@fortedigital/nextjs-cache-handler/dist/functions/functions.js

Next.js cache handlers

// src/functions/nesh-classic-cache.ts
import assert from "assert/strict";
import { createHash } from "crypto";
import { workAsyncStorage } from "next/dist/server/app-render/work-async-storage.external.js";
import { CACHE_ONE_YEAR } from "next/dist/lib/constants";
function hashCacheKey(url) {
  const MAIN_KEY_PREFIX = "nesh-pages-cache-v1";
  const cacheString = JSON.stringify([MAIN_KEY_PREFIX, url]);
  return createHash("sha256").update(cacheString).digest("hex");
}
function serializeArguments(object) {
  return JSON.stringify(object);
}
function serializeResult(object) {
  return Buffer.from(JSON.stringify(object), "utf-8").toString("base64");
}
function deserializeResult(string) {
  return JSON.parse(Buffer.from(string, "base64").toString("utf-8"));
}
function neshClassicCache(callback, commonOptions) {
  if (commonOptions?.resultSerializer && !commonOptions?.resultDeserializer) {
    throw new Error(
      "neshClassicCache: if you provide a resultSerializer, you must provide a resultDeserializer."
    );
  }
  if (commonOptions?.resultDeserializer && !commonOptions?.resultSerializer) {
    throw new Error(
      "neshClassicCache: if you provide a resultDeserializer, you must provide a resultSerializer."
    );
  }
  const commonRevalidate = commonOptions?.revalidate ?? false;
  const commonArgumentsSerializer = commonOptions?.argumentsSerializer ?? serializeArguments;
  const commonResultSerializer = commonOptions?.resultSerializer ?? serializeResult;
  const commonResultDeserializer = commonOptions?.resultDeserializer ?? deserializeResult;
  async function cachedCallback(options, ...args) {
    const store = workAsyncStorage.getStore();
    assert(
      !store?.incrementalCache,
      "neshClassicCache must be used in a Next.js Pages directory."
    );
    const cacheHandler = globalThis?.__incrementalCache?.cacheHandler;
    assert(
      cacheHandler,
      "neshClassicCache must be used in a Next.js Pages directory."
    );
    const {
      responseContext,
      tags = [],
      revalidate = commonRevalidate,
      cacheKey,
      argumentsSerializer = commonArgumentsSerializer,
      resultDeserializer = commonResultDeserializer,
      resultSerializer = commonResultSerializer
    } = options ?? {};
    assert(
      revalidate === false || revalidate > 0 && Number.isInteger(revalidate),
      "neshClassicCache: revalidate must be a positive integer or false."
    );
    responseContext?.setHeader(
      "Cache-Control",
      `public, s-maxage=${revalidate}, stale-while-revalidate`
    );
    const uniqueTags = /* @__PURE__ */ new Set();
    for (const tag of tags) {
      if (typeof tag === "string") {
        uniqueTags.add(tag);
      } else {
        console.warn(
          `neshClassicCache: Invalid tag: ${tag}. Skipping it. Expected a string.`
        );
      }
    }
    const allTags = Array.from(uniqueTags);
    const key = hashCacheKey(
      `nesh-classic-cache-${cacheKey ?? argumentsSerializer(args)}`
    );
    const cacheData = await cacheHandler.get(key, {
      revalidate,
      tags: allTags,
      kind: "FETCH",
      fetchUrl: "neshClassicCache"
    });
    if (cacheData?.value?.kind === "FETCH" && cacheData.lifespan && cacheData.lifespan.staleAt > Date.now() / 1e3) {
      return resultDeserializer(cacheData.value.data.body);
    }
    const data = await callback(...args);
    cacheHandler.set(
      key,
      {
        kind: "FETCH",
        data: {
          body: resultSerializer(data),
          headers: {},
          url: "neshClassicCache"
        },
        revalidate: revalidate || CACHE_ONE_YEAR
      },
      {
        revalidate,
        tags,
        fetchCache: true,
        fetchUrl: "neshClassicCache"
      }
    );
    if (cacheData?.value?.kind === "FETCH" && cacheData?.lifespan && cacheData.lifespan.expireAt > Date.now() / 1e3) {
      return resultDeserializer(cacheData.value.data.body);
    }
    return data;
  }
  return cachedCallback;
}
export {
  neshClassicCache
};