云调用02-生成小程序码

官方文档：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、创建云函数并配置相应的权限

image.png

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

必须配置相关的调用权限，否则无法正常调用

二、编写云函数

1、生成二维码

2、上传到云存储

3、获取临时地址（有效期最多一天）

// 云调用~生成小程序二维码
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、通过云调用生成二维码
    const result = await cloud.openapi.wxacode.getUnlimited({
      scene: scene,
      page: page,
      width: width
    })
    console.log(result)
    // 2、上传图片到云存储
    const upload = await cloud.uploadFile({
      cloudPath: scene + '.jpg',
      fileContent: result.buffer,
    })
    console.log(upload)
    // 3、返回图片地址
    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、调用云函数

注意：页面地址不能带参数，否则报错

    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: '生成失败!',
        })
      }
    });

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