Lokalise Performance Tuning

Instructions

Step 1: Enable Compression

const client = new LokaliseApi({
  apiKey: process.env.LOKALISE_API_TOKEN!,
  enableCompression: true,  // Enable gzip for large responses
});

Step 2: Implement Response Caching

import { LRUCache } from "lru-cache";

const cache = new LRUCache<string, any>({
  max: 1000,
  ttl: 60000,  // 1 minute default TTL
  updateAgeOnGet: true,
});

async function cachedRequest<T>(
  key: string,
  fetcher: () => Promise<T>,
  ttl?: number
): Promise<T> {
  const cached = cache.get(key);
  if (cached !== undefined) {
    return cached as T;
  }

  const result = await fetcher();
  cache.set(key, result, { ttl });
  return result;
}

// Usage
async function getProject(projectId: string) {
  return cachedRequest(
    `project:${projectId}`,
    () => client.projects().get(projectId),
    300000  // 5 minutes
  );
}

async function getKeys(projectId: string) {
  return cachedRequest(
    `keys:${projectId}`,
    () => client.keys().list({ project_id: projectId, limit: 500 }),
    60000  // 1 minute
  );
}

Step 3: Use Cursor Pagination

// Cursor pagination is more efficient for large datasets
async function* iterateAllKeys(projectId: string) {
  let cursor: string | undefined;

  do {
    const result = await client.keys().list({
      project_id: projectId,
      limit: 500,  // Max allowed
      pagination: "cursor",
      cursor,
    });

    for (const key of result.items) {
      yield key;
    }

    cursor = result.hasNextCursor() ? result.nextCursor : undefined;
  } while (cursor);
}

// Usage
async function getAllKeys(projectId: string) {
  const keys = [];
  for await (const key of iterateAllKeys(projectId)) {
    keys.push(key);
  }
  return keys;
}

Step 4: Batch Operations

// Batch creates are much faster than individual creates
async function createKeysBatched(
  projectId: string,
  keys: any[],
  batchSize = 100
): Promise<any[]> {
  const results: any[] = [];

  for (let i = 0; i < keys.length; i += batchSize) {
    const batch = keys.slice(i, i + batchSize);

    const result = await client.keys().create({
      project_id: projectId,
      keys: batch,
    });

    results.push(...result.items);

    // Small delay to respect rate limits
    await new Promise(r => setTimeout(r, 200));
  }

  return results;
}

// DataLoader for automatic batching
import DataLoader from "dataloader";

const keyLoader = new DataLoader<string, any>(
  async (keyIds) => {
    // Batch fetch keys
    const result = await client.keys().list({
      project_id: projectId,
      filter_key_ids: keyIds.join(","),
    });

    // Return in same order as requested
    return keyIds.map(id =>
      result.items.find(k => k.key_id.toString() === id) || null
    );
  },
  {
    maxBatchSize: 100,
    batchScheduleFn: callback => setTimeout(callback, 10),
  }
);

Step 5: Parallel Downloads with Rate Limiting

import PQueue from "p-queue";

const queue = new PQueue({
  concurrency: 5,
  interval: 1000,
  intervalCap: 5,
});

async function downloadMultipleProjects(projectIds: string[]) {
  return Promise.all(
    projectIds.map(id =>
      queue.add(() =>
        client.files().download(id, {
          format: "json",
          original_filenames: false,
        })
      )
    )
  );
}

Output

• Compression enabled for faster transfers
• Response caching implemented
• Cursor pagination for large datasets
• Batch operations for bulk changes

Error Handling

Examples

Redis Caching (Distributed)

import Redis from "ioredis";

const redis = new Redis(process.env.REDIS_URL);

async function cachedWithRedis<T>(
  key: string,
  fetcher: () => Promise<T>,
  ttlSeconds = 60
): Promise<T> {
  const cached = await redis.get(key);
  if (cached) {
    return JSON.parse(cached);
  }

  const result = await fetcher();
  await redis.setex(key, ttlSeconds, JSON.stringify(result));
  return result;
}

// Stale-while-revalidate pattern
async function staleWhileRevalidate<T>(
  key: string,
  fetcher: () => Promise<T>,
  staleTtl = 60,
  maxTtl = 3600
): Promise<T> {
  const cached = await redis.get(key);

  if (cached) {
    const { data, timestamp } = JSON.parse(cached);
    const age = (Date.now() - timestamp) / 1000;

    if (age < staleTtl) {
      return data;  // Fresh
    }

    if (age < maxTtl) {
      // Stale but usable - revalidate in background
      revalidate(key, fetcher, staleTtl, maxTtl);
      return data;
    }
  }

  // Cache miss or expired - fetch fresh
  return revalidate(key, fetcher, staleTtl, maxTtl);
}

async function revalidate<T>(
  key: string,
  fetcher: () => Promise<T>,
  staleTtl: number,
  maxTtl: number
): Promise<T> {
  const data = await fetcher();
  await redis.setex(key, maxTtl, JSON.stringify({
    data,
    timestamp: Date.now(),
  }));
  return data;
}

Performance Monitoring

async function measuredRequest<T>(
  operation: string,
  fn: () => Promise<T>
): Promise<T> {
  const start = performance.now();

  try {
    const result = await fn();
    const duration = performance.now() - start;

    console.log({
      operation,
      duration: `${duration.toFixed(2)}ms`,
      status: "success",
    });

    // Report to metrics
    await reportMetric("lokalise_request_duration", duration, {
      operation,
      status: "success",
    });

    return result;
  } catch (error: any) {
    const duration = performance.now() - start;

    console.error({
      operation,
      duration: `${duration.toFixed(2)}ms`,
      status: "error",
      error: error.message,
    });

    await reportMetric("lokalise_request_duration", duration, {
      operation,
      status: "error",
    });

    throw error;
  }
}

Preloading Translations

// Preload translations during app startup
async function preloadTranslations(
  projectId: string,
  locales: string[]
): Promise<Map<string, any>> {
  const translations = new Map();

  // Download all in parallel
  const downloads = await Promise.all(
    locales.map(async (locale) => {
      const result = await cachedWithRedis(
        `translations:${projectId}:${locale}`,
        () => fetchTranslationsForLocale(projectId, locale),
        3600  // 1 hour cache
      );
      return { locale, translations: result };
    })
  );

  for (const { locale, translations: trans } of downloads) {
    translations.set(locale, trans);
  }

  return translations;
}

Resources

• Lokalise API Rate Limits
• Node SDK Documentation
• DataLoader Documentation

Next Steps

For cost optimization, see lokalise-cost-tuning.