Shared HTML template for the Website service (#22)

This PR contains the work done to define a `Page` protocol that extracts the HTML scaffolding that `IndexPage` and `ErrorPage` pages duplicated, so every page of the website declares only what makes it unique — its content, title, and assets — while the document structure lives in one place. Also cleans up imports across the workspace.

Reviewed-on: rock-n-code/loud-amsterdam#22
Co-authored-by: Javier Cicchelli <javier@rock-n-code.com>
Co-committed-by: Javier Cicchelli <javier@rock-n-code.com>

Packages/Persistence/Tests/Cases/Public/Methods/ProbeTests.swift

@@ -1,7 +1,6 @@
 import FluentKit
 import HummingbirdFluent
 import Logging
-import NIOCore
 import Testing
 
 @testable import Persistence

Packages/Web/Tests/Cases/Public/Extensions/RouterMethods+RouteCollectionsTests.swift

@@ -1,5 +1,6 @@
 import Hummingbird
 import HummingbirdTesting
+import NIOCore
 import Testing
 
 @testable import Web

Services/Website/Sources/App/App.swift

@@ -1,6 +1,5 @@
 import Configuration
 import Hummingbird
-import Logging
 
 /// The entry point of the website executable.
 ///

Services/Website/Sources/App/Extensions/App+Build.swift

@@ -3,6 +3,7 @@ import Hummingbird
 import HummingbirdCompression
 import Logging
 import Persistence
+import Web
 import WebsiteLibrary
 
 /// Builds the website application.

Services/Website/Sources/Library/Internal/Pages/ErrorPage.swift

@@ -3,12 +3,12 @@ import Foundation
 import Localization
 
 /// The HTML page rendered for a not-found response, with its text localized to a given locale.
-struct ErrorPage: HTMLDocument, Sendable {
+struct ErrorPage {
 
     // MARK: Properties
 
     /// The locale the page content is localized to.
-    private let locale: Locale
+    let locale: Locale
 
     /// Resolves the page's text from the bundled String Catalog for the page's ``locale``.
     private let localize: Localize
@@ -23,45 +23,31 @@ struct ErrorPage: HTMLDocument, Sendable {
         self.locale = locale
         self.localize = .init(bundle: .module)
     }
+}
 
-    // MARK: Document
+// MARK: Page
 
-    /// The page's content: a localized heading and explanatory message, followed by the error and shared scripts.
-    var body: some HTML {
+extension ErrorPage: Page {
+
+    // MARK: Properties
+
+    var content: some HTML {
         h1 {
             localize("error.heading", locale: locale)
         }
         p {
             localize("error.message", locale: locale)
         }
-        script(.src(StaticFile.error.urlPath(for: .js))) {}
-        script(.src(StaticFile.shared.urlPath(for: .js))) {}
     }
 
-    /// The metadata and stylesheet links placed in the document head.
-    var head: some HTML {
-        meta(.charset(.utf8))
-        meta(
-            .name(.viewport),
-            .content("width=device-width, initial-scale=1")
-        )
-        link(
-            .rel(.stylesheet),
-            .href(StaticFile.shared.urlPath(for: .css))
-        )
-        link(
-            .rel(.stylesheet),
-            .href(StaticFile.error.urlPath(for: .css))
-        )
+    var scripts: [StaticFile] {
+        [.error, .shared]
     }
 
-    /// 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
+    var stylesheets: [StaticFile] {
+        [.shared, .error]
     }
 
-    /// The localized document title.
     var title: String {
         localize("error.title", locale: locale)
     }

Services/Website/Sources/Library/Internal/Pages/IndexPage.swift

@@ -3,12 +3,12 @@ import Foundation
 import Localization
 
 /// The website's landing page, with its text localized to a given locale.
-struct IndexPage: HTMLDocument, Sendable {
+struct IndexPage {
 
     // MARK: Properties
 
     /// The locale the page content is localized to.
-    private let locale: Locale
+    let locale: Locale
 
     /// Resolves the page's text from the bundled String Catalog for the page's ``locale``.
     private let localize: Localize
@@ -24,77 +24,28 @@ struct IndexPage: HTMLDocument, Sendable {
         self.localize = .init(bundle: .module)
     }
 
-    // MARK: Document
+}
 
-    /// The page's content: a localized greeting followed by the shared and index scripts.
-    var body: some HTML {
+// MARK: - Page
+
+extension IndexPage: Page {
+
+    // MARK: Properties
+
+    var content: some HTML {
         p {
             localize("index.greeting", locale: locale)
         }
-        script(.src(StaticFile.index.urlPath(for: .js))) {}
-        script(.src(StaticFile.shared.urlPath(for: .js))) {}
     }
 
