llama-stack-mirror/llama_stack/providers/inline/telemetry/meta_reference/telemetry.py
Ben Browning 6d20b720b8
feat: Propagate W3C trace context headers from clients (#2153)
# What does this PR do?

This extracts the W3C trace context headers (traceparent and tracestate)
from incoming requests, stuffs them as attributes on the spans we
create, and uses them within the tracing provider implementation to
actually wrap our spans in the proper context.

What this means in practice is that when a client (such as an OpenAI
client) is instrumented to create these traces, we'll continue that
distributed trace within Llama Stack as opposed to creating our own root
span that breaks the distributed trace between client and server.

It's slightly awkward to do this in Llama Stack because our Tracing API
knows nothing about opentelemetry, W3C trace headers, etc - that's only
knowledge the specific provider implementation has. So, that's why the
trace headers get extracted by in the server code but not actually used
until the provider implementation to form the proper context.

This also centralizes how we were adding the `__root__` and
`__root_span__` attributes, as those two were being added in different
parts of the code instead of from a single place.

Closes #2097

## Test Plan

This was tested manually using the helpful scripts from #2097. I
verified that Llama Stack properly joined the client's span when the
client was instrumented for distributed tracing, and that Llama Stack
properly started its own root span when the incoming request was not
part of an existing trace.

Here's an example of the joined spans:

![Screenshot 2025-05-13 at 8 46
09 AM](https://github.com/user-attachments/assets/dbefda28-9faa-4339-a08d-1441efefc149)

