aws-smithy-http-client

HTTP client abstractions for generated smithy clients.

Connection test harness

The wire-mock feature exposes a deterministic connection-level test harness at test_util::wire::connection. Each accepted socket receives one complete script:

use aws_smithy_http_client::test_util::wire::connection::{
    ConnectionTestHarness, EndpointPlan, Http1Response, Http1Script,
};
use std::net::{IpAddr, Ipv4Addr};

# async fn example() -> Result<(), Box<dyn std::error::Error>> {
let harness = ConnectionTestHarness::builder()
    .endpoint(
        IpAddr::V4(Ipv4Addr::LOCALHOST),
        EndpointPlan::unbounded(Http1Script::serve(
            Http1Response::ok().body("ok"),
        )),
    )
    .build()
    .await?;

let endpoint = harness.endpoint_url();
// Configure the client with `endpoint` and `harness.dns_resolver()`.

harness.shutdown().await?;
# Ok(())
# }

Multi-address loopback tests

Some tests simulate multiple resolved IP addresses by binding to different loopback addresses (127.0.0.1, 127.0.0.2, and so on) on the same port. Linux and Windows normally make the full 127.0.0.0/8 block available without additional setup. On macOS, configure the additional loopback aliases before running the tests:

sudo ifconfig lo0 alias 127.0.0.2
sudo ifconfig lo0 alias 127.0.0.3

These aliases do not persist across reboots. A test that requires an unavailable loopback address fails with a message identifying the address and these setup instructions.

This crate is part of the AWS SDK for Rust and the smithy-rs code generator. In most cases, it should not be used directly.