logbrew-fastapi 0.1.0

FastAPI integration for capturing LogBrew request spans and exceptions.

logbrew-fastapi

FastAPI integration for capturing LogBrew request spans and exceptions with the public Python SDK.

Install

python3 -m pip install logbrew-sdk logbrew-fastapi
python3 -m logbrew_fastapi.examples --help
python3 -m logbrew_fastapi.examples --list
python3 -m logbrew_fastapi.examples readme-example
python3 -m logbrew_fastapi.examples real-user-smoke
python3 -m logbrew_fastapi.examples

The package is typed, ships py.typed, depends on the core logbrew-sdk, and keeps FastAPI as a normal framework dependency instead of bundling or monkeypatching the user's app.

Example

from fastapi import FastAPI
from logbrew_fastapi import add_logbrew_middleware
from logbrew_sdk import LogBrewClient, RecordingTransport

client = LogBrewClient.create(
    api_key="LOGBREW_API_KEY",
    sdk_name="logbrew-fastapi",
    sdk_version="0.1.0",
)
transport = RecordingTransport.always_accept()
app = FastAPI()
add_logbrew_middleware(
    app,
    client=client,
    transport=transport,
    span_id_factory=lambda: "b7ad6b7169203331",
)


@app.get("/health")
def health() -> dict[str, bool]:
    return {"ok": True}

add_logbrew_middleware() records successful requests as span events, records unhandled handler exceptions as issue plus error-span events, and flushes through the provided transport after each response. If no transport is provided, events stay queued on the core client so the app can flush them itself.

When an incoming request has a valid W3C traceparent header, request capture continues that trace by using the incoming traceId and parent span id while creating a fresh child span id. Missing or malformed traceparent headers keep the existing synthetic request span behavior so bad client headers do not break the app. Automatic metadata uses the request path without query text. Use span_id_factory only when tests need deterministic child span ids.

By default, transport failures do not break the FastAPI response path. Set raise_flush_errors=True in test environments when you want misconfigured transport behavior to fail loudly.

Use a clearly fake placeholder like LOGBREW_API_KEY in local examples and tests.