Node.js HTTP response streams
The response object from a HTTP request is an instance of readable stream. Therefore, you would collect the data with the data
event, then use it when the end
event fires.
var http = require('http');
var body = '';
http.get(url, function(res) {
res.on('data', function(chunk) {
body += chunk;
});
res.on('end', function() {
// all data has been downloaded
});
});
The readable.pipe(dest)
would basically do the same thing, if body
in the example above were a writable stream.
Nowadays the recommended way of piping is using the pipeline function. It is supposed to protect you from memory leaks.
const { createReadStream} = require('fs');
const { pipeline } = require('stream')
const { createServer, get } = require('http')
const errorHandler = (err) => err && console.log(err.message);
const server = createServer((_, response) => {
pipeline(createReadStream(__filename), response, errorHandler)
response.writeHead(200);
}).listen(8080);
get('http://localhost:8080', (response) => {
pipeline(response, process.stdout, errorHandler);
response.on('close', () => server.close())
});
Another way of doing it that has more control would be to use async iterator
async function handler(response){
let body = ''
for await (const chunk of response) {
let text = chunk.toString()
console.log(text)
body += text
}
console.log(body.length)
server.close()
}
get('http://localhost:8080', (response) => handler(response).catch(console.warn));