feat: support pagination (#17)

* pagination

* tests

* Add rare-lemons-share.md

* Update rare-lemons-share.md

Author: morinokami

.changeset/rare-lemons-share.md

@@ -0,0 +1,5 @@
+---
+"tanstack-meta": minor
+---
+
+feat: support pagination

packages/meta/README.md

@@ -78,6 +78,7 @@ An object containing `meta` and `links` properties, which can be used as the ret
 - `archives`
 - `assets`
 - `bookmarks`
+- `pagination`
 - `category`
 - `classification`
 - `other`

packages/meta/src/generate/basic.test.ts

@@ -184,6 +184,33 @@ describe("generateBasicLinks", () => {
 			{ rel: "bookmarks", href: "https://example.com/bookmark2" },
 		]);
 	});
+
+	test("emits pagination links when previous and next are provided", () => {
+		const metadata = normalizeMetadata({
+			pagination: {
+				previous: "https://example.com/page/1",
+				next: "https://example.com/page/3",
+			},
+		});
+
+		expect(generateBasicLinks(metadata)).toEqual([
+			{ rel: "previous", href: "https://example.com/page/1" },
+			{ rel: "next", href: "https://example.com/page/3" },
+		]);
+	});
+
+	test("omits missing pagination entries and stringifies URLs", () => {
+		const metadata = normalizeMetadata({
+			pagination: {
+				previous: new URL("https://example.com/page/2"),
+				next: null,
+			},
+		});
+
+		expect(generateBasicLinks(metadata)).toEqual([
+			{ rel: "previous", href: "https://example.com/page/2" },
+		]);
+	});
 });
 
 describe("generateItunes", () => {

packages/meta/src/generate/basic.ts

@@ -70,6 +70,16 @@ export function generateBasicLinks(metadata: NormalizedMetadata): OutputLinks {
 					href: bookmark,
 				}))
 			: []),
+		...(metadata.pagination
+			? [
+					metadata.pagination.previous
+						? { rel: "previous", href: metadata.pagination.previous }
+						: null,
+					metadata.pagination.next
+						? { rel: "next", href: metadata.pagination.next }
+						: null,
+				]
+			: []),
 	]);
 }
 

packages/meta/src/normalize/basic.test.ts

@@ -5,6 +5,7 @@ import {
 	normalizeAppleWebApp,
 	normalizeFacebook,
 	normalizeItunes,
+	normalizePagination,
 	normalizeRobotsValue,
 	normalizeVerification,
 } from "./basic";
@@ -141,6 +142,26 @@ describe("normalizeItunes", () => {
 	});
 });
 
+describe("normalizePagination", () => {
+	test("returns null values when input is falsy", () => {
+		const result = normalizePagination(undefined);
+
+		expect(result).toEqual({ previous: null, next: null });
+	});
+
+	test("converts URL instances to strings and preserves provided values", () => {
+		const result = normalizePagination({
+			previous: new URL("https://example.com/page/1"),
+			next: "https://example.com/page/3",
+		});
+
+		expect(result).toEqual({
+			previous: "https://example.com/page/1",
+			next: "https://example.com/page/3",
+		});
+	});
+});
+
 describe("normalizeRobotsValue", () => {
 	test("returns null when input is falsy", () => {
 		const result = normalizeRobotsValue(undefined);

packages/meta/src/normalize/basic.ts

@@ -169,3 +169,15 @@ export const normalizeFacebook = (facebook: InputMetadata["facebook"]) => {
 		admins: resolveAsArrayOrUndefined(facebook.admins),
 	};
 };
+
+function resolveUrl(url: string | URL): string {
+	return url instanceof URL ? url.toString() : url;
+}
+export const normalizePagination = (
+	pagination: InputMetadata["pagination"],
+) => {
+	return {
+		previous: pagination?.previous ? resolveUrl(pagination.previous) : null,
+		next: pagination?.next ? resolveUrl(pagination.next) : null,
+	};
+};

packages/meta/src/normalize/index.ts

@@ -5,6 +5,7 @@ import {
 	normalizeAppleWebApp,
 	normalizeFacebook,
 	normalizeItunes,
+	normalizePagination,
 	normalizeRobotsValue,
 	normalizeVerification,
 } from "./basic";
@@ -45,6 +46,7 @@ export function normalizeMetadata(metadata: InputMetadata): NormalizedMetadata {
 		archives: resolveAsArrayOrUndefined(metadata.archives) ?? null,
 		assets: resolveAsArrayOrUndefined(metadata.assets) ?? null,
 		bookmarks: resolveAsArrayOrUndefined(metadata.bookmarks) ?? null,
+		pagination: normalizePagination(metadata.pagination),
 		category: metadata.category ?? null,
 		classification: metadata.classification ?? null,
 		other: metadata.other ?? null,

packages/meta/src/types/io.ts

@@ -193,6 +193,24 @@ export type InputMetadata = {
 	 * ```
 	 */
 	bookmarks?: NextMetadata["bookmarks"];
+	/**
+	 * The pagination link rel properties.
+	 *
+	 * @example
+	 * ```tsx
+	 * pagination: {
+	 *   previous: "https://example.com/items?page=1",
+	 *   next: "https://example.com/items?page=3"
+	 * }
+	 *
+	 * // Renders
+	 * <link rel="prev" href="https://example.com/items?page=1" />
+	 * <link rel="next" href="https://example.com/items?page=3" />
+	 * ```
+	 *
+	 * @see https://developers.google.com/search/blog/2011/09/pagination-with-relnext-and-relprev
+	 */
+	pagination?: NextMetadata["pagination"];
 	/**
 	 * The category meta name property.
 	 *
@@ -465,6 +483,7 @@ export type NormalizedMetadata = {
 	archives: ResolvedMetadata["archives"];
 	assets: ResolvedMetadata["assets"];
 	bookmarks: ResolvedMetadata["bookmarks"];
+	pagination: ResolvedMetadata["pagination"];
 	category: ResolvedMetadata["category"];
 	classification: ResolvedMetadata["classification"];
 	other: ResolvedMetadata["other"];