Stream application/json POST request - node.js

Question

I have working code to buffer a .json file and then POST that data to a server.
fs.readFile(filePath, 'utf-8', function (err, buf) {
if(err){
reject(err);
}
else{
const req = http.request({
method: 'POST',
host: 'localhost',
path: '/event',
port: '4031',
headers: {
'Content-Type': 'application/json',
'Content-Length': buf.length
}
});
req.on('error', reject);
var data = '';
req.on('response', function (res) {
res.setEncoding('utf8');
res.on('data', function ($data) {
data += $data
});
res.on('end', function () {
data = JSON.parse(data);
console.log('data from SC:', data);
//call fn on data and if it passes we are good
resolve();
});
});
// write data to request body
req.write(buf);
req.end();
}
});
what I would like to do instead is to avoid buffering it, and just use fs.createReadStream, something like so:
fs.createReadStream(filePath, 'utf-8', function (err, strm) {
if(err){
reject(err);
}
else{
const req = http.request({
method: 'POST',
host: 'localhost',
path: '/event',
port: '4031',
headers: {
'Content-Type': 'application/json',
// 'Content-Length': buf.length
}
});
req.on('error', reject);
var data = '';
req.on('response', function (res) {
res.setEncoding('utf8');
res.on('data', function ($data) {
data += $data
});
res.on('end', function () {
data = JSON.parse(data);
console.log('data from SC:', data);
//call fn on data and if it passes we are good
resolve();
});
});
// write data to request body
req.write(strm);
req.end();
}
});
but that doesn't quite work? Is it possible to do this?

Answer 1

This seems to work, but not sure if it's 100% correct
const strm = fs.createReadStream(filePath);
const req = http.request({
method: 'POST',
host: 'localhost',
path: '/event',
port: '4031',
headers: {
'Content-Type': 'application/json',
}
});
req.on('error', reject);
var data = '';
req.on('response', function (res) {
res.setEncoding('utf8');
res.on('data', function ($data) {
data += $data
});
res.on('end', function () {
data = JSON.parse(data);
resolve();
});
});
// write data to request body
strm.pipe(req);