Cloud.getWXContext(): Object

Support side: Cloud function

Get the WeChat call context in the cloud function

Returns a value

Object

wxContext

Instructions for use

The SOURCE value follows the call chain pass, which indicates the call link situation (separated by an English comma), such as a small program calling the cloud function A, and then calling the cloud function B within the cloud function A, A gets the SOURCE as wx_client, and the SOURCE obtained within B is wx_client, scf (weChat small program calls, and then the cloud function calls).

The enumerus type of SOURCE:

If ENV is local and SOURCE is local in on-premises debugging of wx_client.

Precautions

Do not use getWXContext outside of exports.main, this fashion does not call context and cannot get information.

Sample code

const cloud = require('wx-server-sdk')

exports.main = async (event, context) => {
  const {
    OPENID,
    APPID,
    UNIONID,
    ENV,
  } = cloud.getWXContext()

  return {
    OPENID,
    APPID,
    UNIONID,
    ENV,
  }
}

Cloud.logger(): Object

Support side: Cloud function 1.5.0

Use advanced logging capabilities in cloud functions

Returns a value

Object

logger

Instructions for use

Used to use advanced logging capabilities.

The logger method returns a log object that contains the following method, generating one log record per call: log: log info: normal-grade log warn: warning-level log error: error-level log

All methods receive an object, and each of the object's key, value, and pairs is a retrievable pair of key values for a log record, where value is automatically converted to a string regardless of type

The sample code

// 云函数入口文件
const cloud = require('wx-server-sdk')
cloud.init({
  env: cloud.DYNAMIC_CURRENT_ENV,
})
// 云函数入口函数
exports.main = async (event, context) => {
  const wxContext = cloud.getWXContext()

  const log = cloud.logger()
  log.info({
    name: 'xx',
    cost: 10,
    attributes: {
      width: 100,
      height: 200,
    },
    colors: ['red', 'blue'],
  })

  // 输出到日志记录中会有这么一条记录：
  // {
  //   "level": "info",
  //   "name": "xx",
  //   "cost": "10",
  //   "attributes": "{ width: 100, height: 200 }",
  //   "colors": "[ "red", "blue" ]"
  //   ..., // 其他系统字段
  // }

  return {
    event,
    openid: wxContext.OPENID,
    appid: wxContext.APPID,
    unionid: wxContext.UNIONID,
  }
}

Cloud.CDN(opt: string| A rrrayBuffer| Object)

Support side: Small program 2.12.0

The small terminal tuning cloud function passes the temporary CDNs available for big data

Parameters

opt: string| A rrrayBuffer| Object

Instructions for use

Tags data that needs to be uploaded to a CDN file/large string and then converted to an HTTP URL must be used in callFunction.

When a cloud function is called by a small terminal, if you want to pass big data (recommended for more than 128k), you can use this CDN method to mark the data that needs to be passed, between a string and a temporary file path. After the tag, when the cloud function is called, the data is automatically uploaded to the temporary CDN, and the field received within the cloud function will eventually be a CDN address that can be requested within the cloud function.

This method avoids the transmission of big data within the cloud function link, improves the performance of big data calls, and avoids touching the size limit of the calling data.

The CDN method can receive three parameter types:

• String
• ArrayBuffer
• The file path defines the object

When you define an object using a file path, the file content corresponding to the file path is automatically uploaded to the CDN and converted to a CDN URL when the service API is called, and the object is defined as follows:

Receive an object with fields defined below:

The sample code

wx.cloud.callFunction({
  name: 'test',
  data: {
    strDemo: wx.cloud.CDN('some large string'),
    filePathDemo: wx.cloud.CDN({
      type: 'filePath',
      filePath: 'xxxxxxxx',
    })
  },
})
.then(console.log)
.catch(console.error)