AsyncPgConnection SSL error when PgConnection works

[roudikk]

When trying to connect to my database using AsyncPgConnection I get a SSL error but it works using PgConnection

Setup

My postgres URL is just a simple username/password postgres:// url with no additional query params.

Cargo.toml

[dependencies]
diesel = { version = "2.0.3", features = ["postgres", "r2d2", "extras", "chrono", "uuid"] }
diesel-async = { version = "0.2.1", features = ["postgres", "bb8"] }
dotenv = "0.15.0"
serde = { version = "1.0.159", features = ["derive"]}
serde_json = "1.0.95"
chrono = { version = "0.4.24", features = ["serde"] }
bb8 = "0.8"
axum = "0.6.12"
axum-macros = "0.3.7"
tokio = { version = "1.27.0", features = ["full"] }
tracing = "0.1.37"
tracing-subscriber = { version = "0.3.16", features = ["env-filter"] }

Steps to reproduce

Using PgConnection:

#[tokio::main]
async fn main() {
    dotenv().ok();

    let database_url = env::var("DATABASE_URL").expect("DATABASE_URL must be set");

    let mut connection = PgConnection::establish(&database_url).unwrap();
    println!("Established!");
    let orgs = orgs::table.load::<Org>(&mut connection).unwrap();
    println!("{:?}", orgs);
}

Output:

Established!
[]

Using AsyncPgConnection:

#[tokio::main]
async fn main() {
    dotenv().ok();

    let database_url = env::var("DATABASE_URL").expect("DATABASE_URL must be set");

    let mut connection = AsyncPgConnection::establish(&database_url).await.unwrap();
    println!("Established!");
    let orgs = orgs::table.load::<Org>(&mut connection).await.unwrap();
    println!("{:?}", orgs);

Output

thread 'main' panicked at 'called `Result::unwrap()` on an `Err` value: CouldntSetupConfiguration(DatabaseError(Unknown, "SSL/TLS required"))', src\main.rs:27:76

Checklist

• I have already looked over the issue tracker for similar possible closed issues.

• This issue can be reproduced on Rust's stable channel. (Your issue will be
  closed if this is not the case)
• This issue can be reproduced without requiring a third party crate

[weiznich]

This is expected behavior as tokio-postgres does not provide support for TLS/SSL connections by default. You need to setup that by including additional dependencies. As there are multiple options there I choose to not include that directly in diesel. You can construct a AsyncPgConnection for a tokio-postgres Client that supports TLS/SSL connections via AsyncPgConnection::try_from.

Also see this example: https://github.com/weiznich/diesel_async/tree/main/examples/postgres/pooled-with-rustls

Closed as this is not an bug