Coap 服务器搭建 NodeJs版本

版本

• Ubuntu 20.04
• nvm: 0.39.0
• nodejs: v16.13.0
• node-coap

Step1 安装nvm

curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.39.0/install.sh | bash
# 如果无法下载 请执行以下三步
# 1. 前往 https://www.ipaddress.com/ 查询 raw.githubusercontent.com 的 ip
# 2. 修改 /etc/hosts, 增加 ip 域名映射
# 185.199.108.133 raw.githubusercontent.com
# 3. 再次执行命令

nvm --version # 查看nvm版本
# 0.39.0
nvm ls-remote # 查看可用的nodejs版本

Step2 安装nodes

nvm install v16.13.0 # 安装nodejs
node # 查看node，Ctrl-D 退出
# Computing checksum with sha256sum
# Checksums matched!
# Now using node v16.13.0 (npm v8.1.0)
# Creating default alias: default -> v16.13.0
# root@ecs-s6-large-2-linux-20200215160452:~# node
# Welcome to Node.js v16.13.0.
# Type ".help" for more information.
# (To exit, press Ctrl+C again or Ctrl+D or type .exit)

Step3 安装coap

npm install coap --save
# added 24 packages in 3s
# npm notice 
# npm notice New patch version of npm available! 8.1.0 -> 8.1.4
# npm notice Changelog: # # https://github.com/npm/cli/releases/tag/v8.1.4
# npm notice Run npm install -g npm@8.1.4 to update!
# npm notice 

Step4 编写服务端程序

vim server.js

const coap = require('coap')
const server = coap.createServer()

server.on('request', (req, res) => {
  res.end('Hello ' + req.url.split('/')[1] + '\n')
})

// the default CoAP port is 5683
server.listen(() => {
  const req = coap.request('coap://localhost/Matteo')

  req.on('response', (res) => {
    res.pipe(process.stdout)
    res.on('end', () => {
      process.exit(0)
    })
  })

  req.end()
})

Step5 编写客户端程序

vim client.js

const coap  = require('coap') 
const req = coap.request('coap://localhost/cal12345678')
req.on('response', function(res) {
  res.pipe(process.stdout)
})
req.end()

Step6 启动测试运行

node server.js # 在终端1打开
# root@ecs-s6-large-2-linux-20200215160452:~/cope# node server.js 
# server started
node client.js # 在新的终端打开
# root@ecs-s6-large-2-linux-20200215160452:~/cope# node client.js 
# Hello cal12345678