-    /// The metadata, stylesheet, icon, and manifest links placed in the document head.
-    var head: some HTML {
-        meta(.charset(.utf8))
-        meta(
-            .name(.viewport),
-            .content("width=device-width, initial-scale=1")
-        )
-        link(
-            .rel(.stylesheet),
-            .href(StaticFile.shared.urlPath(for: .css))
-        )
-        link(
-            .rel(.stylesheet),
-            .href(StaticFile.index.urlPath(for: .css))
-        )
-        link(
-            .rel(.icon),
-            .href(StaticFile.favicon.urlPath(for: .ico)),
-            .custom(
-                name: "sizes",
-                value: "any"
-            )
-        )
-        link(
-            .rel(.icon),
-            .href(StaticFile.icon.urlPath(for: .svg)),
-            .custom(
-                name: "type",
-                value: "image/svg+xml"
-            )
-        )
-        link(
-            .rel("apple-touch-icon"),
-            .href(StaticFile.appleTouchIcon.urlPath(for: .png))
-        )
-        link(
-            .rel("manifest"),
-            .href(StaticFile.site.urlPath(for: .webmanifest))
-        )
-        meta(
-            .name("theme-color"),
-            .content("#0c0710"),
-            .custom(
-                name: "media",
-                value: "(prefers-color-scheme: dark)"
-            )
-        )
-        meta(
-            .name("theme-color"),
-            .content("#fafafa")
-        )
+    var scripts: [StaticFile] {
+        [.index, .shared]
     }
 
-    /// 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
+    var stylesheets: [StaticFile] {
+        [.shared, .index]
     }
 
-    /// The localized document title.
     var title: String {
         localize("index.title", locale: locale)
     }

Services/Website/Sources/Library/Internal/Protocols/Page.swift

@@ -0,0 +1,107 @@
+import Elementary
+import Foundation
+import Localization
+
+/// A page of the website: an HTML document with the shared scaffolding assembled around the page's content.
+///
+/// A conforming page supplies its locale, its localized title, the stylesheets and scripts it needs, and its content; the protocol assembles the rest of the
+/// document around them: the metadata, stylesheet, icon, and manifest links in the head, the content followed by the script tags in the body, and the
+/// document language derived from the locale.
+protocol Page: HTMLDocument, Sendable {
+
+    // MARK: Associated types
+
+    /// The type of the page's markup.
+    associatedtype Content: HTML
+
+    // MARK: Properties
+
+    /// The page's markup, rendered before the ``scripts``.
+    @HTMLBuilder
+    var content: Content { get }
+
+    /// The locale the page content is localized to.
+    var locale: Locale { get }
+
+    /// The scripts loaded at the end of the document body, in order.
+    var scripts: [StaticFile] { get }
+
+    /// The stylesheets linked in the document head, in order.
+    var stylesheets: [StaticFile] { get }
+
+}
+
+// MARK: - Implementations
+
+extension Page {
+
+    // MARK: Computed
+
+    /// The page ``content`` followed by its ``scripts``.
+    @HTMLBuilder
+    var body: some HTML {
+        content
+        for file in scripts {
+            script(.src(file.urlPath(for: .js))) {}
+        }
+    }
+
+    /// The metadata, ``stylesheets``, icon, and manifest links placed in the document head.
+    @HTMLBuilder
+    var head: some HTML {
+        meta(.charset(.utf8))
+        meta(
+            .name(.viewport),
+            .content("width=device-width, initial-scale=1")
+        )
+        for file in stylesheets {
+            link(
+                .rel(.stylesheet),
+                .href(file.urlPath(for: .css))
+            )
+        }
+        link(
+            .rel(.icon),
+            .href(StaticFile.favicon.urlPath(for: .ico)),
+            .custom(
+                name: "sizes",
+                value: "any"
+            )
+        )
+        link(
+            .rel(.icon),
+            .href(StaticFile.icon.urlPath(for: .svg)),
+            .custom(
+                name: "type",
+                value: "image/svg+xml"
+            )
+        )
+        link(
+            .rel("apple-touch-icon"),
+            .href(StaticFile.appleTouchIcon.urlPath(for: .png))
+        )
+        link(
+            .rel("manifest"),
+            .href(StaticFile.site.urlPath(for: .webmanifest))
+        )
+        meta(
+            .name("theme-color"),
+            .content("#fafafa")
+        )
+        meta(
+            .name("theme-color"),
+            .content("#0c0710"),
+            .custom(
+                name: "media",
+                value: "(prefers-color-scheme: dark)"
+            )
+        )
+    }
+
+    /// 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
+    }
+
+}

Services/Website/Sources/Library/Public/Controllers/RootController.swift

@@ -25,7 +25,9 @@ public struct RootController<Context: LocalizedRequestContext> {
 
     /// Creates a root controller.
     public init() {
-        self.responses = .init { IndexPage(locale: $0) }
+        self.responses = .init {
+            IndexPage(locale: $0)
+        }
     }
 
 }

Services/Website/Tests/App/AppTests.swift

@@ -2,7 +2,6 @@ import Configuration
 import Foundation
 import Hummingbird
 import HummingbirdTesting
-import Logging
 import NIOCore
 import Testing
 

Services/Website/Tests/Library/Cases/Internal/Enumerations/StaticFileTests.swift

@@ -1,4 +1,3 @@
-import Foundation
 import Testing
 
 @testable import WebsiteLibrary