ephemeral-postgres

Ephemeral PostgreSQL instances for Rust integration tests, backed by testcontainers (Docker).

Each test starts its own PostgreSQL container and carves out isolated databases from it, so tests never share state. Containers are removed automatically when the cluster is dropped.

Requirements

A running Docker daemon. Docker is needed only at test runtime to start containers — it is not required to build the crate or its documentation.

Install

[dev-dependencies]
ephemeral-postgres = "0.1"

Usage

use ephemeral_postgres::cluster::Cluster;
use sqlx::Row;

#[tokio::test]
async fn each_test_gets_an_isolated_database() {
    let cluster = Cluster::start().await.unwrap();
    let database = cluster.create_database().await.unwrap();

    let value: i32 = sqlx::query("SELECT 1::int AS value")
        .fetch_one(database.pool())
        .await
        .unwrap()
        .get("value");

    assert_eq!(value, 1);
}

Cluster::start() starts one PostgreSQL container.
create_database() / create_database_with_id(uuid) create freshly-isolated databases that share the container.
database.pool() returns an sqlx::PgPool connected to that database.
Dropping the last Arc<Cluster> stops and removes the container.

Configuration

use std::time::Duration;

use ephemeral_postgres::cluster::Cluster;
use ephemeral_postgres::cluster_params::ClusterParams;

let cluster = Cluster::start_with_params(ClusterParams {
    image_tag: "17".to_owned(),
    readiness_timeout: Duration::from_secs(60),
})
.await?;

ClusterParams::default() pins a specific postgres image digest and waits up to 30 seconds for the server to accept connections.

License