ビルド時の Notion API 負荷を削減

package.json

@@ -4,7 +4,7 @@
   "private": true,
   "scripts": {
     "dev": "next dev",
-    "build": "next build",
+    "build": "node scripts/clear-notion-build-cache.mjs && next build",
     "start": "next start",
     "lint": "next lint",
     "storybook": "storybook dev -p 6006",

scripts/clear-notion-build-cache.mjs

@@ -0,0 +1,6 @@
+import fs from "fs/promises";
+import path from "path";
+
+const cacheDir = path.join(process.cwd(), ".next/cache/notion-build");
+
+await fs.rm(cacheDir, { recursive: true, force: true });

src/utils/notion.ts

@@ -1,19 +1,186 @@
+import crypto from "crypto";
+import fs from "fs/promises";
+import path from "path";
 import { Client } from "@notionhq/client";
 
 const notionClient = new Client({
   auth: process.env.NOTION_TOKEN,
 });
 
-export const getDatabase = async (databaseId: string) => {
+const NOTION_REQUEST_INTERVAL_MS = 350;
+const MAX_RETRY_COUNT = 5;
+const BUILD_CACHE_DIR = path.join(process.cwd(), ".next/cache/notion-build");
+const RATE_LIMIT_DIR = path.join(
+  process.cwd(),
+  ".next/cache/notion-rate-limit",
+);
+const RATE_LIMIT_LOCK_DIR = `${RATE_LIMIT_DIR}.lock`;
+const RATE_LIMIT_STATE_FILE = path.join(RATE_LIMIT_DIR, "state.json");
+const databaseCache = new Map<string, Promise<any[]>>();
+
+let lastLocalRequestStartedAt = 0;
+let requestQueue = Promise.resolve();
+
+const wait = (ms: number) => new Promise((resolve) => setTimeout(resolve, ms));
+
+const isProductionBuild = () =>
+  process.env.NODE_ENV === "production" &&
+  process.env.npm_lifecycle_event === "build";
+
+const shouldUseBuildCache = () => isProductionBuild();
+
+const getRequiredDatabaseId = (databaseId: string | undefined) => {
+  if (!databaseId) {
+    throw new Error("Notion database id is not set.");
+  }
+  return databaseId;
+};
+
+const getDatabaseCacheFile = (databaseId: string) => {
+  const cacheKey = crypto.createHash("sha256").update(databaseId).digest("hex");
+  return path.join(BUILD_CACHE_DIR, `${cacheKey}.json`);
+};
+
+const readJsonIfExists = async <T>(filePath: string): Promise<T | null> => {
+  try {
+    const json = await fs.readFile(filePath, "utf8");
+    return JSON.parse(json) as T;
+  } catch (error: any) {
+    if (error?.code === "ENOENT") return null;
+    throw error;
+  }
+};
+
+const getRetryAfterMs = (error: any) => {
+  const retryAfter =
+    error?.headers?.get?.("retry-after") ??
+    error?.headers?.get?.("Retry-After") ??
+    error?.headers?.["retry-after"] ??
+    error?.headers?.["Retry-After"];
+
+  const retryAfterSeconds = Number(retryAfter);
+  if (Number.isFinite(retryAfterSeconds) && retryAfterSeconds > 0) {
+    return retryAfterSeconds * 1000;
+  }
+
+  return null;
+};
+
+const isRateLimited = (error: any) =>
+  error?.code === "rate_limited" || error?.status === 429;
+
+const acquireFileLock = async (lockDir: string, timeoutMs: number) => {
+  await fs.mkdir(path.dirname(lockDir), { recursive: true });
+
+  const startedAt = Date.now();
+  while (true) {
+    try {
+      await fs.mkdir(lockDir);
+      return;
+    } catch (error: any) {
+      if (error?.code !== "EEXIST") throw error;
+
+      if (Date.now() - startedAt > timeoutMs) {
+        await fs.rm(lockDir, { recursive: true, force: true });
+        continue;
+      }
+
+      await wait(50);
+    }
+  }
+};
+
+const waitForSharedRateLimitSlot = async () => {
+  await acquireFileLock(RATE_LIMIT_LOCK_DIR, 30 * 1000);
+
+  let waitMs = 0;
+  try {
+    await fs.mkdir(RATE_LIMIT_DIR, { recursive: true });
+    const state = await readJsonIfExists<{ nextRequestAt: number }>(
+      RATE_LIMIT_STATE_FILE,
+    );
+    const now = Date.now();
+    const nextRequestAt = Math.max(now, state?.nextRequestAt ?? 0);
+    waitMs = Math.max(0, nextRequestAt - now);
+
+    const tempFile = `${RATE_LIMIT_STATE_FILE}.${process.pid}.tmp`;
+    await fs.writeFile(
+      tempFile,
+      JSON.stringify({
+        nextRequestAt: nextRequestAt + NOTION_REQUEST_INTERVAL_MS,
+      }),
+      "utf8",
+    );
+    await fs.rename(tempFile, RATE_LIMIT_STATE_FILE);
+  } finally {
+    await fs.rm(RATE_LIMIT_LOCK_DIR, { recursive: true, force: true });
+  }
+
+  if (waitMs > 0) {
+    await wait(waitMs);
+  }
+};
+
+const waitForLocalRateLimitSlot = async () => {
+  const elapsed = Date.now() - lastLocalRequestStartedAt;
+  if (elapsed < NOTION_REQUEST_INTERVAL_MS) {
+    await wait(NOTION_REQUEST_INTERVAL_MS - elapsed);
+  }
+
+  lastLocalRequestStartedAt = Date.now();
+};
+
+const waitForRateLimitSlot = async () => {
+  if (isProductionBuild()) {
+    await waitForSharedRateLimitSlot();
+    return;
+  }
+
+  await waitForLocalRateLimitSlot();
+};
+
+const runWithRetry = async <T>(request: () => Promise<T>): Promise<T> => {
+  let attempt = 0;
+
+  while (true) {
+    try {
+      await waitForRateLimitSlot();
+      return await request();
+    } catch (error) {
+      if (!isRateLimited(error) || attempt >= MAX_RETRY_COUNT) {
+        throw error;
+      }
+
+      const retryAfterMs = getRetryAfterMs(error) ?? 1000 * 2 ** attempt;
+      await wait(retryAfterMs);
+      attempt += 1;
+    }
+  }
+};
+
+const runNotionRequest = async <T>(request: () => Promise<T>) => {
+  const queuedRequest = requestQueue.then(() => runWithRetry(request));
+
+  requestQueue = queuedRequest.then(
+    () => undefined,
+    () => undefined,
+  );
+
+  return queuedRequest;
+};
+
+const fetchDatabase = async (databaseId: string) => {
   let results: any[] = [];
   let cursor: string | undefined = undefined;
 
