Build a Node.js App with CockroachDB

2020-02-16

This tutorial shows you how build a simple Node.js application with CockroachDB using a PostgreSQL-compatible driver or ORM.

We have tested the Node.js pg driver and the Sequelize ORM enough to claim beta-level support, so those are featured here. If you encounter problems, please open an issue with details to help us make progress toward full support.

Before you begin

  1. Install CockroachDB.
  2. Start up a secure or insecure local cluster.
  3. Choose the instructions that correspond to whether your cluster is secure or insecure:

Step 1. Install Node.js packages

To let your application communicate with CockroachDB, install the Node.js pg driver:

$ npm install pg

The example app on this page also requires async:

$ npm install async
## Step 2. Create the `maxroach` user and `bank` database {% include {{page.version.version}}/app/create-maxroach-user-and-bank-database.md %} ## Step 3. Generate a certificate for the `maxroach` user Create a certificate and key for the `maxroach` user by running the following command. The code samples will run as this user. {% include copy-clipboard.html %} ~~~ shell $ cockroach cert create-client maxroach --certs-dir=certs --ca-key=my-safe-directory/ca.key ~~~ ## Step 4. Run the Node.js code Now that you have a database and a user, you'll run code to create a table and insert some rows, and then you'll run code to read and update values as an atomic [transaction](transactions.html). ### Basic statements First, use the following code to connect as the `maxroach` user and execute some basic SQL statements, creating a table, inserting rows, and reading and printing the rows. Download the [`basic-sample.js`](https://raw.githubusercontent.com/cockroachdb/docs/master/_includes/v2.1/app/basic-sample.js) file, or create the file yourself and copy the code into it. {% include copy-clipboard.html %} ~~~ js {% include {{page.version.version}}/app/basic-sample.js %} ~~~ Then run the code: {% include copy-clipboard.html %} ~~~ shell $ node basic-sample.js ~~~ The output should be: ~~~ Initial balances: { id: '1', balance: '1000' } { id: '2', balance: '250' } ~~~ ### Transaction (with retry logic) Next, use the following code to again connect as the `maxroach` user but this time execute a batch of statements as an atomic transaction to transfer funds from one account to another and then read the updated values, where all included statements are either committed or aborted. Download the [`txn-sample.js`](https://raw.githubusercontent.com/cockroachdb/docs/master/_includes/v2.1/app/txn-sample.js) file, or create the file yourself and copy the code into it. {% include v2.1/client-transaction-retry.md %} {% include copy-clipboard.html %} ~~~ js {% include {{page.version.version}}/app/txn-sample.js %} ~~~ Then run the code: {% include copy-clipboard.html %} ~~~ shell $ node txn-sample.js ~~~ The output should be: ~~~ Balances after transfer: { id: '1', balance: '900' } { id: '2', balance: '350' } ~~~ To verify that funds were transferred from one account to another, start the [built-in SQL client](use-the-built-in-sql-client.html): {% include copy-clipboard.html %} ~~~ shell $ cockroach sql --certs-dir=certs --database=bank ~~~ To check the account balances, issue the following statement: {% include copy-clipboard.html %} ~~~ sql > SELECT id, balance FROM accounts; ~~~ ~~~ +----+---------+ | id | balance | +----+---------+ | 1 | 900 | | 2 | 350 | +----+---------+ (2 rows) ~~~
## Step 2. Create the `maxroach` user and `bank` database {% include {{page.version.version}}/app/insecure/create-maxroach-user-and-bank-database.md %} ## Step 3. Run the Node.js code Now that you have a database and a user, you'll run code to create a table and insert some rows, and then you'll run code to read and update values as an atomic [transaction](transactions.html). ### Basic statements First, use the following code to connect as the `maxroach` user and execute some basic SQL statements, creating a table, inserting rows, and reading and printing the rows. Download the [`basic-sample.js`](https://raw.githubusercontent.com/cockroachdb/docs/master/_includes/v2.1/app/insecure/basic-sample.js) file, or create the file yourself and copy the code into it. {% include copy-clipboard.html %} ~~~ js {% include {{page.version.version}}/app/insecure/basic-sample.js %} ~~~ Then run the code: {% include copy-clipboard.html %} ~~~ shell $ node basic-sample.js ~~~ The output should be: ~~~ Initial balances: { id: '1', balance: '1000' } { id: '2', balance: '250' } ~~~ ### Transaction (with retry logic) Next, use the following code to again connect as the `maxroach` user but this time execute a batch of statements as an atomic transaction to transfer funds from one account to another and then read the updated values, where all included statements are either committed or aborted. Download the [`txn-sample.js`](https://raw.githubusercontent.com/cockroachdb/docs/master/_includes/v2.1/app/insecure/txn-sample.js) file, or create the file yourself and copy the code into it. {% include v2.1/client-transaction-retry.md %} {% include copy-clipboard.html %} ~~~ js {% include {{page.version.version}}/app/insecure/txn-sample.js %} ~~~ Then run the code: {% include copy-clipboard.html %} ~~~ shell $ node txn-sample.js ~~~ The output should be: ~~~ Balances after transfer: { id: '1', balance: '900' } { id: '2', balance: '350' } ~~~ To verify that funds were transferred from one account to another, start the [built-in SQL client](use-the-built-in-sql-client.html): {% include copy-clipboard.html %} ~~~ shell $ cockroach sql --insecure --database=bank ~~~ To check the account balances, issue the following statement: {% include copy-clipboard.html %} ~~~ sql > SELECT id, balance FROM accounts; ~~~ ~~~ +----+---------+ | id | balance | +----+---------+ | 1 | 900 | | 2 | 350 | +----+---------+ (2 rows) ~~~

What's next?

Read more about using the Node.js pg driver.

You might also be interested in using a local cluster to explore the following CockroachDB benefits: