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when middleware meet setTimeout, ctx.body don't work ?

See original GitHub issue

app.use((ctx, next) => {  
  console.log('1')
  setTimeout(function(){

    console.log('2')
    return next().then(() => {
      // after
      console.log('3')
    })
  }, 1000)  
});


// response
app.use(ctx => {
  console.log('业务逻辑处理')
  ctx.body = 'i am body'
});

when visit

$ curl http://127.0.0.1:3000
Not Found%

Issue Analytics

State:
Created 7 years ago
Comments:13 (9 by maintainers)

Top GitHub Comments

10reactions

chentsulincommented, May 18, 2016

You should return Promise in middleware

app.use((ctx, next) => {  
  console.log('1');
  return new Promise(resolve => {
    setTimeout(resolve, 1000);
  })
  .then(() => {
      console.log('2');
      return next().then(() => {
        // after
        console.log('3');
      });
  });
});

// response
app.use(ctx => {
  console.log('业务逻辑处理');
  ctx.body = 'i am body';
});

Much better with async await:

app.use(async (ctx, next) => {  
  console.log('1');
  await new Promise(resolve => {
    setTimeout(resolve, 1000);
  });
  console.log('2');
  await next();
  // after
  console.log('3');
});

// response
app.use(ctx => {
  console.log('业务逻辑处理');
  ctx.body = 'i am body';
});

3reactions

juliangrubercommented, May 19, 2016

random your mum joke