Localization support for the Website service (#10)

This PR contains the work done to introduce server-side localization support to the **Website** service so the landing and error pages are served in the visitor's negotiated language, backed by a new reusable Localization package.

To provide further details about the work:

* Created the _Localization_ package — a bundle-bound `Localize` method and a `LanguageList` type.
* Language negotiation — `NegotiateLanguage` method picks the best supported language from the request's _Accept-Language_ header (falling back to the default); the `LocalizationMiddleware` middleware resolves it per request and stores it on a new `LocalizedRequestContext` / `WebsiteRequestContext` context.
* Localized responses — `LocalizedHTMLCollectionResponse` pre-renders each page once per language and caches the bytes (with `Content-Language` + `Vary: Accept-Language`), reused by the  `RootController` controller and `NotFoundMiddleware` middleware.
* The `CachedHTMLResponse` response gained custom-header support.
* Localized pages — the `IndexPage` and `ErrorPage` pages now resolve their strings via `Localize` method;
* Added `Localizable.xcstrings` catalogs.
* Wired the `LocalizationMiddleware` middlewaer into the router.

Reviewed-on: rock-n-code/loud-amsterdam#10
Co-authored-by: Javier Cicchelli <javier@rock-n-code.com>
Co-committed-by: Javier Cicchelli <javier@rock-n-code.com>
This commit is contained in:
2026-06-29 23:08:36 +00:00
committed by javier
parent 847058d642
commit 6c66ea74cc
24 changed files with 858 additions and 49 deletions
@@ -0,0 +1,77 @@
<?xml version="1.0" encoding="UTF-8"?>
<Scheme
LastUpgradeVersion = "2700"
version = "1.7">
<BuildAction
parallelizeBuildables = "YES"
buildImplicitDependencies = "YES"
buildArchitectures = "Automatic">
<BuildActionEntries>
<BuildActionEntry
buildForTesting = "YES"
buildForRunning = "YES"
buildForProfiling = "YES"
buildForArchiving = "YES"
buildForAnalyzing = "YES">
<BuildableReference
BuildableIdentifier = "primary"
BlueprintIdentifier = "Localization"
BuildableName = "Localization"
ReferencedContainer = "container:">
</BuildableReference>
</BuildActionEntry>
</BuildActionEntries>
</BuildAction>
<TestAction
buildConfiguration = "Debug"
selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
shouldUseLaunchSchemeArgsEnv = "YES"
shouldAutocreateTestPlan = "YES">
<Testables>
<TestableReference
skipped = "NO">
<BuildableReference
BuildableIdentifier = "primary"
BlueprintIdentifier = "LocalizationTests"
BuildableName = "LocalizationTests"
ReferencedContainer = "container:">
</BuildableReference>
</TestableReference>
</Testables>
</TestAction>
<LaunchAction
buildConfiguration = "Debug"
selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
launchStyle = "0"
useCustomWorkingDirectory = "NO"
ignoresPersistentStateOnLaunch = "NO"
debugDocumentVersioning = "YES"
debugServiceExtension = "internal"
allowLocationSimulation = "YES"
queueDebuggingEnabled = "No">
</LaunchAction>
<ProfileAction
buildConfiguration = "Release"
shouldUseLaunchSchemeArgsEnv = "YES"
savedToolIdentifier = ""
useCustomWorkingDirectory = "NO"
debugDocumentVersioning = "YES">
<MacroExpansion>
<BuildableReference
BuildableIdentifier = "primary"
BlueprintIdentifier = "Localization"
BuildableName = "Localization"
ReferencedContainer = "container:">
</BuildableReference>
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</ProfileAction>
<AnalyzeAction
buildConfiguration = "Debug">
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buildConfiguration = "Release"
revealArchiveInOrganizer = "YES">
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</Scheme>
+37
View File
@@ -0,0 +1,37 @@
// swift-tools-version:6.3
import PackageDescription
let package = Package(
name: "Localization",
defaultLocalization: "en",
platforms: [
.macOS(.v15),
.iOS(.v18),
.tvOS(.v18),
],
products: [
.library(
name: "Localization",
targets: [
"Localization"
]
)
],
targets: [
.target(
name: "Localization",
path: "Sources",
),
.testTarget(
name: "LocalizationTests",
dependencies: [
.byName(name: "Localization")
],
path: "Tests",
resources: [
.process("Catalogs/Localizable.xcstrings")
]
),
]
)
@@ -0,0 +1,45 @@
import Foundation
/// A reusable, bundle-bound localizer that resolves String Catalog entries for an explicit locale.
