Examples: Add an example which uses a resource bundle (#82)

Motivation
----------

An example showing how to use resources (#78) is helpful for new users
and can be used as an end to end tests for this feature.

Modifications
-------------

* Add a new `HelloWorldWithResources` example
* Add the new example to the `End to end tests` GitHub Actions job
* Restructure the end to end tests to check the HTTP response code
instead of the content which is returned, because the new test returns
one of 3 JPEGs selected at random, whereas the existing tests returned
strings.
* Adopt the code structure used by the [official Hummingbird
examples](https://github.com/hummingbird-project/hummingbird-examples),
to make it more familiar to users who are used to the official examples.
 
Result
------

* The repository contains a new example showing how to use resources in
a container image
* The resource feature is tested as part of the automated end to end
test suite.

Test Plan
---------

The new test passes and all existing tests continue to pass.

Author: euanh

.github/workflows/endtoend_tests.yml

@@ -21,6 +21,7 @@ jobs:
                 example:
                     - Examples/HelloWorldVapor
                     - Examples/HelloWorldHummingbird
+                    - Examples/HelloWorldWithResources
         steps:
             - name: Checkout repository
               uses: actions/checkout@v4
@@ -55,4 +56,14 @@ jobs:
 
             - name: Check that the service is running
               run: |
-                  curl -v localhost:8080 | grep "Hello World"
+                  # The curious combination of --verbose and --silent causes
+                  # curl to print the request and response (--verbose) but not
+                  # the transmission progress messages (--silent).
+                  #
+                  # --fail-with-body causes curl to exit with a nonzero exit code
+                  # if the HTTP response code is >= 400.   Without this flag, curl
+                  # only returns a nonzero exit code if something went wrong while
+                  # connecting to the server - a successful HTTP transaction which
+                  # indicates a server error is still considered to be a successful
+                  # transaction from the client's point of view.
+                  curl --verbose --silent --output /dev/null --fail-with-body localhost:8080

.licenseignore

@@ -1,4 +1,5 @@
 **/*.docc/*
+**/*.jpg
 **/*.md
 **/.gitignore
 **/Package.resolved

Examples/HelloWorldWithResources/Package.swift

@@ -0,0 +1,37 @@
+// swift-tools-version: 6.0
+
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the SwiftContainerPlugin open source project
+//
+// Copyright (c) 2025 Apple Inc. and the SwiftContainerPlugin project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of SwiftContainerPlugin project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+import PackageDescription
+
+let package = Package(
+    name: "hello-world",
+    platforms: [.macOS(.v14)],
+    dependencies: [
+        .package(url: "https://github.com/hummingbird-project/hummingbird.git", from: "2.1.0"),
+        .package(url: "https://github.com/apple/swift-container-plugin", from: "0.5.0"),
+        .package(url: "https://github.com/apple/swift-argument-parser", from: "1.3.0"),
+    ],
+    targets: [
+        .executableTarget(
+            name: "hello-world",
+            dependencies: [
+                .product(name: "Hummingbird", package: "hummingbird"),
+                .product(name: "ArgumentParser", package: "swift-argument-parser"),
+            ],
+            resources: [.process("resources")]
+        )
+    ]
+)

Examples/HelloWorldWithResources/Sources/App.swift

@@ -0,0 +1,34 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the SwiftContainerPlugin open source project
+//
+// Copyright (c) 2025 Apple Inc. and the SwiftContainerPlugin project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of SwiftContainerPlugin project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+import ArgumentParser
+
+@main
+struct Hello: AsyncParsableCommand {
+    @Option(name: .shortAndLong)
+    var hostname: String = "0.0.0.0"
+
+    @Option(name: .shortAndLong)
+    var port: Int = 8080
+
+    func run() async throws {
+        let app = buildApplication(
+            configuration: .init(
+                address: .hostname(hostname, port: port),
+                serverName: "Hummingbird"
+            )
+        )
+        try await app.runService()
+    }
+}

Examples/HelloWorldWithResources/Sources/Application+build.swift

@@ -0,0 +1,51 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the SwiftContainerPlugin open source project
+//
+// Copyright (c) 2025 Apple Inc. and the SwiftContainerPlugin project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of SwiftContainerPlugin project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+import Foundation
+import Hummingbird
+import Logging
+
+let myos = ProcessInfo.processInfo.operatingSystemVersionString
+
+func buildApplication(configuration: ApplicationConfiguration) -> some ApplicationProtocol {
+    let router = Router()
+    router.addMiddleware { LogRequestsMiddleware(.info) }
+    router.get("/") { _, _ in
+        let faces = [
+            "happy-cat-face",
+            "slightly-smiling-face",
+            "smiling-face-with-sunglasses",
+        ]
+
+        guard let resourceURL = Bundle.module.url(forResource: faces.randomElement(), withExtension: "jpg") else {
+            throw HTTPError(.internalServerError)
+        }
+
+        let image = try Data(contentsOf: resourceURL)
+
+        return Response(
+            status: .ok,
+            headers: [.contentType: "image/jpg"],
+            body: .init(byteBuffer: ByteBuffer(bytes: image))
+        )
+    }
+
+    let app = Application(
+        router: router,
+        configuration: configuration,
+        logger: Logger(label: "hello-with-resources")
+    )
+
+    return app
+}