🐛 Bug Report: gRPC exporter fails with StatusCode.UNAVAILABLE when connecting to insecure OTLP collector

[boscoraju-snyk]

Which component is this bug for?

Traceloop SDK

📜 Description

When using the Traceloop SDK with a gRPC endpoint (no http:// prefix), the exporter fails with StatusCode.UNAVAILABLE even when:

1. TCP connectivity to the endpoint works
2. The OpenTelemetry Collector is configured to accept insecure gRPC connections

Root Cause

In traceloop/sdk/tracing/tracing.py, the init_spans_exporter function creates a GRPCExporter without setting insecure=True:

def init_spans_exporter(api_endpoint: str, headers: Dict[str, str]) -> SpanExporter:
    if "http" in api_endpoint.lower() or "https" in api_endpoint.lower():
        return HTTPExporter(endpoint=f"{api_endpoint}/v1/traces", headers=headers)
    else:
        return GRPCExporter(endpoint=f"{api_endpoint}", headers=headers)  # Missing insecure=True. The OpenTelemetry `OTLPSpanExporter` (gRPC) defaults `insecure=False`, which means it attempts a TLS connection. When the collector accepts insecure connections, the TLS handshake fails.

Environment

• Traceloop SDK version: 0.49.1
• Python version: 3.12
• OpenTelemetry Collector configured with:

  receivers:
    otlp:
      protocols:
        grpc:
          endpoint: 0.0.0.0:4317  # No TLS configured

👟 Reproduction steps

1. Configure Traceloop with a gRPC endpoint (no http/https prefix):

Traceloop.init(app_name="myapp",  api_endpoint="otelcol.example.com:4317")

2. Run the application

3. Observe error:

Failed to export traces to otelcol.example.com:4317, error code: StatusCode.UNAVAILABLE

👍 Expected behavior

The SDK should successfully connect to collectors that accept insecure gRPC connections.

👎 Actual Behavior with Screenshots

{"level": "error", "message": "Failed to export traces to otelcol.example.svc.cluster.local:4317, error code: StatusCode.UNAVAILABLE", "time": "2025-11-27T16:10:04.348Z", "caller": "/app/.venv/lib/python3.12/site-packages/opentelemetry/exporter/otlp/proto/grpc/exporter.py:416"}

{"level": "error", "message": "Failed to export traces to otelcol.example.svc.cluster.local:4317, error code: StatusCode.UNAVAILABLE", "time": "2025-11-27T16:10:06.299Z", "caller": "/app/.venv/lib/python3.12/site-packages/opentelemetry/exporter/otlp/proto/grpc/exporter.py:416"}

{"level": "warning", "message": "Transient error StatusCode.UNAVAILABLE encountered while exporting traces to otelcol.example.svc.cluster.local:4317, retrying in 0.80s.", "time": "2025-11-27T16:10:07.077Z", "caller": "/app/.venv/lib/python3.12/site-packages/opentelemetry/exporter/otlp/proto/grpc/exporter.py:424"}

🤖 Python Version

python3.12

📃 Provide any additional context for the Bug.

Support standard gRPC URL schemes like other gRPC clients:

Scheme	Protocol	TLS
grpc://	gRPC	❌ Insecure
grpcs://	gRPC	✅ Secure (TLS)

def init_spans_exporter(api_endpoint: str, headers: Dict[str, str]) -> SpanExporter:
    endpoint_lower = api_endpoint.lower()
    
    if endpoint_lower.startswith("http://") or endpoint_lower.startswith("https://"):
        return HTTPExporter(endpoint=f"{api_endpoint}/v1/traces", headers=headers)
    elif endpoint_lower.startswith("grpc://"):
        # Insecure gRPC
        clean_endpoint = api_endpoint[7:]  # Remove "grpc://"
        return GRPCExporter(endpoint=clean_endpoint, headers=headers, insecure=True)
    elif endpoint_lower.startswith("grpcs://"):
        # Secure gRPC (TLS)
        clean_endpoint = api_endpoint[8:]  # Remove "grpcs://"
        return GRPCExporter(endpoint=clean_endpoint, headers=headers, insecure=False)
    else:
        # No scheme: default to insecure gRPC for backward compatibility
        return GRPCExporter(endpoint=api_endpoint, headers=headers, insecure=True)

This follows the standard convention used by gRPC clients across languages:

• grpc://host:port → insecure connection
• grpcs://host:port → secure connection (TLS)

👀 Have you spent some time to check if this bug has been raised before?

• I checked and didn't find similar issue

Are you willing to submit PR?

Yes I am willing to submit a PR!