///
/// A server has no single "current" locale, so each lookup must name the locale to use. An instance
/// is bound to the bundle whose catalog holds the strings, then invoked like a function to resolve a
/// key in a chosen locale.
public struct Localize: Sendable {
// MARK: Properties
/// The bundle whose compiled String Catalog the keys are resolved against.
private let bundle: Bundle
// MARK: Initializers
/// Creates a localizer backed by the given bundle.
/// - Parameter bundle: the bundle whose String Catalog contains the keys to resolve.
public init(
bundle: Bundle
) {
self.bundle = bundle
}
// MARK: Methods
/// Resolves a catalog key in the given locale.
///
/// Invoked by calling the instance directly, for example `localize("index.title", locale: locale)`.
/// - Parameters:
/// - key: the String Catalog key to look up.
/// - locale: the locale to resolve the key in.
/// - Returns: the localized string for the locale, or the key itself when the bundle's catalog has no entry for it.
public func callAsFunction(
_ key: String.LocalizationValue,
locale: Locale
) -> String {
.init(localized: .init(
key,
locale: locale,
bundle: .atURL(bundle.bundleURL)
))
}
}
@@ -0,0 +1,46 @@
import Foundation
/// The list of languages an app can serve, derived from a bundle's String Catalog.
///
/// The languages are read from the injected `bundle`'s compiled localizations, so the catalog that
/// ships in that bundle is the single source of truth: adding a language is a translation-only
/// change once a locale exists in the catalog, it appears in ``all`` with no code change required.
public struct LanguageList: Sendable {
// MARK: Properties
/// The language served when none of the supported languages match a request.
///
/// Should match the catalog bundle's development localization.
public let `default`: String
/// The bundle whose compiled String Catalog defines the available languages.
private let bundle: Bundle
// MARK: Initializers
/// Creates a language list backed by the given bundle.
/// - Parameters:
/// - bundle: the bundle whose String Catalog defines the available languages.
/// - default: the language served when none of the supported languages match. Defaults to `"en"`.
public init(
bundle: Bundle,
`default`: String = "en"
) {
self.bundle = bundle
self.`default` = `default`
}
// MARK: Computed
/// Every language the bundle's String Catalog provides a localization for.
///
/// The `Base` internationalization is excluded, as it is a development placeholder rather than a
/// real language.
