Why pure Python?

The distribution ships its own OTLP exporters built on pure-Python protobuf message classes (dash0-opentelemetry-pyproto). These exporters have no dependency on google.protobuf or grpcio, which are C extension packages that require binary compatibility with the target application.

Injecting a package with native dependencies into an arbitrary process risks ABI conflicts (different versions of the shared library) or version conflicts (the application already uses a different version of google.protobuf). The pure-Python exporters eliminate that class of problem.

Available exporters

OTLP/HTTP (default)

Exporter name: otlp_proto_http Package: dash0-opentelemetry-exporter-otlp-pyproto-http

Selected by default for all three signals (traces, metrics, logs). Sends protobuf-encoded OTLP over HTTP/1.1. Compatible with any OTLP-capable collector, including the Dash0 ingress.

OTLP/gRPC

Exporter name: otlp_proto_grpc Package: dash0-opentelemetry-exporter-otlp-pyproto-grpc

Available as an alternative to OTLP/HTTP. Uses the same pure-Python protobuf implementation. Activate it by setting the protocol:

bash

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export OTEL_EXPORTER_OTLP_PROTOCOL=grpc

Or for a specific signal only:

bash

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export OTEL_EXPORTER_OTLP_TRACES_PROTOCOL=grpc

Drop-in replacement for upstream exporters

The pyproto exporters occupy the same import namespaces and register under the same entry-point names (otlp_proto_http, otlp_proto_grpc) as the upstream opentelemetry-exporter-otlp-proto-http and opentelemetry-exporter-otlp-proto-grpc packages.

Because the distribution depends on the pyproto packages rather than the upstream ones, the standard exporter names resolve to the pure-Python implementations automatically. No configuration change is required; existing OTEL_EXPORTER_OTLP_* settings continue to work.

Once the upstream OpenTelemetry project publishes official pure-Python exporter releases, the distribution will depend on those and deprecate the vendored copies.

Protocol selection

The protocol is selected per signal using the following priority order:

OTEL_EXPORTER_OTLP_<SIGNAL>_PROTOCOL (e.g., OTEL_EXPORTER_OTLP_TRACES_PROTOCOL)
OTEL_EXPORTER_OTLP_PROTOCOL
Default: http/protobuf

Intelligent endpoint rewriting

When a signal uses a different protocol than the shared base URL's conventional port implies, the distribution automatically derives the correct per-signal endpoint.

Example: DASH0_OTEL_COLLECTOR_BASE_URL=http://collector:4318 (the HTTP port) and OTEL_EXPORTER_OTLP_TRACES_PROTOCOL=grpc. The distribution rewrites the traces endpoint to http://collector:4317 (the gRPC port) so traces are sent to the right listener.

Rules:

If the base URL port is the gRPC default (4317) and a signal uses HTTP, the signal's endpoint is rewritten to port 4318 with the /v1/<signal> path appended.
If the base URL port is the HTTP default (4318) and a signal uses gRPC, the signal's endpoint is rewritten to port 4317.
Custom ports and explicitly set per-signal endpoints are never rewritten.

OTLP Exporters