upgrade to 3.0

_data/webmentions.js

@@ -0,0 +1,96 @@
+import fs from "fs";
+import fetch from "node-fetch";
+import unionBy from "lodash-es/unionBy.js";
+import domain from "./metadata.js";
+
+// Load .env variables with dotenv
+import "dotenv/config.js";
+
+// Configuration Parameters
+const CACHE_DIR = '_cache';
+const API_ORIGIN = 'https://webmention.io/api/mentions.jf2';
+const TOKEN = process.env.WEBMENTION_IO_TOKEN;
+
+async function fetchWebmentions(since, perPage = 10000) {
+  // If we don't have a domain name or token, abort
+  if (!domain || !TOKEN) {
+	console.warn('>>> unable to fetch webmentions: missing domain or token');
+	return false;
+  }
+
+  let url = `${API_ORIGIN}?domain=${domain}&token=${TOKEN}&per-page=${perPage}`;
+  if (since) url += `&since=${since}`; // only fetch new mentions
+
+  const response = await fetch(url);
+  if (response.ok) {
+	const feed = await response.json();
+	console.log(`>>> ${feed.children.length} new webmentions fetched from ${API_ORIGIN}`);
+	return feed;
+  }
+
+  return null;
+}
+
+// Merge fresh webmentions with cached entries, unique per id
+function mergeWebmentions(a, b) {
+  return unionBy(a.children, b.children, 'wm-id');
+}
+
+// save combined webmentions in cache file
+function writeToCache(data) {
+  const filePath = `${CACHE_DIR}/webmentions.json`;
+  const fileContent = JSON.stringify(data, null, 2);
+
+  // create cache folder if it doesnt exist already
+  if (!fs.existsSync(CACHE_DIR)) {
+	fs.mkdirSync(CACHE_DIR);
+  }
+  // write data to cache json file
+  fs.writeFile(filePath, fileContent, err => {
+	if (err) throw err;
+	console.log(`>>> webmentions cached to ${filePath}`);
+  });
+}
+
+// get cache contents from json file
+function readFromCache() {
+  const filePath = `${CACHE_DIR}/webmentions.json`;
+
+  if (fs.existsSync(filePath)) {
+	const cacheFile = fs.readFileSync(filePath);
+	return JSON.parse(cacheFile);
+  };
+  // no cache found
+  return {
+	lastFetched: null,
+	children: []
+  };
+}
+
+export default async function() {
+  console.log('>>> Reading webmentions from cache...');
+
+  const cache = readFromCache();
+
+  if (cache.children.length) {
+    console.log(`>>> ${cache.children.length} webmentions loaded from cache`);
+  };
+
+  // Only fetch new mentions in production
+  if (process.env.ELEVENTY_ENV === 'production') {
+    console.log('>>> Checking for new webmentions...');
+	const feed = await fetchWebmentions(cache.lastFetched);
+
+	if (feed) {
+	  const webmentions = {
+		lastFetched: new Date().toISOString(),
+		children: mergeWebmentions(cache, feed)
+	  }
+
+	  writeToCache(webmentions);
+	  return webmentions;
+	}
+  }
+
+  return cache;
+}