public var all: [String] {
bundle
.localizations
.filter { $0 != "Base" }
}
}
@@ -0,0 +1,45 @@
import Foundation
import Testing
@testable import Localization
@Suite("Localize method")
struct LocalizeTests {
// MARK: Constants
private let localize = Localize(bundle: .module)
// MARK: Functional tests
@Test
func `resolves a key in the default locale`() {
let text = localize(
"test.greeting",
locale: Locale(identifier: "en")
)
#expect(text == "Hello")
}
@Test
func `resolves a key in another locale`() {
let text = localize(
"test.greeting",
locale: Locale(identifier: "de"),
)
#expect(text == "Hallo")
}
@Test
func `falls back to the key for an unknown entry`() {
let text = localize(
"unknown.key",
locale: Locale(identifier: "en"),
)
#expect(text == "unknown.key")
}
}
@@ -0,0 +1,65 @@
import Foundation
import Testing
@testable import Localization
@Suite("LanguageList type")
struct LanguageListTests {
// MARK: Properties tests
@Suite("default")
struct Default {
@Test
func `defaults to english`() {
let list = LanguageList(
bundle: .module
)
#expect(list.default == "en")
}
@Test
func `uses the provided default language`() {
let list = LanguageList(
bundle: .module,
default: "de"
)
#expect(list.default == "de")
}
}
@Suite("all")
struct All {
@Test
func `lists the catalog languages`() {
let list = LanguageList(
bundle: .module
)
#expect(list.all.contains("en"))
#expect(list.all.contains("de"))
}
@Test
func `excludes the base localization`() {
let list = LanguageList(
bundle: .module
)
#expect(!list.all.contains("Base"))
}
@Test
func `lists each language only once`() {
let list = LanguageList(
bundle: .module
)
let all = list.all
#expect(all.count == Set(all).count)
}
}
}
@@ -0,0 +1,23 @@
{
"sourceLanguage" : "en",
"strings" : {
"test.greeting" : {
"comment" : "Fixture string used by the Localization test suite.",
"localizations" : {
"de" : {
"stringUnit" : {
"state" : "translated",
"value" : "Hallo"
}
},
"en" : {
"stringUnit" : {
"state" : "translated",
"value" : "Hello"
}
}
}
}
},
"version" : "1.0"
}
+9 -1
View File
@@ -4,6 +4,7 @@ import PackageDescription
let package = Package(
name: "Website",
defaultLocalization: "en",
platforms: [
.macOS(.v15),
.iOS(.v18),
@@ -19,6 +20,9 @@ let package = Package(
)
],
dependencies: [
.package(
path: "../Packages/Localization"
),
.package(
url: "https://github.com/elementary-swift/elementary.git",
from: "0.6.0"
@@ -67,6 +71,7 @@ let package = Package(
.target(
name: "WebsiteCore",
dependencies: [
.byName(name: "Localization"),
.product(
name: "Configuration",
package: "swift-configuration"
@@ -84,7 +89,10 @@ let package = Package(
package: "hummingbird-elementary"
),
],
path: "Sources/Library"
path: "Sources/Library",
resources: [
.process("Catalogs/Localizable.xcstrings")
]
),
.testTarget(
name: "WebsiteTests",
+4 -2
View File
@@ -69,7 +69,7 @@ func application(
// MARK: - Helpers
// Request context used by application
private typealias AppRequestContext = BasicRequestContext
private typealias AppRequestContext = WebsiteRequestContext
/// Builds the cache-control policy applied to the served static files.
///
@@ -153,7 +153,8 @@ private func logger(
/// Registers the request-logging middleware, the security-headers middleware that stamps the given
/// `securityHeaders` onto every response, the response-compression middleware that compresses
/// responses larger than `minimumResponseSizeToCompress` when the client advertises support, the
/// not-found middleware that serves the error page, and the static file middleware that serves the
/// localization middleware that negotiates the request's language from its `Accept-Language` header,
/// the not-found middleware that serves the error page, and the static file middleware that serves the
/// contents of `staticFilesPath` (tagging responses with the given `cacheControl` directives), then
/// adds the `RootController` routes that render the landing page and the `HealthController` routes
/// that serve the health check.
@@ -185,6 +186,7 @@ private func router(
ResponseCompressionMiddleware(
minimumResponseSizeToCompress: compressionMinResponseSize
)
LocalizationMiddleware()
NotFoundMiddleware()
FileMiddleware(
staticFilesPath,
@@ -0,0 +1,61 @@
{
"sourceLanguage" : "en",
"strings" : {
"error.heading" : {
"comment" : "The not-found page's main heading.",
"localizations" : {
"en" : {
"stringUnit" : {
"state" : "translated",
"value" : "Page Not Found"
}
}
}
},
"error.message" : {
"comment" : "The not-found page's body text.",
"localizations" : {
"en" : {
"stringUnit" : {
"state" : "translated",
"value" : "Sorry, but the page you were trying to view does not exist."
