opennextjs · conico974 · Apr 28, 2025 · Apr 28, 2025 · Apr 28, 2025 · Apr 28, 2025
diff --git a/.changeset/neat-hornets-call.md b/.changeset/neat-hornets-call.md
@@ -0,0 +1,5 @@
+---
+"@opennextjs/cloudflare": patch
+---
+
+Add a new `withFilter` tag cache to allow to filter the tags used
diff --git a/packages/cloudflare/src/api/overrides/tag-cache/tag-cache-filter.spec.ts b/packages/cloudflare/src/api/overrides/tag-cache/tag-cache-filter.spec.ts
@@ -0,0 +1,119 @@
+import { NextModeTagCache } from "@opennextjs/aws/types/overrides";
+import { beforeEach, describe, expect, it, vi } from "vitest";
+
+import { softTagFilter, withFilter } from "./tag-cache-filter";
+
+const mockedTagCache = {
+  name: "mocked",
+  mode: "nextMode",
+  getPathsByTags: vi.fn(),
+  hasBeenRevalidated: vi.fn(),
+  writeTags: vi.fn(),
+} satisfies NextModeTagCache;
+
+const filterFn = (tag: string) => tag.startsWith("valid_");
+
+describe("withFilter", () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+  });
+
+  it("should filter out tags based on writeTags", async () => {
+    const tagCache = withFilter({
+      tagCache: mockedTagCache,
+      filterFn,
+    });
+
+    const tags = ["valid_tag", "invalid_tag"];
+
+    await tagCache.writeTags(tags);
+    expect(mockedTagCache.writeTags).toHaveBeenCalledWith(["valid_tag"]);
+  });
+
+  it("should not call writeTags if no tags are valid", async () => {
+    const tagCache = withFilter({
+      tagCache: mockedTagCache,
+      filterFn,
+    });
+    const tags = ["invalid_tag"];
+    await tagCache.writeTags(tags);
+    expect(mockedTagCache.writeTags).not.toHaveBeenCalled();
+  });
+
+  it("should filter out tags based on hasBeenRevalidated", async () => {
+    const tagCache = withFilter({
+      tagCache: mockedTagCache,
+      filterFn,
+    });
+
+    const tags = ["valid_tag", "invalid_tag"];
+    const lastModified = Date.now();
+
+    await tagCache.hasBeenRevalidated(tags, lastModified);
+    expect(mockedTagCache.hasBeenRevalidated).toHaveBeenCalledWith(["valid_tag"], lastModified);
+  });
+
+  it("should not call hasBeenRevalidated if no tags are valid", async () => {
+    const tagCache = withFilter({
+      tagCache: mockedTagCache,
+      filterFn,
+    });
+    const tags = ["invalid_tag"];
+    const lastModified = Date.now();
+    await tagCache.hasBeenRevalidated(tags, lastModified);
+    expect(mockedTagCache.hasBeenRevalidated).not.toHaveBeenCalled();
+  });
+
+  it("should filter out tags based on getPathsByTags", async () => {
+    const tagCache = withFilter({
+      tagCache: mockedTagCache,
+      filterFn,
+    });
+
+    const tags = ["valid_tag", "invalid_tag"];
+
+    await tagCache.getPathsByTags?.(tags);
+    expect(mockedTagCache.getPathsByTags).toHaveBeenCalledWith(["valid_tag"]);
+  });
+
+  it("should not call getPathsByTags if no tags are valid", async () => {
+    const tagCache = withFilter({
+      tagCache: mockedTagCache,
+      filterFn,
+    });
+    const tags = ["invalid_tag"];
+    await tagCache.getPathsByTags?.(tags);
+    expect(mockedTagCache.getPathsByTags).not.toHaveBeenCalled();
+  });
+
+  it("should return the correct name", () => {
+    const tagCache = withFilter({
+      tagCache: mockedTagCache,
+      filterFn,
+    });
+
+    expect(tagCache.name).toBe("filtered-mocked");
+  });
+
+  it("should not create a function if getPathsByTags is not defined", async () => {
+    const tagCache = withFilter({
+      tagCache: {
+        ...mockedTagCache,
+        getPathsByTags: undefined,
+      },
+      filterFn,
+    });
+
+    expect(tagCache.getPathsByTags).toBeUndefined();
+  });
+
+  it("should filter soft tags", () => {
+    const tagCache = withFilter({
+      tagCache: mockedTagCache,
+      filterFn: softTagFilter,
+    });
+
+    tagCache.writeTags(["valid_tag", "_N_T_/", "_N_T_/test", "_N_T_/layout"]);
+    expect(mockedTagCache.writeTags).toHaveBeenCalledWith(["valid_tag"]);
+  });
+});
diff --git a/packages/cloudflare/src/api/overrides/tag-cache/tag-cache-filter.ts b/packages/cloudflare/src/api/overrides/tag-cache/tag-cache-filter.ts
@@ -0,0 +1,58 @@
+import { NextModeTagCache } from "@opennextjs/aws/types/overrides";
+
+interface WithFilterOptions {
+  /**
+   * The original tag cache.
+   * Call to this will receive only the filtered tags.
+   */
+  tagCache: NextModeTagCache;
+  /**
+   * The function to filter tags.
+   * @param tag The tag to filter.
+   * @returns true if the tag should be forwarded, false otherwise.
+   */
+  filterFn: (tag: string) => boolean;
+}
+
+/**
+ * Creates a new tag cache that filters tags based on the provided filter function.
+ * This is useful to remove tags that are not used by the app, this could reduce the number of requests to the underlying tag cache.
+ */
+export function withFilter({ tagCache, filterFn }: WithFilterOptions): NextModeTagCache {
+  return {
+    name: `filtered-${tagCache.name}`,
+    mode: "nextMode",
+    getPathsByTags: tagCache.getPathsByTags
+      ? async (tags) => {
+          const filteredTags = tags.filter(filterFn);
+          if (filteredTags.length === 0) {
+            return [];
+          }
+          return tagCache.getPathsByTags!(filteredTags);
+        }
+      : undefined,
+    hasBeenRevalidated: async (tags, lastModified) => {
+      const filteredTags = tags.filter(filterFn);
+      if (filteredTags.length === 0) {
+        return false;
+      }
+      return tagCache.hasBeenRevalidated(filteredTags, lastModified);
+    },
+    writeTags: async (tags) => {
+      const filteredTags = tags.filter(filterFn);
+      if (filteredTags.length === 0) {
+        return;
+      }
+      return tagCache.writeTags(filteredTags);
+    },
+  };
+}
+
+/**
+ * Filter function to exclude tags that start with "_N_T_".
+ * This is used to filter out internal soft tags.
+ * Can be used if `revalidatePath` is not used.
+ */
+export function softTagFilter(tag: string): boolean {
+  return !tag.startsWith("_N_T_");
+}