Express.js中的自定义回调获取 [英] Custom callback in Express.js get

问题描述

我的app.js中有问题

I have a get in my app.js

app.get('/api/personnel', api.personnel);

调用此函数作为回调以从mongo加载一些数据:

that calls this function as a callback to load some data from mongo:

exports.personnel = function(req, res) {
  var docs;
  db.personnel.find(function(err, docs) {
    if (err) {
      logError(err);
    } else {
      res.json({
        personnel: docs
      });
    }
  });

};

那很好，但是我真的很希望能够在函数完成后调用回调进行测试:

That works just fine, but I'd really like to be able to call a callback for testing purposes when the function is complete:

exports.personnel = function(req, res, callback) {
  var docs;
  db.personnel.find(function(err, docs) {
    if (err) {
      logError(err);
    } else {
      res.json({
        personnel: docs
      });
    }
    callback();
  });

从实时应用程序中调用该函数时，

callback()为空，并给我一个错误:

callback() is empty when the function is called from the live application and gives me a error:

Error: Can't set headers after they are sent.

我该如何让get呼叫我的回调?

How do I go about having a get call my callback?

推荐答案

您只需包装该函数即可插入其他函数参数:

You can just wrap that function to insert the additional function argument:

exports.personnel = function(req, res, callback) {
  var docs;
  db.personnel.find(function(err, docs) {
    if (err) {
      logError(err);
    } else {
      res.json({
        personnel: docs
      });
    }
  });
///////////////////////////////////////////////////

var callback = ...;
pp.get('/api/personnel', function(req, res) {
     api.personnel(req, res, callback);
});

这篇关于Express.js中的自定义回调获取的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！