}
}
}
},
"error.title" : {
"comment" : "The not-found page's document title.",
"localizations" : {
"en" : {
"stringUnit" : {
"state" : "translated",
"value" : "Page Not Found"
}
}
}
},
"index.greeting" : {
"comment" : "The landing page's greeting paragraph.",
"localizations" : {
"en" : {
"stringUnit" : {
"state" : "translated",
"value" : "Hello world! This is HTML5 Boilerplate."
}
}
}
},
"index.title" : {
"comment" : "The landing page's document title.",
"localizations" : {
"en" : {
"stringUnit" : {
"state" : "translated",
"value" : "Index page"
}
}
}
}
},
"version" : "1.0"
}
@@ -0,0 +1,85 @@
import Foundation
import Localization
/// Negotiates the best supported language for a request from its `Accept-Language` header.
///
/// Bound to the module's catalog languages via ``LanguageList``, an instance is invoked like a
/// function through ``callAsFunction(forAcceptLanguage:)`` to resolve a header value to a
/// supported language identifier, falling back to the default language.
struct NegotiateLanguage {
// MARK: Properties
/// The supported languages and default language, derived from the module's String Catalog.
private let list: LanguageList
// MARK: Initializers
/// Creates a language negotiator backed by the module's String Catalog.
init() {
self.list = .init(bundle: .module)
}
// MARK: Methods
/// Picks the best supported language for the given `Accept-Language` header value.
///
/// Invoked by calling the instance directly, for example `negotiate(forAcceptLanguage: header)`.
/// The header is split into its language tags (dropping any `q` weights), then matched against
/// the supported languages with `Bundle.preferredLocalizations(from:forPreferences:)`. When the
/// header is absent or matches nothing, the default language is returned.
/// - Parameter acceptLanguage: the raw `Accept-Language` header value, if any.
/// - Returns: the identifier of the supported language to serve.
func callAsFunction(
forAcceptLanguage acceptLanguage: String?
) -> String {
guard let acceptLanguage else {
return list.default
}
let tags = tags(from: acceptLanguage)
guard !tags.isEmpty else {
return list.default
}
let preferred = Bundle.preferredLocalizations(
from: list.all,
forPreferences: tags
)
return preferred.first
?? list.default
}
}
// MARK: - Helpers
private extension NegotiateLanguage {
// MARK: Methods
/// Extracts the ordered language tags from an `Accept-Language` header value.
///
/// Each comma-separated entry is reduced to its language tag by dropping the `;q=` weight, and
/// blank entries are removed. The original order is kept, which mirrors descending preference
/// closely enough for `preferredLocalizations(from:forPreferences:)` to resolve correctly.
/// - Parameter acceptLanguage: the raw `Accept-Language` header value.
/// - Returns: the ordered, weight-stripped language tags.
func tags(
from acceptLanguage: String
) -> [String] {
acceptLanguage
.split(separator: ",")
.map { entry in
entry
.split(separator: ";")
.first
.map(String.init)?
.trimmingCharacters(in: .whitespaces) ?? ""
}
.filter { !$0.isEmpty }
}
}
@@ -1,14 +1,39 @@
import Elementary
import Foundation
import Localization
/// The HTML page rendered for a not-found response.
/// The HTML page rendered for a not-found response, with its text localized to a given locale.
struct ErrorPage: HTMLDocument, Sendable {
// MARK: Properties
/// The locale the page content is localized to.
private let locale: Locale
/// Resolves the page's text from the bundled String Catalog for the page's ``locale``.
private let localize: Localize
// MARK: Initializers
/// Creates a not-found page localized to the given locale.
/// - Parameter locale: the locale the page content is localized to.
init(
locale: Locale
) {
self.locale = locale
self.localize = .init(bundle: .module)
}
// MARK: Document
/// The page's content.
