Question

我正在尝试编写几个端点，这些端点将对各种后端服务进行GET和POST http请求，数据格式都非常相似，因此responseHandler函数将被反复复制到不同的路由函数，我想知道是否有办法将responseHandler外部化以便重用。我试图把它移出去，但后来我会失去对res的引用。任何人都有关于更模块化设计的任何提示吗？

routes['/endpoint'] = function(req, res){
    console.log("Serving endpoint: /endpoint")
    var params={"param": "param-value"}

    var options = {
      host: 'localhost',
      path: '/service?param='+params.param,
      method: 'GET'
    };

    var responseHandler = function(response) {
      var data = '';

      // keep track of the data you receive
      response.on('data', function(chunk) {
        data += chunk + "\n";
      });

      // finished? ok, send the data to the client in JSON format
      response.on('end', function() {
            res.header("Content-Type:","application/json");
            res.end(data);
      });
    };

    // make the request, and then end it, to close the connection
    http.request(options, responseHandler).end();
};

Answer 1

通常我认为你可以在你的lib中创建一个名为responseHandlers的文件夹，添加一个包含类似

的文件

var responseHandler = function(response) {
  var data = '';

  // keep track of the data you receive
  response.on('data', function(chunk) {
    data += chunk + "\n";
  });

  // finished? ok, send the data to the client in JSON format
  response.on('end', function() {
        res.header("Content-Type:","application/json");
        res.end(data);
  });
};
exports.Handler = responseHandler;

将其保存为whateverHandler.js，然后创建一个index.js文件，该文件需要whatever.js并将其导出为Handler。这样，如果您需要在将来添加更多处理程序，您只需添加文件并更新index.js。使用，在路由处理程序中执行某些操作，如

var handler = require('./lib/responseHandlers').whateverHandler;
routes['/endpoint'] = function(req, res){
    console.log("Serving endpoint: /endpoint")
    var params={"param": "param-value"}

    var options = {
      host: 'localhost',
      path: '/service?param='+params.param,
      method: 'GET'
    };
};

// make the request, and then end it, to close the connection
http.request(options, handler).end();
};

Answer 2

您可以将responseHandler转换为函数生成器，然后传入res对象，这样就不会丢失它：

var responseHandler = function(res) {
  return function(response) {
    var data = '';

    // keep track of the data you receive
    response.on('data', function(chunk) {
      data += chunk + "\n";
    });

    // finished? ok, send the data to the client in JSON format
    response.on('end', function() {
          res.header("Content-Type:","application/json");
          res.end(data);
    });
  };
}

并像这样使用它：

routes['/endpoint'] = function(req, res){
    console.log("Serving endpoint: /endpoint")
    var params={"param": "param-value"}

    var options = {
      host: 'localhost',
      path: '/service?param='+params.param,
      method: 'GET'
    };

    // make the request, and then end it, to close the connection
    http.request(options, responseHandler(res)).end();
};

在nodejs中制作通用响应处理程序的任何方法？

2 个答案: