Social Card tweaks in the Infrastructure package. (#30)

This PR contains the work done to address certain tweaks in the newly-introduced _Social Card_ types in the **Infrastructure** package.

Reviewed-on: rock-n-code/loud-amsterdam#30
Co-authored-by: Javier Cicchelli <javier@rock-n-code.com>

Packages/Infrastructure/README.md

@@ -8,7 +8,7 @@ The package provides, grouped by role:
 | Routing | `RouterController`, `RouteCollectionBuilder`, the `addController` extension on `RouterMethods` |
 | Middlewares | `SecurityHeadersMiddleware`, `VaryMiddleware`, `RateLimitMiddleware`, `LocalizationMiddleware`, `NotFoundMiddleware` |
 | Pages and assets | `Page`, `Asset`, `AssetExtension`, `FingerprintAssets` |
-| Link previews | `SocialCard`, its `Image`, and the `SocialCardTag` meta tags it derives |
+| Link previews | `SocialCard`, its `Image`, and the `Tag` meta tags it derives |
 | Responses | `CachedHTMLResponse`, `LocalizedHTMLCollectionResponse` |
 | Contexts | `LocalizedRequestContext` |
 | Constants | The `HTTPField.Name` header names, `Int.RateLimit` limits, and `String.Security` header values the middlewares default to |

Packages/Infrastructure/Sources/Public/Types/SocialCard.swift

@@ -70,52 +70,16 @@ public struct SocialCard: Sendable {
 
     /// The card's meta tags, in a stable order: the Open Graph type, site name, title, description, URL, and locale, then the image group, and
     /// the Twitter card style last. A tag whose fact the card does not carry is left out.
-    public var tags: [SocialCardTag] {
-        let tags: [SocialCardTag?] = [
-            SocialCardTag(
-                attribute: .property,
-                content: type,
-                name: .type
-            ),
-            siteName.map {
-                SocialCardTag(
-                    attribute: .property,
-                    content: $0,
-                    name: .siteName
-                )
-            },
-            SocialCardTag(
-                attribute: .property,
-                content: title,
-                name: .title
-            ),
-            summary.map {
-                SocialCardTag(
-                    attribute: .property,
-                    content: $0,
-                    name: .description
-                )
-            },
-            url.map {
-                SocialCardTag(
-                    attribute: .property,
-                    content: $0,
-                    name: .url
-                )
-            },
-            locale.map {
-                SocialCardTag(
-                    attribute: .property,
-                    content: $0,
-                    name: .locale
-                )
-            },
+    public var tags: [Tag] {
+        let tags: [Tag?] = [
+            Tag(type, name: .type),
+            siteName.map { Tag($0, name: .siteName) },
+            Tag(title, name: .title),
+            summary.map { Tag($0, name: .description) },
+            url.map { Tag($0, name: .url) },
+            locale.map { Tag($0, name: .locale) },
         ] + (image?.tags ?? []) + [
-            SocialCardTag(
-                attribute: .name,
-                content: style.rawValue,
-                name: .twitter
-            ),
+            Tag(style.rawValue, name: .twitter),
         ]
 
         return tags.compactMap { $0 }

Packages/Infrastructure/Sources/Public/Types/SocialCard/SocialCardImage.swift

@@ -39,30 +39,12 @@ extension SocialCard {
         // MARK: Computed
         
         /// The image's meta tags, in a stable order: its URL, width, and height, then its alt text when it carries one.
-        public var tags: [SocialCardTag] {
-            let tags: [SocialCardTag?] = [
-                SocialCardTag(
-                    attribute: .property,
-                    content: url,
-                    name: .image
-                ),
-                SocialCardTag(
-                    attribute: .property,
-                    content: String(width),
-                    name: .imageWidth
-                ),
-                SocialCardTag(
-                    attribute: .property,
-                    content: String(height),
-                    name: .imageHeight
-                ),
-                alt.map {
-                    SocialCardTag(
-                        attribute: .property,
-                        content: $0,
-                        name: .imageAlt
-                    )
-                },
+        public var tags: [Tag] {
+            let tags: [Tag?] = [
+                Tag(url, name: .image),
+                Tag(String(width), name: .imageWidth),
+                Tag(String(height), name: .imageHeight),
+                alt.map { Tag($0, name: .imageAlt) },
             ]
 
             return tags.compactMap { $0 }

Packages/Infrastructure/Sources/Public/Types/SocialCard/SocialCardTag.swift

@@ -1,24 +1,44 @@
-/// A head meta tag of a ``SocialCard``: which attribute keys it, and its name and content.
-public struct SocialCardTag: Equatable, Sendable {
+extension SocialCard {
+    /// A head meta tag of a ``SocialCard``: its name and content, keyed by the attribute its ``name`` dictates.
+    public struct Tag: Equatable, Sendable {
 
-    // MARK: Properties
+        // MARK: Properties
 
-    /// The attribute the tag is keyed by.
-    public let attribute: Attribute
+        /// The tag's value.
+        public let content: String
 
-    /// The tag's value.
-    public let content: String
+        /// The tag's name.
+        public let name: Name
+        
+        // MARK: Initializers
 