/// The page's content: a localized heading and explanatory message.
var body: some HTML {
h1 { "Page Not Found" }
p { "Sorry, but the page you were trying to view does not exist." }
h1 {
localize("error.heading", locale: locale)
}
p {
localize("error.message", locale: locale)
}
}
/// The metadata and stylesheet link placed in the document head.
@@ -24,10 +49,15 @@ struct ErrorPage: HTMLDocument, Sendable {
)
}
/// The document language.
var lang: String { "en" }
/// The document language, derived from the page's locale and falling back to the default language.
var lang: String {
locale.language.languageCode?.identifier
?? LanguageList(bundle: .module).default
}
/// The document title.
var title: String { "Page Not Found" }
/// The localized document title.
var title: String {
localize("error.title", locale: locale)
}
}
@@ -1,13 +1,36 @@
import Elementary
import Foundation
import Localization
/// The website's landing page.
/// The website's landing page, with its text localized to a given locale.
struct IndexPage: HTMLDocument, Sendable {
// MARK: Properties
/// The locale the page content is localized to.
private let locale: Locale
/// Resolves the page's text from the bundled String Catalog for the page's ``locale``.
private let localize: Localize
// MARK: Initializers
/// Creates a landing page localized to the given locale.
/// - Parameter locale: the locale the page content is localized to.
init(
locale: Locale
) {
self.locale = locale
self.localize = .init(bundle: .module)
}
// MARK: Document
/// The page's content.
/// The page's content: a localized greeting followed by the app script.
var body: some HTML {
p { "Hello world! This is HTML5 Boilerplate." }
p {
localize("index.greeting", locale: locale)
}
script(.src("/js/app.js")) {}
}
@@ -52,14 +75,15 @@ struct IndexPage: HTMLDocument, Sendable {
)
}
/// The document language.
/// The document language, derived from the page's locale and falling back to the default language.
var lang: String {
"en"
locale.language.languageCode?.identifier
?? LanguageList(bundle: .module).default
}
/// The document title.
/// The localized document title.
var title: String {
"Index page"
localize("index.title", locale: locale)
}
}
@@ -1,12 +1,16 @@
import Elementary
import HTTPTypes
import Hummingbird
import NIOCore
/// A pre-rendered HTTP response for a fully static HTML page.
///
/// The document is rendered to bytes once, at initialization, and every ``response()`` reuses those
/// bytes instead of re-rendering. This suits pages whose markup never changes between requests the
/// landing page and the not-found page avoiding a per-request Elementary render on hot paths.
/// bytes along with a fixed status and precomputed headers instead of re-rendering. This suits
/// pages whose markup never changes between requests, such as the landing page and the not-found
/// page, avoiding a per-request Elementary render on hot paths.
///
/// ``LocalizedHTMLResponses`` builds on this type, caching one instance per supported language.
///
/// The body is written as an unsized stream (no `Content-Length`), mirroring `HTMLResponse`, so the
/// response-compression middleware downstream treats it exactly as it would a freshly rendered page.
@@ -14,23 +18,37 @@ struct CachedHTMLResponse: Sendable {
// MARK: Properties
/// The status applied to every response.
private let status: HTTPResponse.Status
/// The page rendered to bytes once.
private let buffer: ByteBuffer
/// The headers applied to every response, precomputed once.
private let headers: HTTPFields
/// The status applied to every response.
private let status: HTTPResponse.Status
// MARK: Initializers
/// Renders the given document to bytes once.
/// - Parameters:
/// - status: the status applied to every response. Defaults to `.ok`.
/// - additionalHeaders: extra headers merged onto every response, alongside the content type.
/// Used to carry per-language signals such as `Content-Language` and `Vary`.
