Node.js Http2ServerResponse.headersSent用法及代码示例

Http2ServerResponse.headersSent 是 http2 模块中 Http2ServerResponse 类的内置应用程序编程接口，用于检查是否发送了标头。

用法:

response.headersSent

参数：此属性不接受任何参数作为参数。

返回值:当且仅当发送了标头时，此属性返回 true，否则返回 false。

如何生成私钥和公共证书？

1.文件名：私钥

打开记事本和copy-paste下面的项并将文件另存为private-key.pem

2.文件名：公开证书

打开记事本和copy-paste下面的项并将文件另存为public-cert.pem

示例1：Filename：index.js

Javascript


// Node.js program to demonstrate the
// Http2ServerResponse.headersSent
const http2 = require('http2');
const fs = require('fs');
  
// Private key and public certificate for access
const options = {
  key:fs.readFileSync('private-key.pem'),
  cert:fs.readFileSync('public-cert.pem'),
};
  
// Request and response handler
const http2Handlers = (request, response) => {
    // Setting new header
    response.setHeader(
      'Content-Type', 
      'hello world; charset=utf-8'
    );
  
    // Checking if the header is sent or not
    // by using headersSent method
    const value = response.headersSent
  
    // Display the header
    if(value) {
        console.log("header is sent")
    } else {
        console.log("header is not sent")
    }
};
  
// Creating and initializing server
// by using http2.createServer() method
const server = http2.createServer(options, http2Handlers);
  
server.on('stream', (stream, requestheader) => {
    stream.write('hello ');
  
    // Getting all information of this http2stream
    // object by using state method
    const status = stream.state;
  
    stream.end("priority weight:" + status.weight);
  
    // Stopping the server
    // by using the close() method
    server.close(() => {
        console.log("server destroyed");
    })
});
  
server.listen(8000);
  
// Creating and initializing client
// by using tls.connect() method
const client = http2.connect('http://localhost:8000');
  
const req = client.request({ 
  ':method':'GET', ':path':'/'});
  
req.on('response', (responsesocket) => {
  console.log("status:" + responsesocket[":status"]);
});
  
req.on('data', (data) => {
  console.log('Received:%s ',
  data.toString().replace(/(\n)/gm,""));
});
  
req.on('end', () => {
  client.close(() => {
    console.log("client destroyed");
  })
});

使用以下命令运行index.js文件：

node index.js

输出：

header is not sent
status:200
Received:hello
Received:priority weight:16
client destroyed
server destroyed

示例2：Filename：index.js

Javascript


// Node.js program to demonstrate the
// Http2ServerResponse.headersSent method
const http2 = require('http2');
const fs = require('fs');
  
// Private key and public certificate for access
const options = {
  key:fs.readFileSync('private-key.pem'),
  cert:fs.readFileSync('public-cert.pem'),
};
  
// Request and response handler
const http2Handlers = (request, response) => {
    // Setting new header
    response.setHeader('Foo', 'bar');
    response.setHeader(
      'Set-Cookie', ['foo=bar', 'bar=baz']);
  
    // Sending the header
    response.end("hello");
  
    // Checking if the header is sent or not
    // by using headersSent method
    const value = response.headersSent
  
    // Display the header
    if(value) console.log("header is sent")
    else console.log("header is not sent")
};
  
// Creating and initializing server
// by using http2.createServer() method
const server = http2.createServer(options, http2Handlers);
  
server.on('stream', (stream, requestHeaders) => {
  
    // Getting all information of this http2stream
    // object by using state method
    const status = stream.state;
  
    stream.end("The sum weight of all Http2Stream:"
        + status.sumDependencyWeight);
  
    // Stopping the server
    // by using the close() method
    server.close(() => {
        console.log("server destroyed");
    })
});
  
server.listen(8000);
  
// Creating and initializing client
// by using tls.connect() method
const client = http2.connect('http://localhost:8000');
  
const req = client.request({ ':method':'GET',
':path':'/www.geeksforgeeks.org' });
  
req.on('data', (data) => {
  console.log('Received:%s ',
  data.toString().replace(/(\n)/gm,""));
});
  
req.on('end', () => {
  client.close(() => {
    console.log("client destroyed");
  })
});

使用以下命令运行index.js文件：

node index.js

输出：

header is sent
Received:hello
client destroyed
server destroyed

参考：https://nodejs.org/dist/latest-v12.x/docs/api/http2.html#http2_response_headerssent

相关用法

注：本文由纯净天空筛选整理自RohitPrasad3大神的英文原创作品 Node.js Http2ServerResponse.headersSent Property。非经特殊声明，原始代码版权归原作者所有，本译文未经允许或授权，请勿转载或复制。