feat: add Rust buildpack and smoke test

Author: casibbald

.gitignore

@@ -1 +1,3 @@
 .bin/
+smoke/testdata/rust/target/
+smoke/testdata/rust/Cargo.lock

README.md

@@ -5,7 +5,7 @@
 This builder uses the [Paketo Jammy Base
 Stack](https://github.com/paketo-buildpacks/jammy-base-stack) (Ubuntu Jammy
 Jellyfish build and run images) with buildpacks for Java,
-Java Native Image, Go, Python, .NET, Node.js, Apache HTTPD, NGINX and Procfile.
+Java Native Image, Go, Python, .NET, Node.js, Apache HTTPD, NGINX, Procfile and Rust.
 
 To see which versions of build and run images, buildpacks, and the lifecycle
 that are contained within a given builder version, see the

builder.toml

@@ -36,6 +36,10 @@ description = "Ubuntu 22.04 Jammy Jellyfish base image with buildpacks for Java,
   uri = "docker://docker.io/paketobuildpacks/web-servers:4.0.3"
   version = "4.0.3"
 
+[[buildpacks]]
+  uri = "docker://ghcr.io/octopilot/rust:0.1.1"
+  version = "0.1.1"
+
 [lifecycle]
   version = "0.21.1"
 
@@ -93,6 +97,12 @@ description = "Ubuntu 22.04 Jammy Jellyfish base image with buildpacks for Java,
     id = "paketo-buildpacks/procfile"
     version = "5.12.1"
 
+[[order]]
+
+  [[order.group]]
+    id = "octopilot/rust"
+    version = "0.1.1"
+
 [stack]
   build-image = "docker.io/paketobuildpacks/build-jammy-base:0.1.196"
   id = "io.buildpacks.stacks.jammy"

smoke/init_test.go

@@ -37,6 +37,7 @@ func TestSmoke(t *testing.T) {
 	suite("Procfile", testProcfile)
 	suite("Python", testPython)
 	suite("Ruby", testRuby)
+	suite("Rust", testRust)
 	suite("Web Servers", testWebServers)
 	suite.Run(t)
 }

smoke/rust_test.go

@@ -0,0 +1,79 @@
+package smoke_test
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/paketo-buildpacks/occam"
+	"github.com/sclevine/spec"
+
+	. "github.com/onsi/gomega"
+	. "github.com/paketo-buildpacks/occam/matchers"
+)
+
+func testRust(t *testing.T, context spec.G, it spec.S) {
+	var (
+		Expect     = NewWithT(t).Expect
+		Eventually = NewWithT(t).Eventually
+
+		pack   occam.Pack
+		docker occam.Docker
+	)
+
+	it.Before(func() {
+		pack = occam.NewPack().WithVerbose().WithNoColor()
+		docker = occam.NewDocker()
+	})
+
+	context("detects a Rust app", func() {
+		var (
+			image     occam.Image
+			container occam.Container
+
+			name   string
+			source string
+		)
+
+		it.Before(func() {
+			var err error
+			name, err = occam.RandomName()
+			Expect(err).NotTo(HaveOccurred())
+		})
+
+		it.After(func() {
+			if container.ID != "" {
+				_ = docker.Container.Remove.Execute(container.ID)
+			}
+			_ = docker.Volume.Remove.Execute(occam.CacheVolumeNames(name))
+			if image.ID != "" {
+				_ = docker.Image.Remove.Execute(image.ID)
+			}
+			Expect(os.RemoveAll(source)).To(Succeed())
+		})
+
+		it("builds successfully", func() {
+			var err error
+			source, err = occam.Source(filepath.Join("testdata", "rust"))
+			Expect(err).NotTo(HaveOccurred())
+
+			var logs fmt.Stringer
+			image, logs, err = pack.Build.
+				WithPullPolicy("always").
+				WithBuilder(Builder).
+				Execute(name, source)
+			Expect(err).ToNot(HaveOccurred(), logs.String)
+
+			container, err = docker.Container.Run.
+				WithEnv(map[string]string{"PORT": "8080"}).
+				WithPublish("8080").
+				Execute(image.ID)
+			Expect(err).NotTo(HaveOccurred())
+
+			Eventually(container).Should(BeAvailable())
+
+			Expect(logs).To(ContainLines(ContainSubstring("Octopilot Rust Buildpack")))
+		})
+	})
+}

smoke/testdata/rust/Cargo.lock

@@ -0,0 +1,7 @@
+[package]
+name = "rust-smoke"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+ctrlc = "3.4"

smoke/testdata/rust/Cargo.toml

@@ -0,0 +1 @@
+Minimal Rust app for builder smoke test. Single crate; no workspace.

smoke/testdata/rust/README.md

@@ -0,0 +1,17 @@
+// Minimal Rust app for buildpack smoke test: listen on PORT and respond.
+use std::env;
+use std::io::Write;
+use std::net::TcpListener;
+use std::process;
+
+fn main() {
+    ctrlc::set_handler(|| process::exit(0)).expect("set signal handler");
+    let port = env::var("PORT").unwrap_or_else(|_| "8080".to_string());
+    let bind = format!("0.0.0.0:{}", port);
+    let listener = TcpListener::bind(&bind).expect("bind");
+    eprintln!("jammy rust test crate starting");
+    eprintln!("port={}", port);
+    for mut stream in listener.incoming().flatten() {
+        let _ = stream.write_all(b"HTTP/1.1 200 OK\r\nContent-Length: 2\r\n\r\nok");
+    }
+}