/// - document: the static HTML document to render and cache.
init(
status: HTTPResponse.Status = .ok,
_ document: some HTMLDocument
additionalHeaders: HTTPFields = [:],
document: some HTMLDocument
) {
var headers: HTTPFields = [
.contentType: "text/html; charset=utf-8"
]
for field in additionalHeaders {
headers[field.name] = field.value
}
self.status = status
self.buffer = ByteBuffer(string: document.render())
self.headers = headers
self.buffer = .init(string: document.render())
}
// MARK: Methods
@@ -43,7 +61,7 @@ struct CachedHTMLResponse: Sendable {
func response() -> Response {
Response(
status: status,
headers: [.contentType: "text/html; charset=utf-8"],
headers: headers,
body: .init { [buffer] writer in
try await writer.write(buffer)
try await writer.finish(nil)
@@ -0,0 +1,65 @@
import Elementary
import Foundation
import HTTPTypes
import Hummingbird
import Localization
/// A per-language collection of pre-rendered HTML responses.
///
/// At initialization it renders the document once for each language the bundle's ``LanguageList``
/// reports and caches the bytes, mirroring ``CachedHTMLResponse``'s render-once model but keyed by
/// language. Each cached response carries a `Content-Language` header and `Vary: Accept-Language`, so
/// shared caches key on the negotiated language instead of serving one language to everyone.
struct LocalizedHTMLCollectionResponse: Sendable {
// MARK: Properties
/// The supported languages and default language, derived from the module's String Catalog.
private let list: LanguageList
/// The pre-rendered responses, keyed by language identifier.
private let responses: [String: CachedHTMLResponse]
// MARK: Initializers
/// Renders the document once per supported language.
/// - Parameters:
/// - status: the status applied to every response. Defaults to `.ok`.
/// - document: builds the document to render for a given locale.
init<Document: HTMLDocument>(
status: HTTPResponse.Status = .ok,
document: (Locale) -> Document
) {
self.list = .init(bundle: .module)
self.responses = list.all
.reduce(into: [:]) { responses, language in
responses[language] = CachedHTMLResponse(
status: status,
additionalHeaders: [
.contentLanguage: language,
.vary: "Accept-Language",
],
document: document(.init(identifier: language))
)
}
}
// MARK: Methods
/// Builds the response for the given language, falling back to the default language.
/// - Parameter language: the negotiated language identifier.
/// - Returns: the cached response for the language, the default language's response when the
/// language is unavailable, or a `500 Internal Server Error` if neither is cached.
func response(
for language: String
) -> Response {
guard
let response = responses[language] ?? responses[list.default]
else {
return .init(status: .internalServerError)
}
return response.response()
}
}
@@ -0,0 +1,42 @@
import Hummingbird
import Localization
/// A request context that carries the language negotiated for the request.
///
/// ``LocalizationMiddleware`` resolves the visitor's preferred language from the `Accept-Language`
/// header and stores it here, so downstream controllers and middleware can serve the matching
/// localization without re-reading the header.
public protocol LocalizedRequestContext: RequestContext {
// MARK: Properties
/// The language identifier negotiated for the request.
var language: String { get set }
}
// MARK: - Context
/// The website's request context.
///
/// Extends the core request storage with the negotiated language, defaulting to the default
/// supported language until ``LocalizationMiddleware`` resolves it from the request.
public struct WebsiteRequestContext: LocalizedRequestContext {
// MARK: Properties
/// The core request context storage Hummingbird requires.
public var coreContext: CoreRequestContextStorage
/// The language identifier negotiated for the request.
public var language: String
// MARK: Initializers
/// Creates a request context for the given source.
