Is your feature request related to a problem? Please describe.

We've been experiencing failures when exporting data from our Node.js SDK to the OpenTelemetry Collector through gRPC. After Collector restarts or deployments, the connections become unhealthy in environments with load balancers or network configurations that terminate idle connections.

To address this issue, we've tuned the settings for gRPC keepalive and reconnections in our Go SDK, and we're seeing good results so far. However, there's no equivalent capability in the Node.js OTLP gRPC exporters, since the @grpc/grpc-js channel options aren't exposed.

I've found an issue that dates back to 2023, which was automatically closed by the stale bot: #4024.

Describe the solution you'd like

The GrpcExporterTransport in @opentelemetry/otlp-grpc-exporter-base currently hardcodes only compression and user-agent options:

The ChannelOptions interface in @grpc/grpc-js not only support the settings we need, but some other useful settings as well:

https://github.com/grpc/grpc-node/blob/164d14f28261ad1fbbc99d076fe850dad018b2bb/packages/grpc-js/src/channel-options.ts#L28-L30

• grpc.keepalive_time_ms - interval between pings
• grpc.keepalive_timeout_ms - timeout waiting for ping acknowledgement
• grpc.keepalive_permit_without_calls - send pings even without active RPCs
• grpc.initial_reconnect_backoff_ms / grpc.max_reconnect_backoff_ms - reconnection timing

A possible solution would be adding a channelOptions parameter to OTLPGRPCExporterConfigNode:

export interface OTLPGRPCExporterConfigNode extends OTLPExporterConfigBase {
  credentials?: ChannelCredentials;
  metadata?: Metadata;
  compression?: CompressionAlgorithm;
  userAgent?: string;
  channelOptions?: Partial<ChannelOptions>;
}

Example usage:

import { OTLPTraceExporter } from '@opentelemetry/exporter-trace-otlp-grpc';

const exporter = new OTLPTraceExporter({
    url: 'otel-collector.example.com:4317',
    channelOptions: {
        'grpc.keepalive_time_ms': 50000,
        'grpc.keepalive_timeout_ms': 60000,
        'grpc.keepalive_permit_without_calls': 1,
        'grpc.initial_reconnect_backoff_ms': 5000,
        'grpc.max_reconnect_backoff_ms': 5000,
    },
});

Describe alternatives you've considered

1. Switching to HTTP exporter, but it loses the gRPC benefits.
2. Implementing a custom GrpcExporterTransport, but requires tracking upstream changes.

Additional context

• Go SDK parity: The Go OTLP exporter exposes WithDialOption() for full gRPC configuration control. Should Node.js have an equivalent capability?
• Once this issue has been discussed and considering we have a valid proposal, I'm willing to submit a PR implementing this feature.

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