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FastlyLogHandler

Classin logfastly-compute 0.1.3View source

Extends logging.Handler.

A logging handler that sends logs to a Fastly endpoint.

This handler integrates with Python's standard logging framework, allowing you to use familiar logging patterns with Fastly's Real-Time Log Streaming.

The handler supports routing logs from different loggers to different endpoints using an endpoint_mapper function.

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import logging
from fastly_compute import FastlyLogHandler


# Simple: single endpoint for all loggers
handler = FastlyLogHandler("my_logs")
logger = logging.getLogger("my_app")
logger.addHandler(handler)


# Advanced: route different loggers to different endpoints
def route_logs(logger_name: str) -> str:
    if logger_name.startswith("api"):
        return "api-logs"
    elif logger_name.startswith("worker"):
        return "worker-logs"
    return "app-logs"  # default


handler = FastlyLogHandler(endpoint_mapper=route_logs)


# Or use a dict for simple mappings
endpoint_map = {"api": "api-logs", "worker": "worker-logs"}
handler = FastlyLogHandler(
    "default",
    endpoint_mapper=lambda name: endpoint_map.get(name, "app-logs")
)


# Use logger
logger.info("Request received", extra={"user_id": 123})
logger.error("Error processing request", exc_info=True)

Constructor

View source
FastlyLogHandler(default_endpoint: str | None, endpoint_mapper: Callable[[str], str | None] | None = None, level=logging.NOTSET)

Initialize the handler.

Parameters

default_endpoint: str | None

The default endpoint name (used when no mapper provided)

endpoint_mapper: Callable[[str], str | None] | Noneoptional = None

Optional callable that maps logger name to endpoint name. Signature: (loggername: str) -> endpointname: str

level: Anyoptional = logging.NOTSET

Minimum logging level to handle (default: NOTSET)

Throws

  • ValueError — If neither defaultendpoint nor endpointmapper is provided
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# Simple: single endpoint
handler = FastlyLogHandler("my_logs")


# Advanced: route by logger name
handler = FastlyLogHandler(
    endpoint_mapper=lambda name: f"{name}-logs"
)


# With fallback
handler = FastlyLogHandler(
    default_endpoint="app-logs",
    endpoint_mapper=lambda name: "api-logs" if "api" in name else None
)

Methods

close

View source
close()

Close the handler and release all endpoint resources.

This is called automatically when the handler is garbage collected or when logging.shutdown() is called.

emit

View source
emit(record: logging.LogRecord)

Emit a record to the Fastly logging endpoint.

This method is called automatically by the logging framework. You should not need to call it directly.

The endpoint is determined by calling endpointmapper with the logger name, or using the defaultendpoint.

Parameters

record: logging.LogRecord

The log record to emit

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