/// - Parameter source: the source the context is initialized from.
public init(source: Source) {
self.coreContext = .init(source: source)
self.language = LanguageList(bundle: .module).default
}
}
@@ -11,25 +11,26 @@ import Hummingbird
///
/// - Note: `Context` is the request context the routes are resolved against, and must match the
/// context of the router the routes are added to.
public struct RootController<Context: RequestContext>: Sendable {
public struct RootController<Context: LocalizedRequestContext>: Sendable {
// MARK: Properties
/// The landing page, rendered once at initialization and reused for every request.
private let cache: CachedHTMLResponse
/// The landing page, rendered once per supported language and reused for every request.
private let responses: LocalizedHTMLCollectionResponse
// MARK: Initializers
/// Creates a root controller.
public init() {
self.cache = .init(IndexPage())
self.responses = .init { IndexPage(locale: $0) }
}
// MARK: Computed
/// The routes served by the controller.
///
/// Serves a `GET` request for the root path (`/`) by rendering the ``IndexPage``.
/// Serves a `GET` request for the root path (`/`) by rendering the ``IndexPage`` in the
/// language negotiated for the request.
public var routes: RouteCollection<Context> {
let routes = RouteCollection(context: Context.self)
@@ -50,16 +51,19 @@ private extension RootController {
// MARK: Methods
/// Handles a request for the landing page.
///
/// Renders the ``IndexPage`` in the language stored on the context by ``LocalizationMiddleware``,
/// falling back to the default language.
/// - Parameters:
/// - request: the incoming request.
/// - context: the context the request is resolved against.
/// - Returns: the cached ``IndexPage`` response.
/// - Returns: the cached ``IndexPage`` response for the context's language.
@Sendable
func index(
request: Request,
context: some RequestContext
context: Context
) -> Response {
cache.response()
responses.response(for: context.language)
}
}
@@ -0,0 +1,56 @@
import HTTPTypes
import Hummingbird
import Localization
/// Resolves the visitor's preferred language and records it on the request context.
///
/// Placed ahead of the localized responders in the middleware chain, it reads the request's
/// `Accept-Language` header, negotiates the best supported match (falling back to the default
/// language), and stores it on the context's ``LocalizedRequestContext/language``.
///
/// The request is otherwise passed through untouched the URL and routing are not affected so
/// each page is served at its existing path and varies its content by header.
public struct LocalizationMiddleware<Context: LocalizedRequestContext> {
// MARK: Properties
/// Negotiates the request's language from its `Accept-Language` header.
private let negotiate: NegotiateLanguage
// MARK: Initializers
/// Creates a localization middleware.
public init() {
self.negotiate = .init()
}
}
// MARK: - RouterMiddleware
extension LocalizationMiddleware: RouterMiddleware {
// MARK: Functions
/// Negotiates the request's language and records it on the context before passing it down.
/// - Parameters:
/// - request: the incoming request.
/// - context: the context the request is resolved against.
/// - next: the next responder in the middleware chain.
/// - Returns: the downstream response.
/// - Throws: any error thrown downstream.
public func handle(
_ request: Request,
context: Context,
next: (Request, Context) async throws -> Response
) async throws -> Response {
var context = context
context.language = negotiate(
forAcceptLanguage: request.headers[.acceptLanguage]
)
return try await next(request, context)
}
}
@@ -4,22 +4,24 @@ import Hummingbird
///
/// Placed ahead of `FileMiddleware` in the middleware chain, it catches the `.notFound` error
/// that bubbles up when no file exists for the requested path and responds with the rendered
/// ``ErrorPage`` and a `404 Not Found` status.
public struct NotFoundMiddleware<Context: RequestContext> {
/// ``ErrorPage`` and a `404 Not Found` status. The page is served in the language stored on the
/// context by ``LocalizationMiddleware``, falling back to the default language.
public struct NotFoundMiddleware<Context: LocalizedRequestContext> {
// MARK: Properties
/// The error page, rendered once at initialization and reused for every not-found response.
private let cache: CachedHTMLResponse
/// The error page, rendered once per supported language and reused for every not-found response.
private let responses: LocalizedHTMLCollectionResponse
// MARK: Initializers
/// Creates a not-found middleware.
