koa-router处理URL

koa-router处理URL

• koa-router使用的结构

  const Koa = require('koa');
  
  // 注意require('koa-router')返回的是函数:
  const router = require('koa-router')();
  
  const app = new Koa();
  
  // log request URL:
  app.use(async (ctx, next) => {
      console.log(`Process ${ctx.request.method} ${ctx.request.url}...`);
      await next();
  });
  
  // add url-route:
  router.get('/hello/:name', async (ctx, next) => {
      var name = ctx.params.name;   //name是一个变量，通过ctx.params.name访问
      ctx.response.body = `<h1>Hello, ${name}!</h1>`;
  });
  
  router.get('/', async (ctx, next) => {
      ctx.response.body = '<h1>Index</h1>';
  });
  
  // add router middleware:
  app.use(router.routes());
  
  app.listen(3000);
  console.log('app started at port 3000...');
  

  • const router = require('koa-router')(); 对象生成，因为require('koa-router')返回的是函数，后面再加个 () 才得到对象
  • router.get('/path',async fn) 工作逻辑（处理get请求），添加对应url的处理函数
  • app.use(router.routes()); 添加router middleware， router.routes() 返回的就是middleware

• 使用koa-bodyparser解析request的body以处理post请求

  • const bodyParser = require('koa-bodyparser'); 引入koa-bodyparser

  • router.get('/', async (ctx, next) => {
        ctx.response.body = `<h1>Index</h1>
            <form action="/signin" method="post">
                <p>Name: <input name="name" value="koa"></p>
                <p>Password: <input name="password" type="password"></p>
                <p><input type="submit" value="Submit"></p>
            </form>`;
    });
    
    router.post('/signin', async (ctx, next) => {
        var
            name = ctx.request.body.name || '',
            password = ctx.request.body.password || '';
        console.log(`signin with name: ${name}, password: ${password}`);
        if (name === 'koa' && password === '12345') {
            ctx.response.body = `<h1>Welcome, ${name}!</h1>`;
        } else {
            ctx.response.body = `<h1>Login failed!</h1>
            <p><a href="/">Try again</a></p>`;
        }
    });
    

    对于post请求的body解析结果存储再ctx.request.body 中

  • app.use(bodyParser()); 必须添加在app.use(router.routes()); 之前

摘自处理URL(廖雪峰)

url-koa源码

url2-koa源码(重构)