OTLP Environment variables do not match specification #971
Description
Currently, OTLP environment variables (OTEL_EXPORTER_OTLP_GRPC_ENDPOINT) does not match the specification.
Copied relevant sections:
Configuration Options
The following configuration options MUST be available to configure the OTLP exporter. Each configuration option MUST be overridable by a signal specific option.
| Configuration Option | Description | Default | Env variable |
|---|---|---|---|
| Endpoint | Target to which the exporter is going to send spans or metrics. The endpoint MUST be a valid URL with scheme (http or https) and host, and MAY contain a port and path. A scheme of https indicates a secure connection. When using OTEL_EXPORTER_ENDPOINT with OTLP/HTTP, exporters SHOULD follow the collector convention of appending the version and signal to the path (e.g. v1/traces or v1/metrics). The per-signal endpoint configuration options take precedence and can be used to override this behavior. See the [OTLP Specification][otlphttp-req] for more details. |
https://localhost:4317 |
OTEL_EXPORTER_OTLP_ENDPOINT OTEL_EXPORTER_OTLP_TRACES_ENDPOINT OTEL_EXPORTER_OTLP_METRICS_ENDPOINT |
| Certificate File | Path to certificate file for TLS credentials of gRPC client. Should only be used for a secure connection. | n/a | OTEL_EXPORTER_OTLP_CERTIFICATE OTEL_EXPORTER_OTLP_TRACES_CERTIFICATE OTEL_EXPORTER_OTLP_METRICS_CERTIFICATE |
| Headers | Key-value pairs to be used as headers associated with gRPC or HTTP requests. See Specifying headers for more details. | n/a | OTEL_EXPORTER_OTLP_HEADERS OTEL_EXPORTER_OTLP_TRACES_HEADERS OTEL_EXPORTER_OTLP_METRICS_HEADERS |
| Compression | Compression key for supported compression types. Supported compression: gzip |
No value | OTEL_EXPORTER_OTLP_COMPRESSION OTEL_EXPORTER_OTLP_TRACES_COMPRESSION OTEL_EXPORTER_OTLP_METRICS_COMPRESSION |
| Timeout | Max waiting time for the backend to process each spans or metrics batch. | 10s | OTEL_EXPORTER_OTLP_TIMEOUT OTEL_EXPORTER_OTLP_TRACES_TIMEOUT OTEL_EXPORTER_OTLP_METRICS_TIMEOUT |
Supported values for OTEL_EXPORTER_OTLP_*COMPRESSION options:
- If the value is missing, then compression is disabled.
gzipis the only specified compression method for now. Other options MAY be supported by language SDKs and should be documented for each particular language.
Example 1
The following configuration sends all signals to the same collector:
export OTEL_EXPORTER_OTLP_ENDPOINT=http://collector:4317Example 2
Traces and metrics are sent to different collectors:
export OTEL_EXPORTER_OTLP_TRACES_ENDPOINT=http://collector:4317
export OTEL_EXPORTER_OTLP_METRICS_ENDPOINT=https://collector.example.com/v1/metricsSpecify Protocol
Currently, OTLP has more than one transport protocol it can support, e.g.
grpc, http/json, http/protobuf. As of 1.0 of the specification, there
is no specified default, or configuration via environment variables. We
reserve the following environment variables for configuration of protocols in
the future:
OTEL_EXPORTER_OTLP_PROTOCOLOTEL_EXPORTER_OTLP_TRACES_PROTOCOLOTEL_EXPORTER_OTLP_METRICS_PROTOCOL
SDKs have an unspecified default, if no configuration is provided.
Specifying headers via environment variables
The OTEL_EXPORTER_OTLP_HEADERS, OTEL_EXPORTER_OTLP_TRACES_HEADERS, OTEL_EXPORTER_OTLP_METRICS_HEADERS environment variables will contain a list of key value pairs, and these are expected to be represented in a format matching to the W3C Correlation-Context, except that additional semi-colon delimited metadata is not supported, i.e.: key1=value1,key2=value2. All attribute values MUST be considered strings.