Fetching All Pages from a Paginated REST API

async function fetchAllPaginatedData(url, initialPage = 1, allItems = []) {
  try {
    const response = await fetch(`${url}?page=${initialPage}`);
    if (!response.ok) {
      throw new Error(`HTTP error! status: ${response.status}`);
    }
    const data = await response.json();

    // Assuming the API returns data in 'items' and has 'totalPages' or a 'next' link
    const items = data.items || data.results; // Adjust based on your API response structure
    const totalPages = data.totalPages || data.meta?.pagination?.pages; // Or similar
    const nextPageLink = data.next_page_link; // If using link-based pagination

    if (items && items.length > 0) {
      allItems.push(...items);
    }

    // Determine if there's a next page based on totalPages or a next link
    if (nextPageLink) {
      // For link-based pagination
      const nextUrl = new URL(nextPageLink);
      const nextPage = nextUrl.searchParams.get('page'); // Extract page number
      return fetchAllPaginatedData(url, parseInt(nextPage), allItems);
    } else if (totalPages && initialPage < totalPages) {
      // For page number-based pagination
      return fetchAllPaginatedData(url, initialPage + 1, allItems);
    } else {
      return allItems; // All pages fetched
    }
  } catch (error) {
    console.error("Error fetching paginated data:", error);
    throw error; // Re-throw to allow caller to handle
  }
}

// Example usage:
// (async () => {
//   try {
//     const allPosts = await fetchAllPaginatedData('https://api.example.com/posts');
//     console.log('All fetched posts:', allPosts);
//   } catch (error) {
//     console.error('Failed to get all posts.');
//   }
// })();