In-memory SQLite

The model-sqlite feature ships an ergonomic constructor that opens a SQLite ":memory:" database without a file path, hostname, or credentials. All operations are async fn.

DbPool::memory() — isolated in-memory database

DbPool::memory().await creates a sqlx::Pool with max_connections = 1 connected to sqlite::memory:. Each call returns a separate, independent in-memory database — ideal for tests that must not share state.

use rust_web_server::model::{DbPool, Value};

let pool = DbPool::memory().await.unwrap();

pool.execute(
    "CREATE TABLE items (id INTEGER PRIMARY KEY, name TEXT)",
    &[],
).await.unwrap();

pool.execute(
    "INSERT INTO items (name) VALUES (?)",
    &[Value::Text("apple".into())],
).await.unwrap();

let rows = pool.query_rows("SELECT name FROM items", &[]).await.unwrap();
assert_eq!(1, rows.len());
let name: String = rows[0].get("name").unwrap();
assert_eq!("apple", name);

Test isolation

Each DbPool::memory().await call is a new, empty database. Two pools have no shared state:

async fn test_db() -> DbPool {
    let pool = DbPool::memory().await.unwrap();
    pool.execute("CREATE TABLE users (id INTEGER PRIMARY KEY, name TEXT)", &[]).await.unwrap();
    pool
}

// Test A
let pool_a = test_db().await;
pool_a.execute("INSERT INTO users (name) VALUES (?)", &[Value::Text("Alice".into())]).await.unwrap();

// Test B — completely isolated
let pool_b = test_db().await;
let rows = pool_b.query_rows("SELECT * FROM users", &[]).await.unwrap();
assert!(rows.is_empty());  // Alice is only in pool_a's database

Use #[tokio::test] for async tests:

#[tokio::test]
async fn test_example() {
    let pool = DbPool::memory().await.unwrap();
    pool.execute("CREATE TABLE t (v TEXT)", &[]).await.unwrap();
    let rows = pool.query_rows("SELECT * FROM t", &[]).await.unwrap();
    assert!(rows.is_empty());
}

Feature requirement

DbPool::memory() requires the model-sqlite feature, which also implies http2 (tokio runtime):

[dependencies]
rust-web-server = { version = "17", features = ["model-sqlite"] }