官方文檔：https://developers.weixin.qq.com/miniprogram/dev/wxcloud/guide/functions/openapi.html

支持接口：https://developers.weixin.qq.com/miniprogram/dev/api-backend/index.html

一、創(chuàng)建云函數(shù)并配置相應(yīng)的權(quán)限

image.png

{
  "permissions": {
    "openapi": [
      "wxacode.getUnlimited"
    ]
  }
}

必須配置相關(guān)的調(diào)用權(quán)限瓦戚，否則無法正常調(diào)用

二吼砂、編寫云函數(shù)

1留荔、生成二維碼

2涣旨、上傳到云存儲(chǔ)

3怜奖、獲取臨時(shí)地址（有效期最多一天）

// 云調(diào)用~生成小程序二維碼
const cloud = require('wx-server-sdk')
cloud.init()
exports.main = async(event, context) => {

  var scene = event.scene;
  var page = event.page;
  var width = event.width;

  try {
    // 1妖胀、通過云調(diào)用生成二維碼
    const result = await cloud.openapi.wxacode.getUnlimited({
      scene: scene,
      page: page,
      width: width
    })
    console.log(result)
    // 2峦剔、上傳圖片到云存儲(chǔ)
    const upload = await cloud.uploadFile({
      cloudPath: scene + '.jpg',
      fileContent: result.buffer,
    })
    console.log(upload)
    // 3档礁、返回圖片地址
    var fileID = upload.fileID;
    console.log("fileId=" + fileID);

    const fileList = [fileID]
    const imgList = await cloud.getTempFileURL({
      fileList: fileList,
    })
    return imgList.fileList
  } catch (err) {
    console.log(err)
    return err
  }
}

三、調(diào)用云函數(shù)

注意：頁(yè)面地址不能帶參數(shù)吝沫，否則報(bào)錯(cuò)

    var path = 'pages/add_grade/add_grade' 
    var width = '430';

    wx.cloud.callFunction({
      name: 'generateEWM',
      data: {
        page: path,
        width: width,
        scene: objectId,
      },
      success: res => {
        console.log(res)

        wx.showToast({
          title: '生成成功!',
        })

      },
      fail: error => {
        console.log(JSON.stringify(error))
        wx.showToast({
          title: '生成失敗!',
        })
      }
    });

返回JSON

{
    "errMsg": "cloud.callFunction:ok",
    "result": [{
        "fileID": "cloud://release-3ea42b.7265-release-3ea42b-1258370407/9c4488c75cb7d2930121b6e46c3cefdb.jpg",
        "status": 0,
        "errMsg": "ok",
        "tempFileURL": "https://7265-release-3ea42b-1258370407.tcb.qcloud.la/9c4488c75cb7d2930121b6e46c3cefdb.jpg"
    }],
    "requestID": "c4a20658-6181-11e9-818b-525400235f2a"
}

image.png