77 lines
2.7 KiB
Rust
77 lines
2.7 KiB
Rust
//! A throwaway `nats-server` with `JetStream`, for the tests whose subject is
|
|
//! the server's own behaviour: what a stream keeps and what a request gets.
|
|
//!
|
|
//! The same shape as `swarm-queue-client`'s: the binary comes from
|
|
//! [`NATS_SERVER_ENV`], which `nix/checks.nix` and `nix/devshell.nix` export,
|
|
//! and a test that needs it panics when it is unset rather than skipping.
|
|
|
|
use std::path::Path;
|
|
use std::process::{Child, Command, Stdio};
|
|
use std::time::Duration;
|
|
|
|
/// The variable naming the `nats-server` binary.
|
|
const NATS_SERVER_ENV: &str = "HIVE_NATS_SERVER";
|
|
|
|
/// The subdirectory holding nothing but the server's ports file.
|
|
const PORTS_DIR: &str = "ports";
|
|
|
|
/// A running server on a loopback port it bound itself. Dropping it kills
|
|
/// the server and removes its directory.
|
|
pub struct TestNats {
|
|
child: Child,
|
|
dir: tempfile::TempDir,
|
|
}
|
|
|
|
impl TestNats {
|
|
pub fn start() -> Self {
|
|
let bin = std::env::var(NATS_SERVER_ENV).unwrap_or_else(|_| {
|
|
panic!("{NATS_SERVER_ENV} is exported by nix/checks.nix and nix/devshell.nix")
|
|
});
|
|
let dir = tempfile::Builder::new()
|
|
.prefix("test-nats-")
|
|
.tempdir()
|
|
.expect("a fresh directory for the server");
|
|
std::fs::create_dir(dir.path().join(PORTS_DIR)).expect("the ports file directory");
|
|
let child = Command::new(&bin)
|
|
.args(["-a", "127.0.0.1", "-p", "-1", "-js", "-sd"])
|
|
.arg(dir.path().join("store"))
|
|
.arg("--ports_file_dir")
|
|
.arg(dir.path().join(PORTS_DIR))
|
|
.stdout(Stdio::null())
|
|
.stderr(Stdio::null())
|
|
.spawn()
|
|
.unwrap_or_else(|e| panic!("starting {bin}: {e}"));
|
|
Self { child, dir }
|
|
}
|
|
|
|
/// A client connected to the server, once it accepts connections.
|
|
pub async fn client(&self) -> async_nats::Client {
|
|
for _ in 0..100 {
|
|
if let Some(url) = announced_url(&self.dir.path().join(PORTS_DIR))
|
|
&& let Ok(client) = async_nats::connect(&url).await
|
|
{
|
|
return client;
|
|
}
|
|
tokio::time::sleep(Duration::from_millis(100)).await;
|
|
}
|
|
panic!(
|
|
"nats-server in {} never accepted a connection",
|
|
self.dir.path().display()
|
|
);
|
|
}
|
|
}
|
|
|
|
/// The client URL in the ports file the server writes once it listens.
|
|
fn announced_url(dir: &Path) -> Option<String> {
|
|
let ports = std::fs::read_dir(dir).ok()?.next()?.ok()?;
|
|
let ports: serde_json::Value =
|
|
serde_json::from_slice(&std::fs::read(ports.path()).ok()?).ok()?;
|
|
ports["nats"][0].as_str().map(str::to_owned)
|
|
}
|
|
|
|
impl Drop for TestNats {
|
|
fn drop(&mut self) {
|
|
let _ = self.child.kill();
|
|
let _ = self.child.wait();
|
|
}
|
|
}
|