign up for a CockroachDB Cloud account.
  2. Log in to your CockroachDB Cloud account.
  3. On the Clusters page, click Create Cluster.
  4. On the Create your cluster page, select Serverless.

    Unless you change your monthly budget, this cluster will be free forever.

  5. Click Create cluster.

    Your cluster will be created in a few seconds and the Create SQL user dialog will display.

Set up your cluster connection

  1. Navigate to the cluster's Overview page, and select Connect.

  2. Under the Connection String tab, download the cluster certificate.

  3. Take note of the connection string provided. You'll use it to connect to the database later in this tutorial.

  1. If you haven't already, download the CockroachDB binary.
  2. Run the cockroach start-single-node command:

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    $ cockroach start-single-node --advertise-addr 'localhost' --insecure
    

    This starts an insecure, single-node cluster.

  3. Take note of the following connection information in the SQL shell welcome text:

    CockroachDB node starting at 2021-08-30 17:25:30.06524 +0000 UTC (took 4.3s)
    build:               CCL v21.1.6 @ 2021/07/20 15:33:43 (go1.15.11)
    webui:               http://localhost:8080
    sql:                 postgresql://root@localhost:26257?sslmode=disable
    

    You'll use the sql connection string to connect to the cluster later in this tutorial.

Warning:

The --insecure flag used in this tutorial is intended for non-production testing only. To run CockroachDB in production, use a secure cluster instead.

Step 2. Get the code

Clone the code's GitHub repo:

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$ git clone https://github.com/cockroachlabs/example-app-node-knex

Step 3. Run the code

To start the app:

  1. Set the DATABASE_URL environment variable to the connection string:

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    $ export DATABASE_URL="postgresql://root@localhost:26257?sslmode=disable"
    
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    $ export DATABASE_URL="<connection-string>"
    

    Where <connection-string> is the connection string you obtained from the CockroachDB Cloud Console.

    The app uses the connection string saved to the DATABASE_URL environment variable to connect to your cluster and execute the code.

  2. Install the app requirements:

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    $ npm install
    
  3. Run the app:

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    $ npm run run
    

    The output should look like this:

    Initializing accounts table...
    New account balances:
    { id: 'bc0f7136-7103-4dc4-88fc-102d5bbd312f', balance: '1000' }
    { id: '35bde7d0-29c9-4277-a117-3eb80c85ae16', balance: '250' }
    { id: '18cc1b2d-be61-4a8d-942c-480f5a6bc207', balance: '0' }
    Transferring funds...
    New account balances:
    { id: 'bc0f7136-7103-4dc4-88fc-102d5bbd312f', balance: '900' }
    { id: '35bde7d0-29c9-4277-a117-3eb80c85ae16', balance: '350' }
    { id: '18cc1b2d-be61-4a8d-942c-480f5a6bc207', balance: '0' }
    Deleting a row...
    New account balances:
    { id: 'bc0f7136-7103-4dc4-88fc-102d5bbd312f', balance: '900' }
    { id: '18cc1b2d-be61-4a8d-942c-480f5a6bc207', balance: '0' }
    

What's next?

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