auto-instrumentation with winston doesn't seem to report logs to open collector

[li-dennis]

Hi,

I'm trying to setup opentelemetry to automatically instrument my project, and while traces work, I cannot seem to get the winston instrumentation to report logs back to opentelemetry collector.

both via the CLI approach of

export OTEL_TRACES_EXPORTER="otlp"
export OTEL_EXPORTER_OTLP_ENDPOINT="http://otelcol:4317"
export OTEL_SERVICE_NAME="your-service-name"
export NODE_OPTIONS="--require @opentelemetry/auto-instrumentations-node/register"
node app.js

and the SDK approach of

import { getNodeAutoInstrumentations } from "@opentelemetry/auto-instrumentations-node";
import { OTLPTraceExporter } from "@opentelemetry/exporter-trace-otlp-grpc";
import { Resource } from "@opentelemetry/resources";
import { NodeSDK } from "@opentelemetry/sdk-node";

import { diag, DiagConsoleLogger, DiagLogLevel } from "@opentelemetry/api";
import { SEMRESATTRS_SERVICE_NAME } from "@opentelemetry/semantic-conventions";
import { WinstonInstrumentation } from "@opentelemetry/instrumentation-winston";

diag.setLogger(new DiagConsoleLogger(), DiagLogLevel.DEBUG);
const traceExporter = new OTLPTraceExporter();

const sdk = new NodeSDK({
    resource: new Resource({
        [SEMRESATTRS_SERVICE_NAME]: process.env.OTEL_SERVICE_NAME
    }),
    traceExporter,
    instrumentations: [
        getNodeAutoInstrumentations({
            "@opentelemetry/instrumentation-fs": { enabled: false },
            "@opentelemetry/instrumentation-winston": { enabled: true }
        }),
        new WinstonInstrumentation({
            logHook: (_span, record) => {
                record["resource.service.name"] = process.env.OTEL_SERVICE_NAME;
            }
        })
    ]
});

sdk.start();

Later on, I have this snippet:

const winstonLogger = winston.createLogger({
    level: "info",
    format: winston.format.json(),
    transports: [new winston.transports.Console({})]
});

winstonLogger.info("Hello, Winston!");

My Logs
I've opted for the first approach since it seems like the second approach requires the instrumentation to initialize prior to winston being imported (?), but in either case, I run into the same issue in both. I don't see my messages even getting logged when I set OTEL_LOG_LEVEL=debug

My console logs

HostDetectorSync found resource. Resource {
...
}
...
@opentelemetry/instrumentation-winston Applying patch for winston@3.13.0
{"level":"info","message":"Hello, Winston!"}
...

Winston is getting patched, and my message of "Hello, Winston!" is getting sent to my console, but not to my opentelemetry-collector.

In contrast, with the automatic instrumentation in python, I can see my logs getting reported to opencollector (and opensearch) just fine. I can't tell if I'm doing something wrong here. I can also manually instrument it successfully by adding a opentelemetry log handler to my node logger, but I'd prefer not to do that, and instead just let the autoinstrumentation work.

• This only affects the JavaScript OpenTelemetry library
• This may affect other libraries, but I would like to get opinions here first

[DivyaNayaka]

Even I have the same question. So, I went through the code base, and based on this, I will ask if someone can answer or the contributors @hectorhdzg

After setting up Winston auto instrumentation (incl. Winston transport), do we need to configure a loggerProvider from Logs SDK to forward those to the otel-collector?

[mhennoch]

I think you need to specify logRecordProcessor in your configuration for provider to be registered.

[architgarg95]

Even after providing the logRecordProcessor it doesn't send the logs to otel collector, right now I have patched the winston logger to emit logs to otel-collector every time something gets logged. It would be better if the logs could get exported by providing the logRecordProcessor

[mhennoch]

If you configure it to use console exporter does that work? Can you share your final configuration?

[DivyaNayaka]

For me, Winston's auto instrumentation is not working and needs fixing.

What worked for me was the execution order below.

• Set a global logger provider that will export the logs to the Otel collector
• Register Winston instrumentation as auto instrumentation is not registering it
• Create Winston logger with console output