引入mongodb

lib/cache/cache_manager.js

@@ -1,9 +1,13 @@
 import MemoryCache from './memory_cache'
 import FileCache from './local_file_cache'
+import MongoCache from './mongo_db_cache'
 const enableCache = true
+const enableMongoCache = true
 
 let api
-if (process.env.ENABLE_FILE_CACHE) {
+if (enableMongoCache) {
+  api = MongoCache
+} else if (process.env.ENABLE_FILE_CACHE) {
   api = FileCache
 } else {
   api = MemoryCache
@@ -22,7 +26,7 @@ export async function getDataFromCache(key) {
   if (JSON.stringify(dataFromCache) === '[]') {
     return null
   }
-  return dataFromCache
+  return MongoCache.getCache(key)
 }
 
 export async function setDataToCache(key, data) {

lib/cache/mongo_db_cache.js

@@ -0,0 +1,49 @@
+const MongoClient = require('mongodb').MongoClient
+
+const DB_URL = process.env.MONGO_DB_URL // e.g. mongodb+srv://mongo_user:[password]@xxx.mongodb.net//?retryWrites=true&w=majority
+const DB_NAME = process.env.MONGO_DB_NAME // e.g. tangly1024
+const DB_COLLECTION = 'posts'
+
+export async function getCache (key) {
+  const client = await MongoClient.connect(DB_URL).catch(err => { console.error(err) })
+  const dbo = client.db(DB_NAME)
+  const query = { block_id: key }
+  const res = await dbo.collection('posts').findOne(query).catch(err => { console.error(err) })
+  await client.close()
+  return res
+}
+
+/**
+ * 并发请求写文件异常； Vercel生产环境不支持写文件。
+ * @param key
+ * @param data
+ * @returns {Promise<null>}
+ */
+export async function setCache (key, data) {
+  const client = await MongoClient.connect(DB_URL).catch(err => { console.error(err) })
+  const dbo = client.db(DB_NAME)
+  data.block_id = key
+  const query = { block_id: key }
+  const jsonObj = JSON.parse(JSON.stringify(data))
+
+  const updRes = await dbo.collection(DB_COLLECTION).updateOne(query, { $set: jsonObj }).catch(err => { console.error(err) })
+  console.log('更新结果', key, updRes)
+  if (updRes.matchedCount === 0) {
+    const insertRes = await dbo.collection(DB_COLLECTION).insertOne(jsonObj).catch(err => { console.error(err) })
+    console.log('插入结果', key, insertRes)
+  }
+  await client.close()
+  return data
+}
+
+export async function delCache (key, data) {
+  const client = await MongoClient.connect(DB_URL).catch(err => { console.error(err) })
+  const dbo = client.db(DB_NAME)
+  const query = { block_id: key }
+  const res = await dbo.collection('posts').deleteOne(query).catch(err => { console.error(err) })
+  console.log('删除结果', key, res)
+  await client.close()
+  return null
+}
+
+export default { getCache, setCache, delCache }