Rust Tracing

Learn about the Rust Tracing integration and how to get performance data for Rust native extensions.

RustTracingIntegration acts as a bridge between the Sentry Python SDK and Rust's tracing framework. With this integration, traces that begin in Python can extend into Rust seamlessly.

RustTracingIntegration requires setup in both Python and Rust to work.

In your Rust native extension, you'll need three crates as dependencies in Cargo.toml:

In your Python project, you'll need to install the Sentry SDK from PyPI.

Copied
pip install --upgrade sentry-sdk

As with installing, configuring RustTracingIntegration requires some work in both Python and Rust.

In your Rust native extension, you need to expose a way for RustTracingIntegration to subscribe to tracing updates. A simple setup may look like this:

Copied
#[pyfunction]
pub fn initialize_tracing(py_impl: Bound<'_, PyAny>) {
    tracing_subscriber::registry()
        .with(pyo3_python_tracing_subscriber::PythonCallbackLayerBridge::new(py_impl))
        .init();
}

#[pymodule]
fn my_rust_extension(m: &Bound<'_, PyModule>) -> PyResult<()> {
    m.add_function(wrap_pyfunction!(initialize_tracing, m)?)?;

    Ok(())
}

Create an instance of RustTracingIntegration and add it to your list of integrations when initializing the Sentry SDK.

main.py
Copied
import sentry_sdk
from sentry_sdk.integrations.rust_tracing import RustTracingIntegration

import my_rust_extension

async def main():
    sentry_sdk.init(
        dsn="https://examplePublicKey@o0.ingest.sentry.io/0",
        # Set traces_sample_rate to 1.0 to capture 100%
        # of transactions for tracing.
        traces_sample_rate=1.0,
        # Set profiles_sample_rate to 1.0 to profile 100%
        # of sampled transactions.
        # We recommend adjusting this value in production.
        profiles_sample_rate=1.0,
        integrations=[
            RustTracingIntegration(
                "my_rust_extension",
                my_rust_extension.initialize_tracing,
                include_tracing_fields=True,
            ),
        ],
    )

    # your code goes here.
    ...

asyncio.run(main())

A simple way to check if the integration is hooked up correctly is to set a custom event_type_mapping and span_filter that prints or logs tracing event metadata and then call a Python function that uses your Rust native extension.

Copied
from sentry_sdk.integrations.rust_tracing import (
    default_event_type_mapping,
    default_span_filter,
    EventTypeMapping,
    RustTracingIntegration,
)

import my_rust_extension

def custom_event_type_mapping(metadata: dict) -> EventTypeMapping:
    print(metadata)
    return default_event_type_mapping(metadata)

def custom_span_filter(metadata: dict) -> bool:
    print(metadata)
    return default_span_filter(metadata)

sentry_sdk.init(
    # ...
    integrations=[
        RustTracingIntegration(
            "my_rust_extension",
            my_rust_extension.initialize_tracing,
            event_type_mapping=custom_event_type_mapping,
            span_filter=custom_span_filter,
        ),
    ],
)

To see the results on sentry.io, go to the Traces section for your project and search for a Python span that calls a function from your Rust native extension. If the integration is working and the Rust function is instrumented with the Rust tracing framework, then the Python span will have a Rust child, and the Rust child may have a whole tree of Rust spans beneath it.

The pyo3-python-tracing-subscriber crate has a working example of a Sentry integration.

RustTracingIntegration accepts a few arguments:

  • identifier (required)

    A unique identifier for this native extension. If your project uses more than one Rust native extension, each of them needs its own RustTracingIntegration.

  • initializer (required)

    A function from your native extension that RustTracingIntegration can call to subscribe to tracing events.

    See the initialize_tracing example in the Configure section above

  • event_type_mapping (optional)

    A function that decides what type of Sentry event to create for a given tracing event.

    It takes a single argument: a dictionary containing data from tracing::Metadata.

    It returns a sentry_sdk.integrations.rust_tracing.EventTypeMapping.

    Uses sentry_sdk.integrations.rust_tracing.default_event_type_mapping by default.

  • span_filter (optional)

    A function that decides whether to drop a given tracing span.

    It takes a single argument: a dictionary containing data from tracing::Metadata.

    It returns True if a span should be processed and False if it should be dropped.

    Uses sentry_sdk.integrations.rust_tracing.default_span_filter by default.

  • include_tracing_fields (optional)

    A boolean controlling whether the values of a tracing span's key-value fields will be attached to the corresponding Sentry span.

    If it is None, this behavior will be controlled by the send_default_pii option set during SDK initialization. If it is False, field values will be redacted on Sentry spans. If it is True, field values will be included on Sentry spans.

    The default value of this option is None.

  • Python: 3.7+
  • Rust: 1.63+
Help improve this content
Our documentation is open source and available on GitHub. Your contributions are welcome, whether fixing a typo (drat!) or suggesting an update ("yeah, this would be better").