klickhouse 0.15.0

Klickhouse is a pure Rust SDK for working with Clickhouse with the native protocol in async environments with minimal boilerplate and maximal performance.
Documentation 
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use std::net::SocketAddr;
use tokio::net::ToSocketAddrs;

use crate::{Client, ClientOptions, KlickhouseError, convert::UnitValue};

#[derive(Clone)]
pub struct ConnectionManager {
    destination: Vec<SocketAddr>,
    options: ClientOptions,
    prequel: Option<String>,
}

impl ConnectionManager {
    pub async fn new<A: ToSocketAddrs>(
        destination: A,
        options: ClientOptions,
    ) -> std::io::Result<Self> {
        Ok(Self {
            destination: tokio::net::lookup_host(destination).await?.collect(),
            options,
            prequel: None,
        })
    }

    pub fn with_prequel(mut self, prequel: impl Into<String>) -> Self {
        self.prequel = Some(prequel.into());
        self
    }
}

impl bb8::ManageConnection for ConnectionManager {
    type Connection = Client;
    type Error = KlickhouseError;

    async fn connect(&self) -> Result<Self::Connection, Self::Error> {
        let client = Client::connect(&self.destination[..], self.options.clone()).await?;
        if let Some(prequel) = &self.prequel {
            client.execute(prequel).await?;
        }
        Ok(client)
    }

    async fn is_valid(&self, conn: &mut Self::Connection) -> Result<(), Self::Error> {
        let _ = conn.query_one::<UnitValue<String>>("select '';").await?;
        Ok(())
    }

    fn has_broken(&self, conn: &mut Self::Connection) -> bool {
        conn.is_closed()
    }
}