pool.rs

/*
cargo run -p clickhouse-demo-postgres-client --bin clickhouse-demo-postgres-client-pool postgres://default:xxx@127.0.0.1:9005
*/

use std::env;

use clickhouse_postgres_client::{
    execute, fetch_all, ClickhousePgConnectOptions, ClickhousePgPoolOptions,
};

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    run().await
}

async fn run() -> Result<(), Box<dyn std::error::Error>> {
    let database_url = env::args().nth(1).unwrap_or_else(|| {
        env::var("DATABASE_URL")
            .unwrap_or_else(|_| "postgres://default:xxx@127.0.0.1:9005".to_owned())
    });

    let pool = ClickhousePgPoolOptions::new()
        .max_connections(1)
        .connect_lazy_with(
            database_url
                .parse::<ClickhousePgConnectOptions>()?
                .into_inner(),
        );

    let mut pool_conn = pool.acquire().await?;

    execute("use default", &mut pool_conn).await?;

    let rows = fetch_all("show databases", &mut pool_conn).await?;
    for row in rows.iter() {
        println!("data: {:?}", row.try_get_data());
    }

    Ok(())
}