matrix-public-archive/server/tracing/tracing.js

108 lines
3.8 KiB
JavaScript

'use strict';
const assert = require('assert');
const { registerInstrumentations } = require('@opentelemetry/instrumentation');
const { getNodeAutoInstrumentations } = require('@opentelemetry/auto-instrumentations-node');
const { diag, DiagConsoleLogger, DiagLogLevel } = require('@opentelemetry/api');
const { JaegerExporter } = require('@opentelemetry/exporter-jaeger');
const {
BasicTracerProvider,
// ConsoleSpanExporter,
// SimpleSpanProcessor,
BatchSpanProcessor,
} = require('@opentelemetry/sdk-trace-base');
const { AsyncLocalStorageContextManager } = require('@opentelemetry/context-async-hooks');
const { OTTracePropagator } = require('@opentelemetry/propagator-ot-trace');
const { Resource } = require('@opentelemetry/resources');
const { SemanticResourceAttributes } = require('@opentelemetry/semantic-conventions');
const CaptureSpanProcessor = require('./capture-span-processor');
const config = require('../lib/config');
const jaegerTracesEndpoint = config.get('jaegerTracesEndpoint');
const packageInfo = require('../../package.json');
assert(packageInfo.name);
// (Diagnostics) For troubleshooting, set the log level to DiagLogLevel.DEBUG.
//
diag.setLogger(new DiagConsoleLogger(), DiagLogLevel.INFO);
const provider = new BasicTracerProvider({
resource: new Resource({
[SemanticResourceAttributes.SERVICE_NAME]: packageInfo.name,
}),
});
// Export spans to console (useful for debugging).
// provider.addSpanProcessor(new SimpleSpanProcessor(new ConsoleSpanExporter()));
// Export spans to Jaeger
let isExportingToJaeger = false;
if (jaegerTracesEndpoint) {
const exporter = new JaegerExporter({
tags: [],
endpoint: jaegerTracesEndpoint,
});
// Use this for immediate span submission
//provider.addSpanProcessor(new SimpleSpanProcessor(exporter));
// Otherwise, we should just use the more performant batched processor
provider.addSpanProcessor(new BatchSpanProcessor(exporter));
isExportingToJaeger = true;
}
const captureSpanProcessor = new CaptureSpanProcessor();
provider.addSpanProcessor(captureSpanProcessor);
function startTracing() {
if (!isExportingToJaeger) {
console.warn(
`⚠ Tracing was started but \`jaegerTracesEndpoint\` was not configured so we are not exporting anything.`
);
}
provider.register({
contextManager: new AsyncLocalStorageContextManager(),
propagator: new OTTracePropagator(),
});
registerInstrumentations({
instrumentations: [
getNodeAutoInstrumentations({
'@opentelemetry/instrumentation-http': {
// Docs:
// https://github.com/open-telemetry/opentelemetry-js/tree/51afd54bd63e46d5d530266761144c7be2f6b3a7/experimental/packages/opentelemetry-instrumentation-http#http-instrumentation-options
//
// This is the place to ignore root level spans for Express routes. My
// first guess would be in `ignoreLayers` in
// `@opentelemetry/instrumentation-express` but that's not the case, see
// https://github.com/open-telemetry/opentelemetry-js-contrib/issues/1034#issuecomment-1158435392
ignoreIncomingRequestHook: (req) => {
// Ignore spans from static assets.
//
// FIXME: Ideally, all of the assets would all be served under
// `/static/` so we could ignore that way instead. In Hydrogen, this
// is tracked by https://github.com/vector-im/hydrogen-web/issues/757
const isStaticAsset = !!req.url.match(/\.(css|js|svg|woff2)(\?.*?)?$/);
return isStaticAsset;
},
},
}),
],
});
process.on('SIGTERM', () => {
provider
.shutdown()
.then(() => console.log('Tracing terminated'))
.catch((error) => console.log('Error terminating tracing', error))
.finally(() => process.exit(0));
});
}
module.exports = {
startTracing,
provider,
captureSpanProcessor,
};