opentelemetry-js/examples/http/server.js

57 lines
1.6 KiB
JavaScript

'use strict';
const opentelemetry = require('@opentelemetry/core');
const config = require('./setup');
/**
* The trace instance needs to be initialized first, if you want to enable
* automatic tracing for built-in plugins (HTTP in this case).
*/
config.setupTracerAndExporters('http-server-service');
const http = require('http');
const tracer = opentelemetry.getTracer('example-http-server');
/** Starts a HTTP server that receives requests on sample server port. */
function startServer (port) {
// Creates a server
const server = http.createServer(handleRequest);
// Starts the server
server.listen(port, err => {
if (err) {
throw err;
}
console.log(`Node HTTP listening on ${port}`);
});
}
/** A function which handles requests and send response. */
function handleRequest (request, response) {
const currentSpan = tracer.getCurrentSpan();
// display traceid in the terminal
console.log(`traceid: ${currentSpan.context().traceId}`);
const span = tracer.startSpan('handleRequest', {
parent: currentSpan,
kind: 1, // server
attributes: { key:'value' }
});
// Annotate our span to capture metadata about the operation
span.addEvent('invoking handleRequest');
try {
let body = [];
request.on('error', err => console.log(err));
request.on('data', chunk => body.push(chunk));
request.on('end', () => {
// deliberately sleeping to mock some action.
setTimeout(() => {
span.end();
response.end('Hello World!');
}, 2000);
});
} catch (err) {
console.log(err);
span.end();
}
}
startServer(8080);