Initial commit

cloudfunctions/likePost/index.js

@@ -0,0 +1,54 @@
+const cloud = require('wx-server-sdk')
+cloud.init({ env: cloud.DYNAMIC_CURRENT_ENV })
+const db = cloud.database()
+const _ = db.command
+
+exports.main = async (event, context) => {
+  const { OPENID } = cloud.getWXContext()
+  const { postId } = event
+
+  if (!postId) return { code: -1, message: '缺少 postId' }
+
+  try {
+    // 检查是否已点赞
+    const existRes = await db.collection('likes')
+      .where({ userId: OPENID, postId })
+      .get()
+
+    let liked
+    let delta
+
+    if (existRes.data.length > 0) {
+      // 取消点赞
+      await db.collection('likes').doc(existRes.data[0]._id).remove()
+      delta = -1
+      liked = false
+    } else {
+      // 点赞
+      await db.collection('likes').add({
+        data: {
+          userId: OPENID,
+          postId,
+          createdAt: db.serverDate(),
+        },
+      })
+      delta = 1
+      liked = true
+    }
+
+    // 原子更新帖子点赞数
+    await db.collection('posts').doc(postId).update({
+      data: { likeCount: _.inc(delta) },
+    })
+
+    // 获取最新计数
+    const postRes = await db.collection('posts').doc(postId).field({ likeCount: true }).get()
+
+    return {
+      code: 0,
+      data: { liked, count: postRes.data.likeCount },
+    }
+  } catch (e) {
+    return { code: -1, message: e.message }
+  }
+}