moves scraper to a subpackage

scraper/lib/cache.js

@@ -0,0 +1,81 @@
+const cacheManager = require('cache-manager');
+const mangodbStore = require('cache-manager-mongodb');
+
+const GLOBAL_KEY_PREFIX = 'stremio-torrentio';
+const IMDB_ID_PREFIX = `${GLOBAL_KEY_PREFIX}|imdb_id`;
+const METADATA_PREFIX = `${GLOBAL_KEY_PREFIX}|metadata`;
+const TORRENT_FILES_KEY_PREFIX = `stremio-tpb|files`;
+
+const GLOBAL_TTL = process.env.METADATA_TTL || 7 * 24 * 60 * 60; // 7 days
+const MEMORY_TTL = process.env.METADATA_TTL || 2 * 60 * 60; // 2 hours
+
+const MONGO_URI = process.env.MONGODB_URI;
+
+const memoryCache = initiateMemoryCache();
+const remoteCache = initiateRemoteCache();
+const torrentFilesCache = initiateTorrentFilesCache();
+
+function initiateTorrentFilesCache() {
+  if (MONGO_URI) {
+    return cacheManager.caching({
+      store: mangodbStore,
+      uri: MONGO_URI,
+      options: {
+        collection: 'cacheManager',
+      },
+      ttl: GLOBAL_TTL,
+      ignoreCacheErrors: true
+    });
+  }
+}
+
+function initiateRemoteCache() {
+  if (MONGO_URI) {
+    return cacheManager.caching({
+      store: mangodbStore,
+      uri: MONGO_URI,
+      options: {
+        collection: 'torrentio_scraper_collection',
+      },
+      ttl: GLOBAL_TTL,
+      ignoreCacheErrors: true
+    });
+  } else {
+    return cacheManager.caching({
+      store: 'memory',
+      ttl: GLOBAL_TTL
+    });
+  }
+}
+
+function initiateMemoryCache() {
+  return cacheManager.caching({
+    store: 'memory',
+    ttl: MEMORY_TTL
+  });
+}
+
+function retrieveTorrentFiles(infoHash) {
+  return torrentFilesCache.get(`${TORRENT_FILES_KEY_PREFIX}:${infoHash}`)
+      .then((results) => {
+        if (!results) {
+          throw new Error('No cached files found');
+        }
+        return results;
+      });
+}
+
+function cacheWrap(cache, key, method, options) {
+  return cache.wrap(key, method, options);
+}
+
+function cacheWrapImdbId(key, method) {
+  return cacheWrap(remoteCache, `${IMDB_ID_PREFIX}:${key}`, method, { ttl: GLOBAL_TTL });
+}
+
+function cacheWrapMetadata(id, method) {
+  return cacheWrap(memoryCache, `${METADATA_PREFIX}:${id}`, method, { ttl: GLOBAL_TTL });
+}
+
+module.exports = { cacheWrapImdbId, cacheWrapMetadata, retrieveTorrentFiles };
+