Send Rust logs and traces to Bronto via OpenTelemetry

This page covers instrumenting a Rust application with the OpenTelemetry SDK to send logs and traces to Bronto over OTLP/HTTP via a local OTel Collector. Both signals are co-equal: logs are bridged from the log crate — no log statement changes needed — and traces are emitted via a tracer provider.

If you don’t have a Collector and want to export directly from your application to Bronto, see Direct export to Bronto at the bottom of this page.

Prerequisites

Rust 1.70 or later
Cargo
A running OTel Collector configured to forward logs and traces to Bronto — see Connect Open Telemetry to Bronto
OpenTelemetry Rust SDK documentation

Install dependencies

Cargo.toml

# check https://crates.io/crates/opentelemetry for latest version
opentelemetry = { version = "*", features = ["logs"] }
opentelemetry_sdk = { version = "*", features = ["logs", "rt-tokio"] }
opentelemetry-otlp = { version = "*", features = ["logs", "http-proto", "reqwest-client"] }
opentelemetry-appender-log = "*"
opentelemetry-semantic-conventions = "*"
log = "0.4"
tokio = { version = "1", features = ["full"] }

Crate	Purpose
`opentelemetry_sdk`	`SdkLoggerProvider`, processors
`opentelemetry-otlp`	OTLP/HTTP exporter
`opentelemetry-appender-log`	Bridges the `log` crate into OTel
`log`	Standard Rust logging facade

Configure the log bridge

Set up a SdkLoggerProvider with an OTLP exporter and register the OpenTelemetryLogBridge as the global log logger.

otel_logging.rs

use opentelemetry::KeyValue;
use opentelemetry_appender_log::OpenTelemetryLogBridge;
use opentelemetry_otlp::{LogExporter, WithExportConfig};
use opentelemetry_sdk::{
    logs::SdkLoggerProvider,
    resource::Resource,
};
use opentelemetry_semantic_conventions::resource::{
    DEPLOYMENT_ENVIRONMENT_NAME, SERVICE_NAME, SERVICE_NAMESPACE,
};

pub fn configure_otel_logging() -> SdkLoggerProvider {
    let exporter = LogExporter::builder()
        .with_http()
        .with_endpoint("http://localhost:4318/v1/logs")
        .build()
        .expect("failed to build OTLP log exporter");

    let resource = Resource::new(vec![
        KeyValue::new(SERVICE_NAME, "my-service"),
        KeyValue::new(SERVICE_NAMESPACE, "my-team"),
        KeyValue::new(DEPLOYMENT_ENVIRONMENT_NAME, "production"),
    ]);

    let provider = SdkLoggerProvider::builder()
        .with_resource(resource)
        .with_batch_exporter(exporter)
        .build();

    let log_bridge = OpenTelemetryLogBridge::new(&provider);
    log::set_boxed_logger(Box::new(log_bridge)).expect("failed to set logger");
    log::set_max_level(log::LevelFilter::Info);

    provider
}

Configure the OTLP exporter

The with_endpoint call in the snippet above connects to the OTel Collector on localhost:4318. If your Collector runs on a different host or port, update the URL accordingly.

Set resource attributes

Resource attributes are attached to every log record exported from this process. Two attributes drive how Bronto organises incoming logs:

OTel attribute	Bronto concept	Description
`service.name`	Dataset	Groups logs from one service
`service.namespace`	Collection	Groups related services or a team’s services

These are set via Resource::new in the setup above.

Complete example

main.rs

mod otel_logging;

use log::{error, info, warn};

#[tokio::main]
async fn main() {
    let provider = otel_logging::configure_otel_logging();

    info!("Application started");
    warn!("Low disk space, free_gb={}", 2.1);
    error!("Database connection failed: timeout");

    // Flush buffered log records before exit
    provider.shutdown().expect("failed to shut down logger provider");
}

Existing log::info!(), log::warn!(), and log::error!() calls require no changes.

Verify delivery

After running your application, check both signals in Bronto:

Logs: open the Search page and filter by the dataset name you set in service.name — your log records should appear within a few seconds.
Traces: open the Explore Traces page and filter by the same service.name — your spans should appear within a few seconds.

If no logs appear, check:

The OTel Collector is running and reachable at the configured endpoint.
The Collector’s pipeline includes a logs pipeline with an otlp receiver and the Bronto exporter — see Connect Open Telemetry to Bronto.
configure_otel_logging() is called before the first log:: macro.
provider.shutdown() is called before process exit to flush buffered records.

Traces

Middleware instrumentation is available for Actix Web, Axum, Tonic (gRPC), and other popular frameworks via community crates. See the OpenTelemetry Rust registry for available packages.

Install tracing dependencies

Add the tracing feature flags to your existing dependencies:

Cargo.toml

# check https://crates.io/crates/opentelemetry for latest version
opentelemetry = { version = "*", features = ["logs", "trace"] }
opentelemetry_sdk = { version = "*", features = ["logs", "trace", "rt-tokio"] }
opentelemetry-otlp = { version = "*", features = ["logs", "trace", "http-proto", "reqwest-client"] }

Configure the tracer provider

otel_tracing.rs

use opentelemetry::global;
use opentelemetry_otlp::{SpanExporter, WithExportConfig};
use opentelemetry_sdk::{
    resource::Resource,
    trace::SdkTracerProvider,
};

pub fn configure_otel_tracing(resource: Resource) -> SdkTracerProvider {
    let exporter = SpanExporter::builder()
        .with_http()
        .with_endpoint("http://localhost:4318/v1/traces")
        .build()
        .expect("failed to build OTLP span exporter");

    let provider = SdkTracerProvider::builder()
        .with_resource(resource)
        .with_batch_exporter(exporter)
        .build();

    global::set_tracer_provider(provider.clone());
    provider
}

Pass the same Resource used for logging so both signals share service.name and service.namespace.

