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| 1 | +// Example to listen on port 8080 locally, forwarding to port 80 in the example pod. |
| 2 | +// Similar to `kubectl port-forward pod/example 8080:80`. |
| 3 | +use std::{convert::Infallible, net::SocketAddr, sync::Arc}; |
| 4 | + |
| 5 | +use futures::FutureExt; |
| 6 | +use hyper::{ |
| 7 | + service::{make_service_fn, service_fn}, |
| 8 | + Body, Request, Response, Server, |
| 9 | +}; |
| 10 | +use tokio::sync::Mutex; |
| 11 | +use tower::ServiceExt; |
| 12 | + |
| 13 | +use k8s_openapi::api::core::v1::Pod; |
| 14 | +use kube::{ |
| 15 | + api::{Api, DeleteParams, PostParams}, |
| 16 | + runtime::wait::{await_condition, conditions::is_pod_running}, |
| 17 | + Client, ResourceExt, |
| 18 | +}; |
| 19 | + |
| 20 | +#[tokio::main] |
| 21 | +async fn main() -> anyhow::Result<()> { |
| 22 | + std::env::set_var("RUST_LOG", "info,kube=debug"); |
| 23 | + env_logger::init(); |
| 24 | + let client = Client::try_default().await?; |
| 25 | + let namespace = std::env::var("NAMESPACE").unwrap_or_else(|_| "default".into()); |
| 26 | + |
| 27 | + let p: Pod = serde_json::from_value(serde_json::json!({ |
| 28 | + "apiVersion": "v1", |
| 29 | + "kind": "Pod", |
| 30 | + "metadata": { "name": "example" }, |
| 31 | + "spec": { |
| 32 | + "containers": [{ |
| 33 | + "name": "nginx", |
| 34 | + "image": "nginx", |
| 35 | + }], |
| 36 | + } |
| 37 | + }))?; |
| 38 | + |
| 39 | + let pods: Api<Pod> = Api::namespaced(client, &namespace); |
| 40 | + // Stop on error including a pod already exists or is still being deleted. |
| 41 | + pods.create(&PostParams::default(), &p).await?; |
| 42 | + |
| 43 | + // Wait until the pod is running, otherwise we get 500 error. |
| 44 | + let running = await_condition(pods.clone(), "example", is_pod_running()); |
| 45 | + let _ = tokio::time::timeout(std::time::Duration::from_secs(30), running).await?; |
| 46 | + |
| 47 | + // Get `Portforwarder` that handles the WebSocket connection. |
| 48 | + // There's no need to spawn a task to drive this, but it can be awaited to be notified on error. |
| 49 | + let mut forwarder = pods.portforward("example", &[80]).await?; |
| 50 | + let port = forwarder.ports()[0].stream().unwrap(); |
| 51 | + |
| 52 | + // let hyper drive the HTTP state in our DuplexStream via a task |
| 53 | + let (sender, connection) = hyper::client::conn::handshake(port).await?; |
| 54 | + tokio::spawn(async move { |
| 55 | + if let Err(e) = connection.await { |
| 56 | + log::error!("error in connection: {}", e); |
| 57 | + } |
| 58 | + }); |
| 59 | + // The following task is only used to show any error from the forwarder. |
| 60 | + // This example can be stopped with Ctrl-C if anything happens. |
| 61 | + tokio::spawn(async move { |
| 62 | + if let Err(e) = forwarder.await { |
| 63 | + log::error!("forwarder errored: {}", e); |
| 64 | + } |
| 65 | + }); |
| 66 | + |
| 67 | + // Shared `SendRequest<Body>` to relay the request. |
| 68 | + let context = Arc::new(Mutex::new(sender)); |
| 69 | + let make_service = make_service_fn(move |_conn| { |
| 70 | + let context = context.clone(); |
| 71 | + let service = service_fn(move |req| handle(context.clone(), req)); |
| 72 | + async move { Ok::<_, Infallible>(service) } |
| 73 | + }); |
| 74 | + |
| 75 | + let (tx, rx) = tokio::sync::oneshot::channel::<()>(); |
| 76 | + let addr = SocketAddr::from(([127, 0, 0, 1], 8080)); |
| 77 | + let server = Server::bind(&addr) |
| 78 | + .serve(make_service) |
| 79 | + .with_graceful_shutdown(async { |
| 80 | + rx.await.ok(); |
| 81 | + }); |
| 82 | + println!("Forwarding http://{} to port 80 in the pod", addr); |
| 83 | + println!("Try opening http://{0} in a browser, or `curl http://{0}`", addr); |
| 84 | + println!("Use Ctrl-C to stop the server and delete the pod"); |
| 85 | + // Stop the server and delete the pod on Ctrl-C. |
| 86 | + tokio::spawn(async move { |
| 87 | + tokio::signal::ctrl_c().map(|_| ()).await; |
| 88 | + log::info!("stopping the server"); |
| 89 | + let _ = tx.send(()); |
| 90 | + }); |
| 91 | + if let Err(e) = server.await { |
| 92 | + log::error!("server error: {}", e); |
| 93 | + } |
| 94 | + |
| 95 | + log::info!("deleting the pod"); |
| 96 | + pods.delete("example", &DeleteParams::default()) |
| 97 | + .await? |
| 98 | + .map_left(|pdel| { |
| 99 | + assert_eq!(pdel.name(), "example"); |
| 100 | + }); |
| 101 | + |
| 102 | + Ok(()) |
| 103 | +} |
| 104 | + |
| 105 | +// Simply forwards the request to the port through the shared `SendRequest<Body>`. |
| 106 | +async fn handle( |
| 107 | + context: Arc<Mutex<hyper::client::conn::SendRequest<hyper::Body>>>, |
| 108 | + req: Request<Body>, |
| 109 | +) -> Result<Response<Body>, Infallible> { |
| 110 | + let mut sender = context.lock().await; |
| 111 | + let response = sender.ready().await.unwrap().send_request(req).await.unwrap(); |
| 112 | + Ok(response) |
| 113 | +} |
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