wikipedia-summary/index.js

Wikipedia API wrapper — summaries, search, random articles, On This Day events, multi-language support.

const fetch = require("node-fetch");

/**
 * Fetches a Wikipedia summary for a given topic.
 * @param {string} topic - The topic to search for.
 * @param {string} [lang="en"] - The language code (default: "en").
 * @returns {Promise<Object>} - Wikipedia summary including title, description, extract, and image.
 */
async function getSummary(topic, lang = "en") {
  try {
    if (!topic || typeof topic !== "string") {
      throw new Error("A valid topic string is required.");
    }

    const url = `https://${lang}.wikipedia.org/api/rest_v1/page/summary/${encodeURIComponent(topic)}`;
    const response = await fetch(url);
    const data = await response.json();

    if (data?.title === "Not found.") {
      throw new Error("Topic not found on Wikipedia. Please try another search term.");
    }
    
    if (!response.ok) {
      throw new Error(`HTTP error! Status: ${response.status}`);
    }

    return {
      title: data.title,
      description: data.description || "No description available.",
      extract: data.extract || "No summary available.",
      pageUrl: data.content_urls?.desktop?.page || `https://${lang}.wikipedia.org/wiki/${encodeURIComponent(topic)}`,
      imageUrl: data.originalimage?.source || null,
      thumbnailUrl: data.thumbnail?.source || null,
      language: lang,
      type: data.type || "standard",
      lastModified: data.timestamp || null,
    };
  } catch (error) {
    throw new Error(`Error fetching Wikipedia summary: ${error.message}`);
  }
}

/**
 * Searches Wikipedia for matching articles.
 * @param {string} query - Search query.
 * @param {string} [lang="en"] - Language code.
 * @param {number} [limit=10] - Max results (1-50).
 * @returns {Promise<Object[]>} - Array of search results with title, description, and URL.
 */
async function search(query, lang = "en", limit = 10) {
  try {
    if (!query || typeof query !== "string") {
      throw new Error("A valid search query is required.");
    }

    limit = Math.min(Math.max(limit, 1), 50);
    const url = `https://${lang}.wikipedia.org/w/api.php?action=query&list=search&srsearch=${encodeURIComponent(query)}&srlimit=${limit}&format=json&origin=*`;
    const response = await fetch(url);

    if (!response.ok) {
      throw new Error(`HTTP error! Status: ${response.status}`);
    }

    const data = await response.json();

    if (!data.query?.search) return [];

    return data.query.search.map((item) => ({
      title: item.title,
      snippet: item.snippet.replace(/<[^>]+>/g, ""), // Strip HTML
      wordCount: item.wordcount,
      pageUrl: `https://${lang}.wikipedia.org/wiki/${encodeURIComponent(item.title)}`,
    }));
  } catch (error) {
    throw new Error(`Wikipedia search failed: ${error.message}`);
  }
}

/**
 * Gets a random Wikipedia article summary.
 * @param {string} [lang="en"] - Language code.
 * @returns {Promise<Object>} - Random article summary.
 */
async function getRandomArticle(lang = "en") {
  try {
    const url = `https://${lang}.wikipedia.org/api/rest_v1/page/random/summary`;
    const response = await fetch(url);

    if (!response.ok) {
      throw new Error(`HTTP error! Status: ${response.status}`);
    }

    const data = await response.json();

    return {
      title: data.title,
      description: data.description || "No description available.",
      extract: data.extract || "No summary available.",
      pageUrl: data.content_urls?.desktop?.page || null,
      imageUrl: data.originalimage?.source || null,
      thumbnailUrl: data.thumbnail?.source || null,
      language: lang,
    };
  } catch (error) {
    throw new Error(`Random article fetch failed: ${error.message}`);
  }
}

/**
 * Gets "On this day" events from Wikipedia.
 * @param {string} [lang="en"] - Language code.
 * @param {string} [type="all"] - Type: "all", "selected", "births", "deaths", "events", "holidays".
 * @returns {Promise<Object[]>} - Array of on-this-day entries.
 */
async function getOnThisDay(lang = "en", type = "all") {
  try {
    const now = new Date();
    const month = String(now.getMonth() + 1).padStart(2, "0");
    const day = String(now.getDate()).padStart(2, "0");
    const url = `https://${lang}.wikipedia.org/api/rest_v1/feed/onthisday/${type}/${month}/${day}`;
    const response = await fetch(url);

    if (!response.ok) {
      throw new Error(`HTTP error! Status: ${response.status}`);
    }

    const data = await response.json();

    // Combine all event types
    const events = [];
    for (const key of Object.keys(data)) {
      if (Array.isArray(data[key])) {
        data[key].forEach((item) => {
          events.push({
            type: key,
            text: item.text,
            year: item.year || null,
            pages: item.pages?.map((p) => ({
              title: p.title,
              description: p.description || null,
              pageUrl: p.content_urls?.desktop?.page || null,
            })) || [],
          });
        });
      }
    }

    return events;
  } catch (error) {
    throw new Error(`On This Day fetch failed: ${error.message}`);
  }
}

/**
 * Gets multiple summaries at once.
 * @param {string[]} topics - Array of topics.
 * @param {string} [lang="en"] - Language code.
 * @returns {Promise<Object[]>} - Array of summaries.
 */
async function getMultipleSummaries(topics, lang = "en") {
  if (!Array.isArray(topics) || topics.length === 0) {
    throw new Error("Please provide an array of topics.");
  }

  const results = await Promise.allSettled(
    topics.map((topic) => getSummary(topic, lang))
  );

  return results.map((result, index) => {
    if (result.status === "fulfilled") {
      return result.value;
    }
    return { title: topics[index], error: result.reason.message };
  });
}

module.exports = { getSummary, search, getRandomArticle, getOnThisDay, getMultipleSummaries };