angular.js、xterm.js与websocket实现w

概述：webssh泛指一种技术可以在网页上实现一个SSH终端，从而无需Xshell之类的模拟终端工具进行SSH连接。经查阅，显示控制台这个操作页面采用xterm.js（https://xtermjs.org/）实现。前后端交互通过websocket实现。

实现：

1.下载xterm：npm install --save xterm

2.页面引入：import { Terminal } from 'xterm';

3.前端代码：
webssh.component.ts

import { Component, OnInit } from '@angular/core';
import { Terminal } from 'xterm';
// import 'xterm/css/xterm.css'; //踩坑：xterm的css一定要引入，不然页面显示异常。引入位置是放在最外层style.css里的：@import "./node_modules/xterm/css/xterm";

@Component({
  selector: 'app-webssh',
  templateUrl: './webssh.component.html',
  styleUrls: ['./webssh.component.scss']
})
export class WebsshComponent implements OnInit {

  // public term: Terminal;

  constructor() { }

  ngOnInit() {
  }

  // 页面点击事件，显示webssh，与websocket交互
  createServer = () => {
    // 创建一个新的Terminal对象
    const term = new Terminal({
      'cursorBlink': true,
    });
    // 挂载到终端的Dom元素，打开终端
    term.open(document.getElementById('terminal'));
    term.onData(function (data) {
      const msg = { operation: 'stdin', data: data };
      conn.send(JSON.stringify(msg));
    });
    const url = 'ws://xxx';
    const conn = new WebSocket(url);
    // 连接建立时触发
    conn.onopen = function (e) {
     // 写入客户端
      term.write('\r');
      const msg = { operation: 'stdin', data: 'export TERM=xterm && clear \r' };
      conn.send(JSON.stringify(msg));
      term.clear();
    };
    // 客户端接收服务端数据时触发
    conn.onmessage = function (event) {
      const msg = JSON.parse(event.data);
      if (msg.operation === 'stdout') {
        term.write(msg.data);
      } else {
        console.log('invalid msg operation: ' + msg);
      }
    };

    //  连接关闭时触发
    conn.onclose = function (event) {
      if (event.wasClean) {
        console.log(`[close] Connection closed cleanly, code=${event.code} reason=${event.reason}`);
      } else {
        console.log('[close] Connection died');
        term.writeln('');
      }
      term.write('Connection Reset By Peer! Try Refresh.');
    };

    // 通信发生错误时触发
    conn.onerror = function (error) {
      console.log('[error] Connection error');
      term.write('error: ' + error);
      term.clear();
    };

  }

}

webssh.component.html

<div>
  <button nz-button [nzType]="'primary'" (click)="createServer()">
    <i class="anticon anticon-plus"></i>连接
  </button>
  <div id='terminal'></div>
</div>

4.页面效果

PS：若有错误或考虑不周之处，敬请指正！