Build a Rust application

The following tutorial shows a small Rust application that connects to a YugabyteDB cluster using the Rust-Postgres driver and performs basic SQL operations. Use the application as a template to get started with YugabyteDB Managed in Rust.

Prerequisites

• Rust development environment. The sample application was created for Rust 1.58 but should work for earlier and later versions.

YugabyteDB Managed

• You have a cluster deployed in YugabyteDB Managed. To get started, use the Quick start.
• You downloaded the cluster CA certificate and added your computer to the cluster IP allow list. Refer to Before you begin.

Clone the application from GitHub

Clone the sample application to your computer:

git clone https://github.com/yugabyte/yugabyte-simple-rust-app && cd yugabyte-simple-rust-app

Provide connection parameters

The application needs to establish a connection to the YugabyteDB cluster. To do this:

1. Open the sample-app.rs file in the src directory.

2. Set the following configuration-related constants:

   • HOST - the host name of your YugabyteDB cluster. To obtain a YugabyteDB Managed cluster host name, sign in to YugabyteDB Managed, select your cluster on the Clusters page, and click Settings. The host is displayed under Network Access.
   • PORT - the port number that will be used by the driver (the default YugabyteDB YSQL port is 5433).
   • DB_NAME - the name of the database you are connecting to (the default database is named yugabyte).
   • USER and PASSWORD - the username and password for the YugabyteDB database. If you are using the credentials you created when deploying a cluster in YugabyteDB Managed, these can be found in the credentials file you downloaded.
   • SSL_MODE - the SSL mode to use. YugabyteDB Managed requires SSL connections; use SslMode::Require.
   • SSL_ROOT_CERT - the full path to the YugabyteDB Managed cluster CA certificate.

3. Save the file.

Build and run the application

Build and run the application.

$ cargo run

The driver is included in the dependencies list of the Cargo.toml file and installed automatically the first time you run the application.

You should see output similar to the following:

>>>> Successfully connected to YugabyteDB!
>>>> Successfully created table DemoAccount.
>>>> Selecting accounts:
name = Jessica, age = 28, country = USA, balance = 10000
name = John, age = 28, country = Canada, balance = 9000
>>>> Transferred 800 between accounts.
>>>> Selecting accounts:
name = Jessica, age = 28, country = USA, balance = 9200
name = John, age = 28, country = Canada, balance = 9800

You have successfully executed a basic Rust application that works with YugabyteDB Managed.

Explore the application logic

Open the sample-app.rs file in the yugabyte-simple-rust-app/src folder to review the methods.

connect

The connect method establishes a connection with your cluster via the Rust-Postgres driver.

let mut cfg = Config::new();

cfg.host(HOST).port(PORT).dbname(DB_NAME).
    user(USER).password(PASSWORD).ssl_mode(SSL_MODE);

let mut builder = SslConnector::builder(SslMethod::tls())?;
builder.set_ca_file(SSL_ROOT_CERT)?;
let connector = MakeTlsConnector::new(builder.build());

let client = cfg.connect(connector)?;

create_database

The create_database method uses PostgreSQL-compliant DDL commands to create a sample database.

client.execute("DROP TABLE IF EXISTS DemoAccount", &[])?;

client.execute("CREATE TABLE DemoAccount (
                id int PRIMARY KEY,
                name varchar,
                age int,
                country varchar,
                balance int)", &[])?;

client.execute("INSERT INTO DemoAccount VALUES
                (1, 'Jessica', 28, 'USA', 10000),
                (2, 'John', 28, 'Canada', 9000)", &[])?;

select_accounts

The select_accounts method queries your distributed data using the SQL SELECT statement.

for row in client.query("SELECT name, age, country, balance FROM DemoAccount", &[])? {
    let name: &str = row.get("name");
    let age: i32 = row.get("age");
    let country: &str = row.get("country");
    let balance: i32 = row.get("balance");

    println!("name = {}, age = {}, country = {}, balance = {}",
        name, age, country, balance);
}

transfer_money_between_accounts

The transfer_money_between_accounts method updates your data consistently with distributed transactions.

let mut txn = client.transaction()?;

let exec_txn = || -> Result<(), DBError> {
    txn.execute("UPDATE DemoAccount SET balance = balance - $1 WHERE name = \'Jessica\'", &[&amount])?;
    txn.execute("UPDATE DemoAccount SET balance = balance + $1 WHERE name = \'John\'", &[&amount])?;
    txn.commit()?;

    Ok(())
};

Learn more

Rust-Postgres driver

Explore more applications

Deploy clusters in YugabyteDB Managed

Connect to applications in YugabyteDB Managed