Continuing this short series of writing a simple echo service web API along with the docker and k8s requirements, we’re now going to turn our attention to a Rust implementation.<\/p>\n
Implementation<\/strong><\/p>\n I’m using JetBrains RustRover for this project, so I created a project named echo_service<\/em>.<\/p>\n Next, add the following to the dependencies of Cargo.toml<\/p>\n and now the main.rs can be replaced with <\/p>\n Dockerfile<\/strong><\/p>\n Next up we need to create our Dockerfile<\/p>\n Note: In Linux port 80 might be locked down, hence we use port 8080 by default.<\/em><\/p>\n To build this, run <\/p>\n Don’t forget to change the name to your preferred name.<\/em><\/p>\n and to test this, run<\/p>\n Kubernetes<\/strong><\/p>\n If all wen well we’ve not tested our application and see it working from a docker image, so now we need to create the deployment etc. for Kubernete’s. Let’s assume you’ve pushed you image to Docker or another container registry such as Azure – I’m call my container registry putridparrotreg<\/em>.<\/p>\n I’m also not going to use helm at this point as I just want a (relatively) simple yaml file to run from kubectl, so create a deployment.yaml file, we’ll store all the configurations, deployment, service and ingress in this one file jus for simplicity.<\/p>\n\r\naxum = "0.7"\r\ntokio = { version = "1", features = ["full"] }\r\nserde = { version = "1", features = ["derive"] }\r\n<\/pre>\n\r\nuse axum::{\r\n routing::get,\r\n extract::Query,\r\n http::StatusCode,\r\n response::IntoResponse,\r\n Router,\r\n};\r\nuse tokio::net::TcpListener;\r\nuse axum::serve;\r\nuse std::net::SocketAddr;\r\nuse serde::Deserialize;\r\n\r\n#[derive(Deserialize)]\r\nstruct EchoParams {\r\n text: Option<String>,\r\n}\r\n\r\nasync fn echo(Query(params): Query<EchoParams>) -> String {\r\n format!("Rust Echo: {}", params.text.unwrap_or_default())\r\n}\r\n\r\nasync fn livez() -> impl IntoResponse {\r\n (StatusCode::OK, "OK")\r\n}\r\n\r\nasync fn readyz() -> impl IntoResponse {\r\n (StatusCode::OK, "Ready")\r\n}\r\n\r\n#[tokio::main]\r\nasync fn main() {\r\n let app = Router::new()\r\n .route("\/echo", get(echo))\r\n .route("\/livez", get(livez))\r\n .route("\/readyz", get(readyz));\r\n\r\n let addr = SocketAddr::from(([0, 0, 0, 0], 8080));\r\n println!("Running on http:\/\/{}", addr);\r\n\r\n let listener = TcpListener::bind(addr).await.unwrap();\r\n serve(listener, app).await.unwrap();\r\n\r\n}\r\n<\/pre>\n\r\nFROM rust:1.72-slim AS builder\r\n\r\nWORKDIR \/app\r\nCOPY . .\r\n\r\nRUN cargo build --release\r\n\r\nFROM debian:bookworm-slim\r\n\r\nRUN apt-get update && apt-get install -y ca-certificates && \\\r\n rm -rf \/var\/lib\/apt\/lists\/*\r\n\r\nCOPY --from=builder \/app\/target\/release \/usr\/local\/bin\/echo_service\r\n\r\nRUN chmod +x \/usr\/local\/bin\/echo_service\r\n\r\nEXPOSE 8080\r\n\r\nENTRYPOINT ["\/usr\/local\/bin\/echo_service\/echo_service"]\r\n<\/pre>\n
\r\ndocker build -t putridparrot.echo_service:v1 .\r\n<\/pre>\n
\r\ndocker run -p 8080:8080 putridparrot.echo_service:v1\r\n<\/pre>\n
\r\napiVersion: apps\/v1\r\nkind: Deployment\r\nmetadata:\r\n name: echo\r\n namespace: dev\r\n labels:\r\n app: echo\r\nspec:\r\n replicas: 1\r\n selector:\r\n matchLabels:\r\n app: echo\r\n template:\r\n metadata:\r\n labels:\r\n app: echo\r\n spec:\r\n containers:\r\n - name: echo\r\n image: putridparrotreg\/putridparrot.echo_service:v1\r\n ports:\r\n - containerPort: 8080\r\n resources:\r\n requests:\r\n memory: "100Mi"\r\n cpu: "100m"\r\n limits:\r\n memory: "200Mi"\r\n cpu: "200m"\r\n livenessProbe:\r\n httpGet:\r\n path: \/livez\r\n port: 8080\r\n initialDelaySeconds: 30\r\n periodSeconds: 10\r\n readinessProbe:\r\n httpGet:\r\n path: \/readyz\r\n port: 8080\r\n initialDelaySeconds: 5\r\n periodSeconds: 5\r\n\r\n---\r\napiVersion: v1\r\nkind: Service\r\nmetadata:\r\n name: echo_service\r\n namespace: dev\r\n labels:\r\n app: echo\r\nspec:\r\n type: ClusterIP\r\n selector:\r\n app: echo \r\n ports:\r\n - name: http\r\n port: 80\r\n targetPort: 8080\r\n protocol: TCP\r\n---\r\napiVersion: networking.k8s.io\/v1\r\nkind: Ingress\r\nmetadata:\r\n name: echo-ingress\r\n namespace: dev\r\n annotations:\r\n kubernetes.io\/ingress.class: "nginx"\r\n nginx.ingress.kubernetes.io\/rewrite-target: \/\r\nspec:\r\n rules:\r\n - host: mydomain.com\r\n http:\r\n paths:\r\n - path: \/\r\n pathType: Prefix\r\n backend:\r\n service:\r\n name: echo_service\r\n port:\r\n number: 80\r\n<\/pre>\n