Unable to export when using gzip compression with OTLP/HTTP and OTLP/PROTO trace exporters

[svetlanabrennan]

Please answer these questions before submitting a bug report.

What version of OpenTelemetry are you using?

"@opentelemetry/api": "^1.0.4",
"@opentelemetry/auto-instrumentations-node": "^0.27.4",
"@opentelemetry/exporter-trace-otlp-proto": "^0.27.0",
"@opentelemetry/resources": "^1.0.1",
"@opentelemetry/sdk-node": "^0.27.0",
"@opentelemetry/semantic-conventions": "^1.0.1",
"@opentelemetry/exporter-trace-otlp-http": "^0.27.0",

What version of Node are you using?

v16.14.0

Please provide the code you used to setup the OpenTelemetry SDK

"use strict";

const { v4: uuidv4 } = require("uuid");
const process = require("process");
const opentelemetry = require("@opentelemetry/sdk-node");
const { getNodeAutoInstrumentations } = require("@opentelemetry/auto-instrumentations-node");
const { Resource } = require("@opentelemetry/resources");
const { SemanticResourceAttributes } = require("@opentelemetry/semantic-conventions");
const { OTLPTraceExporter } = require("@opentelemetry/exporter-trace-otlp-proto");
const api = require("@opentelemetry/api");
const { CompressionAlgorithm } = require('@opentelemetry/exporter-trace-otlp-http')

api.diag.setLogger(
  new api.DiagConsoleLogger(),
  api.DiagLogLevel.DEBUG,
);

const resource = new Resource({
  [SemanticResourceAttributes.SERVICE_NAME]: "OpenTelemetry-Node.JS-Example",
  [SemanticResourceAttributes.SERVICE_INSTANCE_ID]: uuidv4(),
});

const instrumentations = [getNodeAutoInstrumentations()];

const traceExporter = new OTLPTraceExporter({
  compression: CompressionAlgorithm.GZIP,
  url: 'http://localhost:4318/v1/traces'
});

const sdk = new opentelemetry.NodeSDK({
  resource,
  traceExporter,
  instrumentations,
});

sdk
  .start()
  .then(() => console.log("Tracing initialized"))
  .catch((error) => console.log("Error initializing tracing", error));

process.on("SIGTERM", () => {
  sdk
    .shutdown()
    .then(() => console.log("Tracing terminated"))
    .catch((error) => console.log("Error terminating tracing", error))
    .finally(() => process.exit(0));
});

What did you do?

If possible, provide a recipe for reproducing the error.

Can use this example to reproduce the error: https://github.com/newrelic/newrelic-opentelemetry-examples/tree/main/javascript/simple-nodejs-app-http-exp

Just update the endpoint to export to a local collector and add gzip compression to exporter (like shown above).

What did you expect to see?

statusCode: 200

What did you see instead?

Got this error code: stack":"Error: Timeout\n at Timeout._onTimeout......

Additional context

Add any other context about the problem here.

[svetlanabrennan]

Update on this issue:

'Content-Length' header was causing this issue. The length was set before the data was compressed.

Removing Content-Length header solved this issue.

[vmarchaud]

Shouldn't we set the correct length after compression instead ?

[Flarna]

Shouldn't we set the correct length after compression instead ?

this would require to first gzip everything in memory as HTTP headers have to be sent first instead of streaming the data.