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.
Clone the application from GitHub
Clone the sample application to your computer:
git clone https://github.com/YugabyteDB-Samples/yugabyte-simple-rust-app.git && cd yugabyte-simple-rust-app
Provide connection parameters
If your cluster is running on YugabyteDB Managed, you need to modify the connection parameters so that the application can establish a connection to the YugabyteDB cluster. (You can skip this step if your cluster is running locally and listening on 127.0.0.1:5433.)
To do this:
-
Open the
sample-app.rs
file in thesrc
directory. -
Set the following configuration-related constants:
- HOST - the host name of your YugabyteDB cluster. For local clusters, use the default (127.0.0.1). For YugabyteDB Managed, select your cluster on the Clusters page, and click Settings. The host is displayed under Connection Parameters.
- PORT - the port number for the driver to use (the default YugabyteDB YSQL port is 5433).
- DB_NAME - the name of the database you are connecting to (the default is
yugabyte
). - USER and PASSWORD - the username and password for the YugabyteDB database. For local clusters, use the defaults (
yugabyte
andyugabyte
). For YugabyteDB Managed, use the credentials 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.
-
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(())
};