public init() {
self.cache = .init(
status: .notFound,
ErrorPage()
)
self.responses = .init(
status: .notFound
) {
ErrorPage(locale: $0)
}
}
}
@@ -56,7 +58,9 @@ extension NotFoundMiddleware: RouterMiddleware {
throw error
}
return cache.response()
return responses.response(
for: context.language
)
}
}
@@ -1,4 +1,5 @@
import Elementary
import Foundation
import Testing
@testable import WebsiteCore
@@ -10,11 +11,14 @@ struct ErrorPageTests {
@Test
func `renders its markup`() {
let html = ErrorPage().render()
let html = ErrorPage(
locale: .init(identifier: "en")
).render()
#expect(html.contains("<!DOCTYPE html>"))
#expect(html.contains(#"lang="en""#))
#expect(html.contains("Page Not Found"))
#expect(html.contains("does not exist"))
#expect(html.contains("Sorry, but the page you were trying to view does not exist."))
#expect(html.contains("/css/error.css"))
}
@@ -1,4 +1,5 @@
import Elementary
import Foundation
import Testing
@testable import WebsiteCore
@@ -10,9 +11,12 @@ struct IndexPageTests {
@Test
func `renders its markup`() {
let html = IndexPage().render()
let html = IndexPage(
locale: .init(identifier: "en")
).render()
#expect(html.contains("<!DOCTYPE html>"))
#expect(html.contains(#"lang="en""#))
#expect(html.contains("/css/style.css"))
#expect(html.contains("/favicon.ico"))
#expect(html.contains("/icon.svg"))
@@ -11,9 +11,13 @@ struct RootControllerTests {
// MARK: Constants
private let app: Application = .init(router: {
let router = Router()
router.addRoutes(RootController<BasicRequestContext>().routes)
let router = Router(context: WebsiteRequestContext.self)
router.addMiddleware {
LocalizationMiddleware()
}
router.addRoutes(RootController<WebsiteRequestContext>().routes)
return router
}())
@@ -31,6 +35,8 @@ struct RootControllerTests {
#expect(response.status == .ok)
#expect(response.headers[.contentType] == "text/html; charset=utf-8")
#expect(response.headers[.contentLanguage] == "en")
#expect(response.headers[.vary] == "Accept-Language")
#expect(body.contains("Hello world!"))
}
}
@@ -0,0 +1,55 @@
import HTTPTypes
import Hummingbird
import HummingbirdTesting
import NIOCore
import Testing
@testable import WebsiteCore
@Suite("LocalizationMiddleware middleware")
struct LocalizationMiddlewareTests {
// MARK: Constants
private let app: Application = .init(router: {
let router = Router(context: WebsiteRequestContext.self)
router.addMiddleware {
LocalizationMiddleware()
}
router.get("language") { _, context in
context.language
}
return router
}())
// MARK: Functional tests
@Test
func `negotiates a supported language from the header`() async throws {
try await app.test(.router) { client in
try await client.execute(
uri: "/language",
method: .get,
headers: [.acceptLanguage: "en-US,en;q=0.9"]
) { response in
#expect(String(buffer: response.body) == "en")
}
}
}
@Test
func `falls back to the default without a header`() async throws {
try await app.test(.router) { client in
try await client.execute(
uri: "/language",
method: .get
) { response in
#expect(String(buffer: response.body) == "en")
}
}
}
}
@@ -11,9 +11,10 @@ struct NotFoundMiddlewareTests {
// MARK: Constants
private let app: Application = .init(router: {
let router = Router()
let router = Router(context: WebsiteRequestContext.self)
router.addMiddleware {
LocalizationMiddleware()
NotFoundMiddleware()
}
@@ -41,6 +42,8 @@ struct NotFoundMiddlewareTests {
#expect(response.status == .notFound)
#expect(response.headers[.contentType] == "text/html; charset=utf-8")
#expect(response.headers[.contentLanguage] == "en")
#expect(response.headers[.vary] == "Accept-Language")
#expect(body.contains("Page Not Found"))
}
}