Trailing slash middleware for the Infrastructure package (#53)

Packages/Infrastructure/Tests/Cases/Public/Middlewares/TrailingSlashRedirectMiddlewareTests.swift

@@ -0,0 +1,150 @@
+import HTTPTypes
+import Hummingbird
+import HummingbirdTesting
+import Testing
+
+@testable import Infrastructure
+
+@Suite(
+    "TrailingSlashRedirectMiddleware middleware",
+    .tags(.middleware)
+)
+struct TrailingSlashRedirectMiddlewareTests {
+
+    // MARK: Functional tests
+
+    @Test
+    func `redirects a path carrying a trailing slash`() async throws {
+        try await app().test(.router) { client in
+            try await client.execute(
+                uri: "/hello/",
+                method: .get
+            ) { response in
+                #expect(response.status == .movedPermanently)
+                #expect(response.headers[.location] == "/hello")
+            }
+        }
+    }
+
+    @Test
+    func `preserves the query of the redirected request`() async throws {
+        try await app().test(.router) { client in
+            try await client.execute(
+                uri: "/hello/?utm_source=test&utm_medium=email",
+                method: .get
+            ) { response in
+                #expect(response.headers[.location] == "/hello?utm_source=test&utm_medium=email")
+            }
+        }
+    }
+
+    @Test
+    func `collapses a path of nothing but slashes onto the root`() async throws {
+        try await app().test(.router) { client in
+            try await client.execute(
+                uri: "//",
+                method: .get
+            ) { response in
+                #expect(response.status == .movedPermanently)
+                #expect(response.headers[.location] == "/")
+            }
+        }
+    }
+
+    @Test
+    func `strips every trailing slash at once`() async throws {
+        try await app().test(.router) { client in
+            try await client.execute(
+                uri: "/hello///",
+                method: .get
+            ) { response in
+                #expect(response.headers[.location] == "/hello")
+            }
+        }
+    }
+
+    @Test
+    func `passes the canonical path through`() async throws {
+        try await app().test(.router) { client in
+            try await client.execute(
+                uri: "/hello",
+                method: .get
+            ) { response in
+                #expect(response.status == .ok)
+                #expect(response.headers[.location] == nil)
+            }
+        }
+    }
+
+    @Test
+    func `leaves the root path alone`() async throws {
+        try await app().test(.router) { client in
+            try await client.execute(
+                uri: "/",
+                method: .get
+            ) { response in
+                #expect(response.status == .ok)
+                #expect(response.headers[.location] == nil)
+            }
+        }
+    }
+
+    @Test
+    func `redirects a head request as it does a get`() async throws {
+        try await app().test(.router) { client in
+            try await client.execute(
+                uri: "/hello/",
+                method: .head
+            ) { response in
+                #expect(response.status == .movedPermanently)
+                #expect(response.headers[.location] == "/hello")
+            }
+        }
+    }
+
+    @Test
+    func `passes a post through so its body survives`() async throws {
+        try await app().test(.router) { client in
+            try await client.execute(
+                uri: "/hello/",
+                method: .post
+            ) { response in
+                #expect(response.status == .ok)
+                #expect(response.headers[.location] == nil)
+            }
+        }
+    }
+
+}
+
+// MARK: - Helpers
+
+private extension TrailingSlashRedirectMiddlewareTests {
+
+    // MARK: Methods
+
+    /// Builds an application whose router applies the trailing-slash middleware ahead of a `/hello`
+    /// route answering both `GET` and `POST`, and a root route standing in for the landing page.
+    func app() -> some ApplicationProtocol {
+        let router = Router()
+
+        router.addMiddleware {
+            TrailingSlashRedirectMiddleware()
+        }
+
+        router.get("hello") { _, _ in
+            "Hello!"
+        }
+
+        router.post("hello") { _, _ in
+            "Posted!"
+        }
+
+        router.get("/") { _, _ in
+            "Root!"
+        }
+
+        return Application(router: router)
+    }
+
+}