Creating spans

use opentelemetry::{global, trace::{Tracer, TraceContextExt}};

let tracer = global::tracer("my-service");

tracer.in_span("process-payment", |cx| {
    let span = cx.span();
    span.set_attribute(KeyValue::new("payment.amount", 99.99));
    log::info!("Processing payment");  // trace_id and span_id injected automatically
});

Complete example

main.rs

mod otel_logging;
mod otel_tracing;

use log::{error, info};
use opentelemetry::{global, trace::Tracer};

#[tokio::main]
async fn main() {
    let log_provider = otel_logging::configure_otel_logging();
    let trace_provider = otel_tracing::configure_otel_tracing(
        // pass the same resource — create it once and share it
        opentelemetry_sdk::resource::Resource::new(vec![
            opentelemetry::KeyValue::new("service.name", "my-service"),
            opentelemetry::KeyValue::new("service.namespace", "my-team"),
        ])
    );

    let tracer = global::tracer("my-service");
    tracer.in_span("handle-request", |_cx| {
        info!("Handling request");  // trace_id + span_id attached automatically
    });

    log_provider.shutdown().expect("failed to shut down log provider");
    trace_provider.shutdown().expect("failed to shut down trace provider");
}

GenAI semantic conventions

If your application calls an LLM, OpenTelemetry defines GenAI semantic conventions. There is no first-party GenAI auto-instrumentation package for Rust yet — set the attributes yourself around each LLM call:

This page was verified on July 17, 2026. GenAI libraries and semantic conventions are evolving rapidly, so package configuration and emitted attributes can change between releases. Keep your instrumentation current and verify the fields emitted by the version you deploy.

use opentelemetry::{global, trace::Tracer, KeyValue};

let tracer = global::tracer("my-service");

tracer.in_span("chat gpt-4o-mini", |cx| {
    let span = cx.span();
    span.set_attribute(KeyValue::new("gen_ai.provider.name", "openai"));
    span.set_attribute(KeyValue::new("gen_ai.request.model", "gpt-4o-mini"));
    span.set_attribute(KeyValue::new("gen_ai.usage.input_tokens", 33));
    span.set_attribute(KeyValue::new("gen_ai.usage.output_tokens", 74));
});

Message content (gen_ai.input.messages / gen_ai.output.messages) is opt-in by convention in languages with auto-instrumentation, off by default. Since you’re setting attributes by hand here, apply the same discipline — gate prompt/response content behind your own config flag rather than always sending it.

See LLM Observability for the full recommended attribute set and how to search and aggregate GenAI fields in Bronto.

Direct export to Bronto

If you are not using an OTel Collector, export directly to Bronto by replacing the exporter configurations with the Bronto OTLP endpoints and your API key:

use std::collections::HashMap;

let mut headers = HashMap::new();
headers.insert("x-bronto-api-key".to_string(), "<YOUR_API_KEY>".to_string());

let log_exporter = LogExporter::builder()
    .with_http()
    .with_endpoint("https://ingestion.eu.bronto.io/v1/logs") // or ingestion.us.bronto.io
    .with_headers(headers.clone())
    .build()
    .expect("failed to build log exporter");

let span_exporter = SpanExporter::builder()
    .with_http()
    .with_endpoint("https://ingestion.eu.bronto.io/v1/traces") // or ingestion.us.bronto.io
    .with_headers(headers)
    .build()
    .expect("failed to build span exporter");

Region	Logs endpoint	Traces endpoint
EU	`https://ingestion.eu.bronto.io/v1/logs`	`https://ingestion.eu.bronto.io/v1/traces`
US	`https://ingestion.us.bronto.io/v1/logs`	`https://ingestion.us.bronto.io/v1/traces`

See API Keys for how to create a key with ingestion permissions. No other changes to the rest of the setup are required.

Overview

Ingest with agents

Ingest from AWS

Ingest from Azure

Ingest from CDN and edge

Ingest from apps and platforms

Ingest from infrastructure and databases

Ingest OpenTelemetry data

Send Rust logs and traces to Bronto via OpenTelemetry

Prerequisites

Install dependencies

Configure the log bridge

Configure the OTLP exporter

Set resource attributes

Complete example

Verify delivery

Traces

Install tracing dependencies

Configure the tracer provider

Creating spans

Complete example

GenAI semantic conventions

Direct export to Bronto

​Prerequisites

​Install dependencies

​Configure the log bridge

​Configure the OTLP exporter

​Set resource attributes

​Complete example

​Verify delivery

​Traces

​Install tracing dependencies

​Configure the tracer provider

​Creating spans

​Complete example

​GenAI semantic conventions

​Direct export to Bronto

Prerequisites

Install dependencies

Configure the log bridge

Configure the OTLP exporter

Set resource attributes

Complete example

Verify delivery

Traces

Install tracing dependencies

Configure the tracer provider

Creating spans

Complete example

GenAI semantic conventions

Direct export to Bronto