   do {
-    const response = await notionClient.databases.query({
-      database_id: databaseId,
-      page_size: 100,
-      start_cursor: cursor,
-    });
+    const response = await runNotionRequest(() =>
+      notionClient.databases.query({
+        database_id: databaseId,
+        page_size: 100,
+        start_cursor: cursor,
+      }),
+    );
 
     results.push(...response.results);
     cursor = response.has_more ? response.next_cursor ?? undefined : undefined;
@@ -22,22 +189,85 @@ export const getDatabase = async (databaseId: string) => {
   return results;
 };
 
+const getDatabaseWithBuildCache = async (databaseId: string) => {
+  const cacheFile = getDatabaseCacheFile(databaseId);
+  const lockDir = `${cacheFile}.lock`;
+  const existingCache = await readJsonIfExists<any[]>(cacheFile);
+  if (existingCache) return existingCache;
+
+  await fs.mkdir(BUILD_CACHE_DIR, { recursive: true });
+  await acquireFileLock(lockDir, 10 * 60 * 1000);
+
+  try {
+    const cache = await readJsonIfExists<any[]>(cacheFile);
+    if (cache) return cache;
+
+    const results = await fetchDatabase(databaseId);
+    const tempFile = `${cacheFile}.${process.pid}.tmp`;
+    await fs.writeFile(tempFile, JSON.stringify(results), "utf8");
+    await fs.rename(tempFile, cacheFile);
+    return results;
+  } finally {
+    await fs.rm(lockDir, { recursive: true, force: true });
+  }
+};
+
+export const getDatabase = async (databaseId: string | undefined) => {
+  const requiredDatabaseId = getRequiredDatabaseId(databaseId);
+
+  if (!shouldUseBuildCache()) {
+    return fetchDatabase(requiredDatabaseId);
+  }
+
+  const cachedPromise = databaseCache.get(requiredDatabaseId);
+  if (cachedPromise) return cachedPromise;
+
+  const databasePromise = getDatabaseWithBuildCache(requiredDatabaseId);
+  databaseCache.set(requiredDatabaseId, databasePromise);
+
+  try {
+    return await databasePromise;
+  } catch (error) {
+    databaseCache.delete(requiredDatabaseId);
+    throw error;
+  }
+};
+
 export const getPage = async (pageId: string) => {
-  const response = await notionClient.pages.retrieve({
-    page_id: pageId,
-  });
+  const response = await runNotionRequest(() =>
+    notionClient.pages.retrieve({
+      page_id: pageId,
+    }),
+  );
 
   return response;
 };
 
+const listBlockChildren = async (blockId: string) => {
+  let results: any[] = [];
+  let cursor: string | undefined = undefined;
+
+  do {
+    const response = await runNotionRequest(() =>
+      notionClient.blocks.children.list({
+        block_id: blockId,
+        page_size: 100,
+        start_cursor: cursor,
+      }),
+    );
+
+    results.push(...response.results);
+    cursor = response.has_more ? response.next_cursor ?? undefined : undefined;
+  } while (cursor);
+
+  return results;
+};
+
 // TODO: add types
 export const getBlocks = async (blockId: string) => {
   blockId = blockId.replaceAll("-", "");
 
-  const { results } = await notionClient.blocks.children.list({
-    block_id: blockId,
-    page_size: 100,
-  });
+  const results = await listBlockChildren(blockId);
 
   // get nested blocks
   const childBlocks: any = results.map(async (block: any) => {