A sentence in response was found in the process of reading node API

The response inherits from Stream, and additionally implements the following:

This class implements (rather than inherits from) the writable stream interface. It is an [EventEmitter] with the following events 🙂

  1. Fs.createreadstream (filePath).pipe(response);

    • CreateReadStrem is returned:

      See readable Streams.
    • A response is of course a response
    • Pipe is the connection of two data streams.

  2. Does that output the data stream?

    • We know that WriteStream (a writable stream is an abstraction of the destination to which data is to be written.)
    • All examples of Writable streams (including the fs write-in stream) implement the interface defined by the stream.Writable class.
    • That is, you can output streams of data
    • And the preface mentioned that Response also implements a writable stream interface
    • Fs.createreadstream then concatenates the response with response and is ready to output

  3. Here’s a quick example

    const http = require('http');
const fs = require('fs');
const url = require('url');
const path =require('path');
// Get the root directory from the command line argument. The default is the current directory:
var root = path.resolve(process.argv[2] | |'. ');

console.log('Static root dir: ' + root);

// Create server:
var server = http.createServer(function (request, response) {
    // Get the path of the URL, like '/ CSS /bootstrap.css':
    var pathname = url.parse(request.url).pathname;
    / / get the corresponding local file path, like '/ SRV/WWW/CSS/bootstrap CSS' :
    var filepath = path.join(root, pathname);
    Stat () to check whether a file exists.Stats is the fs.stats object, which provides information about a file
    fs.stat(filepath, function (err, stats) {	
        if(! err && stats.isFile()) {Stats.isfile () returns true if the fs.stats object represents a normal file
            // There is no error and the file exists:
            console.log('200' + request.url);
            // Send 200 responses:
            response.writeHead(200);
            // Redirect the file stream to response:Fs. CreateReadStream (filepath.) pipe (response); }else {
            // Error or file does not exist:
            console.log('404' + request.url);
            // Send a 404 response:
            response.writeHead(404);
            response.end('404 Not Found'); }}); }); server.listen(8080);
Copy the code