-    /// The tag's name.
-    public let name: Name
+        /// Creates a head meta tag.
+        /// - Parameters:
+        ///   - content: the tag's value.
+        ///   - name: the tag's name, dictating the attribute the tag is keyed by.
+        public init(
+            _ content: String,
+            name: Name
+        ) {
+            self.content = content
+            self.name = name
+        }
 
+        // MARK: Computed
+
+        /// The attribute the tag is keyed by, dictated by its ``name``.
+        public var attribute: Attribute {
+            name.attribute
+        }
+
+    }
 }
 
 // MARK: - Enumerations
 
-extension SocialCardTag {
-    
-    /// The meta attribute a ``SocialCardTag`` is keyed by, named by its raw value.
+extension SocialCard.Tag {
+
+    /// The meta attribute a ``SocialCard/Tag`` is keyed by, named by its raw value.
     public enum Attribute: String, Sendable {
         /// The `name` attribute, keying the Twitter tags.
         case name
@@ -26,7 +46,7 @@ extension SocialCardTag {
         case property
     }
 
-    /// The name of a ``SocialCardTag``, carried in its raw value.
+    /// The name of a ``SocialCard/Tag``, carried in its raw value.
     public enum Name: String, Sendable {
         /// The `og:description` tag, carrying the card's summary.
         case description = "og:description"
@@ -34,10 +54,10 @@ extension SocialCardTag {
         case image = "og:image"
         /// The `og:image:alt` tag, carrying the share image's text for assistive technologies.
         case imageAlt = "og:image:alt"
-        /// The `og:image:width` tag, carrying the share image's width in pixels.
-        case imageWidth = "og:image:width"
         /// The `og:image:height` tag, carrying the share image's height in pixels.
         case imageHeight = "og:image:height"
+        /// The `og:image:width` tag, carrying the share image's width in pixels.
+        case imageWidth = "og:image:width"
         /// The `og:locale` tag, carrying the locale of the card's text.
         case locale = "og:locale"
         /// The `og:site_name` tag, carrying the name of the site the card belongs to.
@@ -51,5 +71,18 @@ extension SocialCardTag {
         /// The `og:url` tag, carrying the absolute URL the card's page is served at.
         case url = "og:url"
     }
-    
+
+}
+
+// MARK: - Implementations
+
+public extension SocialCard.Tag.Name {
+
+    // MARK: Computed
+
+    /// The attribute keying a tag with this name: `property` for the Open Graph names, `name` for the Twitter ones.
+    var attribute: SocialCard.Tag.Attribute {
+        self == .twitter ? .name : .property
+    }
+
 }

Packages/Infrastructure/Tests/Cases/Public/Types/SocialCardTests.swift

@@ -27,17 +27,17 @@ struct SocialCardTests {
         )
 
         #expect(card.tags == [
-            .init(attribute: .property, content: "website", name: .type),
-            .init(attribute: .property, content: "A Site", name: .siteName),
-            .init(attribute: .property, content: "A Title", name: .title),
-            .init(attribute: .property, content: "A summary.", name: .description),
-            .init(attribute: .property, content: "https://site.example/", name: .url),
-            .init(attribute: .property, content: "en", name: .locale),
-            .init(attribute: .property, content: "https://site.example/img/card.png", name: .image),
-            .init(attribute: .property, content: "2400", name: .imageWidth),
-            .init(attribute: .property, content: "1260", name: .imageHeight),
-            .init(attribute: .property, content: "An image.", name: .imageAlt),
-            .init(attribute: .name, content: "summary_large_image", name: .twitter),
+            .init("website", name: .type),
+            .init("A Site", name: .siteName),
+            .init("A Title", name: .title),
+            .init("A summary.", name: .description),
+            .init("https://site.example/", name: .url),
+            .init("en", name: .locale),
+            .init("https://site.example/img/card.png", name: .image),
+            .init("2400", name: .imageWidth),
+            .init("1260", name: .imageHeight),
+            .init("An image.", name: .imageAlt),
+            .init("summary_large_image", name: .twitter),
         ])
     }
 
@@ -46,9 +46,9 @@ struct SocialCardTests {
         let card = SocialCard(title: "A Title")
 
         #expect(card.tags == [
-            .init(attribute: .property, content: "website", name: .type),
-            .init(attribute: .property, content: "A Title", name: .title),
-            .init(attribute: .name, content: "summary_large_image", name: .twitter),
+            .init("website", name: .type),
+            .init("A Title", name: .title),
+            .init("summary_large_image", name: .twitter),
         ])
     }
 
@@ -77,8 +77,15 @@ struct SocialCardTests {
             style: .summary
         )
 
-        #expect(card.tags.contains(.init(attribute: .property, content: "article", name: .type)))
-        #expect(card.tags.contains(.init(attribute: .name, content: "summary", name: .twitter)))
+        #expect(card.tags.contains(.init("article", name: .type)))
+        #expect(card.tags.contains(.init("summary", name: .twitter)))
+    }
+
+    @Test
+    func `keys a tag by the attribute its name dictates`() {
+        #expect(SocialCard.Tag.Name.twitter.attribute == .name)
+        #expect(SocialCard.Tag.Name.title.attribute == .property)
+        #expect(SocialCard.Tag("website", name: .type).attribute == .property)
     }
 
 }