Question

接口调用凭证 access_token 的缓存与更新

https://developers.weixin.qq.com/miniprogram/dev/api-backend/open-api/access-token/auth.getAccessToken.html

const fs = require('fs')
const path = require('path')
const rp = require('request-promise')
const {APPID,SECRET} = require('./config')

const fileName = path.resolve(__dirname, './access_token.json')

/**
 * 每个接口调用都需要 access_token
 */

const URL = `https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=${APPID}&secret=${SECRET}`

// ![](https://blog.poetries.top/img/static/images/20210905185325.png)
const updateAccessToken = async ()=>{
  const resStr = await rp(URL)
  const res = JSON.parse(resStr)
  if(res.access_token) {
    fs.writeFileSync(fileName,JSON.stringify({
      access_token: res.access_token,
      createTime: new Date()
    }))
  }else{
    await updateAccessToken()
  }
}

const getAccessToken = async ()=>{
  try {
    const res = fs.readFileSync(fileName, 'utf8')
    const obj = JSON.parse(res)
    const createTime = new Date(obj.createTime).getTime()
    const nowTime = new Date().getTime()
    if((nowTime - createTime) / 1000 / 60 / 60 >= 2) {
      // token 过期
      await updateAccessToken()
      await getAccessToken()
    }
    return obj.access_token
  } catch (error) {
    await updateAccessToken()
    await getAccessToken()
  }
}

// setInterval(async () => {
//   await updateAccessToken()
  // 在 2 小时上减去 5 分钟 提前刷新 token 平滑过渡
// }, (7200 - 300)*1000);

const getAccessToken2 = async ()=>{
  try {
    const resStr = await rp(URL)
    const res = JSON.parse(resStr)
  
    return res.access_token
  } catch (error) {
    return ''
  }
}

module.exports = getAccessToken2

HTTP API 触发云函数

https://developers.weixin.qq.com/miniprogram/dev/wxcloud/reference-http-api/functions/invokeCloudFunction.html

// utils/callCloudFn

const getAccessToken = require('./getAccessToken')
const rp = require('request-promise')

/**
 * 调用云函数方法
 * @param {d} ctx 
 * @param {*} fnName 
 * @param {*} params 
 * @returns 
 */
const callCloudFn = async (ctx, fnName, params) =>{
  const ACCESS_TOKEN = await getAccessToken()
  const options = {
    method: 'POST',
    uri: `https://api.weixin.qq.com/tcb/invokecloudfunction?access_token=${ACCESS_TOKEN}&env=${ctx.env}&name=${fnName}`,
    body: {
      ...params
    },
    json: true
  }
  return await rp(options).then(res=>JSON.parse(res.resp_data).data)
}

module.exports = callCloudFn

// utils/callCloudStorage

const getAccessToken = require('./getAccessToken')
const rp = require('request-promise')
const fs = require('fs')

/**
 * 获取文件下载链接 把 fileId 转化成 http 地址
 */
const callCloudStorage = {
  async download(ctx,fileList) {
    const ACCESS_TOKEN = await getAccessToken()
    const options = {
      method: 'POST',
      uri: `https://api.weixin.qq.com/tcb/batchdownloadfile?access_token=${ACCESS_TOKEN}`,
      body: {
        "file_list": fileList,
        "env": ctx.env
      },
      json: true
    }
    return await rp(options).then(res=>res)
  },
  // 上传图片
  async upload(ctx) {
    const ACCESS_TOKEN = await getAccessToken()
    const file = ctx.request.files.file

    // 上传到云存储指定文件夹 blog
    const path = `day/${Date.now()}-${Math.random()}-${file.name}`
    const options = {
      method: 'POST',
      uri: `https://api.weixin.qq.com/tcb/uploadfile?access_token=${ACCESS_TOKEN}`,
      body: {
        "path": path,
        "env": ctx.env
      },
      json: true
    }
    const info = await rp(options).then(res=>res)

    console.log(info,'----upload info----')

    // 2 上传图片
    const params = {
      method: "POST",
      headers: {
        'content-type': "multipart/form-data"
      },
      uri: info.url,
      formData: {
        key: path,
        Signature: info.authorization,
        'x-cos-security-token': info.token,
        'x-cos-meta-fileid': info.cos_file_id,
        file: fs.createReadStream(file.path)
      },
      json: true
    }
    await rp(params)

    return info.file_id
  },
  // 删除云储存图片
  async delete(ctx, fileid_list) {
    const ACCESS_TOKEN = await getAccessToken()
    const file = ctx.query.file 
    // 上传到云存储指定文件夹 blog
    const path = `blog/${Date.now()}-${Math.random()}-${file}`
    const options = {
      method: 'POST',
      uri: `https://api.weixin.qq.com/tcb/batchdeletefile?access_token=${ACCESS_TOKEN}`,
      body: {
        "fileid_list": fileid_list,
        "env": ctx.env
      },
      json: true
    }
    return await rp(options).then(res=>res)
  }
}

module.exports = callCloudStorage

// 使用

router.get('/day/list', async (ctx, next) => {
  const data = await callCloudFn(ctx, 'day', {
    $url: 'list',
    pageSize: 30,
    pageNum: 0
  })

  // 文件下载链接 cloud=>http 格式
  let fileList = []
  data.forEach(v=>{
    if(v.image.indexOf('cloud://') > -1) {
      fileList.push({
        fileid: v.image,
        max_age: 7200
      })
    }
  })
  
  if(fileList.length) {
    const downloadRes = await callCloudStorage.download(ctx,fileList)
    const downloadFileList = downloadRes.file_list || []
    
    downloadFileList.forEach(v=>{
      data.forEach(vv=>{
        if(v.fileid === vv.image) {
          // 获取云存储的 http 图片路径
          vv.image = v.download_url
        }
      })
    })
  }
  

  ctx.body = {
    data,
    code: 200
  }
})