Signed-off-by: Ben Browning <bbrownin@redhat.com>
2025-05-19 18:56:54 -07:00

295 lines
12 KiB
Python

# Copyright (c) Meta Platforms, Inc. and affiliates.
# All rights reserved.
#
# This source code is licensed under the terms described in the LICENSE file in
# the root directory of this source tree.
import threading
from typing import Any
from opentelemetry import metrics, trace
from opentelemetry.exporter.otlp.proto.http.metric_exporter import OTLPMetricExporter
from opentelemetry.exporter.otlp.proto.http.trace_exporter import OTLPSpanExporter
from opentelemetry.sdk.metrics import MeterProvider
from opentelemetry.sdk.metrics.export import PeriodicExportingMetricReader
from opentelemetry.sdk.resources import Resource
from opentelemetry.sdk.trace import TracerProvider
from opentelemetry.sdk.trace.export import BatchSpanProcessor
from opentelemetry.semconv.resource import ResourceAttributes
from opentelemetry.trace.propagation.tracecontext import TraceContextTextMapPropagator
from llama_stack.apis.telemetry import (
Event,
MetricEvent,
MetricLabelMatcher,
MetricQueryType,
QueryCondition,
QueryMetricsResponse,
QuerySpanTreeResponse,
QueryTracesResponse,
Span,
SpanEndPayload,
SpanStartPayload,
SpanStatus,
StructuredLogEvent,
Telemetry,
Trace,
UnstructuredLogEvent,
)
from llama_stack.distribution.datatypes import Api
from llama_stack.providers.inline.telemetry.meta_reference.console_span_processor import (
ConsoleSpanProcessor,
)
from llama_stack.providers.inline.telemetry.meta_reference.sqlite_span_processor import (
SQLiteSpanProcessor,
)
from llama_stack.providers.utils.telemetry.dataset_mixin import TelemetryDatasetMixin
from llama_stack.providers.utils.telemetry.sqlite_trace_store import SQLiteTraceStore
from llama_stack.providers.utils.telemetry.tracing import ROOT_SPAN_MARKERS
from .config import TelemetryConfig, TelemetrySink
_GLOBAL_STORAGE: dict[str, dict[str | int, Any]] = {
"active_spans": {},
"counters": {},
"gauges": {},
"up_down_counters": {},
}
_global_lock = threading.Lock()
_TRACER_PROVIDER = None
def is_tracing_enabled(tracer):
with tracer.start_as_current_span("check_tracing") as span:
return span.is_recording()
class TelemetryAdapter(TelemetryDatasetMixin, Telemetry):
def __init__(self, config: TelemetryConfig, deps: dict[Api, Any]) -> None:
self.config = config
self.datasetio_api = deps.get(Api.datasetio)
self.meter = None
resource = Resource.create(
{
ResourceAttributes.SERVICE_NAME: self.config.service_name,
}
)
global _TRACER_PROVIDER
# Initialize the correct span processor based on the provider state.
# This is needed since once the span processor is set, it cannot be unset.
# Recreating the telemetry adapter multiple times will result in duplicate span processors.
# Since the library client can be recreated multiple times in a notebook,
# the kernel will hold on to the span processor and cause duplicate spans to be written.
if _TRACER_PROVIDER is None:
provider = TracerProvider(resource=resource)
trace.set_tracer_provider(provider)
_TRACER_PROVIDER = provider
if TelemetrySink.OTEL_TRACE in self.config.sinks:
span_exporter = OTLPSpanExporter(
endpoint=self.config.otel_trace_endpoint,
)
span_processor = BatchSpanProcessor(span_exporter)
trace.get_tracer_provider().add_span_processor(span_processor)
if TelemetrySink.OTEL_METRIC in self.config.sinks:
metric_reader = PeriodicExportingMetricReader(
OTLPMetricExporter(
endpoint=self.config.otel_metric_endpoint,
)
)
metric_provider = MeterProvider(resource=resource, metric_readers=[metric_reader])
metrics.set_meter_provider(metric_provider)
if TelemetrySink.SQLITE in self.config.sinks:
trace.get_tracer_provider().add_span_processor(SQLiteSpanProcessor(self.config.sqlite_db_path))
if TelemetrySink.CONSOLE in self.config.sinks:
trace.get_tracer_provider().add_span_processor(ConsoleSpanProcessor())
if TelemetrySink.OTEL_METRIC in self.config.sinks:
self.meter = metrics.get_meter(__name__)
if TelemetrySink.SQLITE in self.config.sinks:
self.trace_store = SQLiteTraceStore(self.config.sqlite_db_path)
self._lock = _global_lock
async def initialize(self) -> None:
pass
async def shutdown(self) -> None:
trace.get_tracer_provider().force_flush()
async def log_event(self, event: Event, ttl_seconds: int = 604800) -> None:
if isinstance(event, UnstructuredLogEvent):
self._log_unstructured(event, ttl_seconds)
elif isinstance(event, MetricEvent):
self._log_metric(event)
elif isinstance(event, StructuredLogEvent):
self._log_structured(event, ttl_seconds)
else:
raise ValueError(f"Unknown event type: {event}")
async def query_metrics(
self,
metric_name: str,
start_time: int,
end_time: int | None = None,
granularity: str | None = "1d",
query_type: MetricQueryType = MetricQueryType.RANGE,
label_matchers: list[MetricLabelMatcher] | None = None,
) -> QueryMetricsResponse:
raise NotImplementedError("Querying metrics is not implemented")
def _log_unstructured(self, event: UnstructuredLogEvent, ttl_seconds: int) -> None:
with self._lock:
# Use global storage instead of instance storage
span_id = int(event.span_id, 16)
span = _GLOBAL_STORAGE["active_spans"].get(span_id)
if span:
timestamp_ns = int(event.timestamp.timestamp() * 1e9)
span.add_event(
name=event.type,
attributes={
"message": event.message,
"severity": event.severity.value,
"__ttl__": ttl_seconds,
**(event.attributes or {}),
},
timestamp=timestamp_ns,
)
else:
print(f"Warning: No active span found for span_id {span_id}. Dropping event: {event}")
def _get_or_create_counter(self, name: str, unit: str) -> metrics.Counter:
assert self.meter is not None
if name not in _GLOBAL_STORAGE["counters"]:
_GLOBAL_STORAGE["counters"][name] = self.meter.create_counter(
name=name,
unit=unit,
description=f"Counter for {name}",
)
return _GLOBAL_STORAGE["counters"][name]
def _get_or_create_gauge(self, name: str, unit: str) -> metrics.ObservableGauge:
assert self.meter is not None
if name not in _GLOBAL_STORAGE["gauges"]:
_GLOBAL_STORAGE["gauges"][name] = self.meter.create_gauge(
name=name,
unit=unit,
description=f"Gauge for {name}",
)
return _GLOBAL_STORAGE["gauges"][name]
def _log_metric(self, event: MetricEvent) -> None:
if self.meter is None:
return
if isinstance(event.value, int):
counter = self._get_or_create_counter(event.metric, event.unit)
counter.add(event.value, attributes=event.attributes)
elif isinstance(event.value, float):
up_down_counter = self._get_or_create_up_down_counter(event.metric, event.unit)
up_down_counter.add(event.value, attributes=event.attributes)
def _get_or_create_up_down_counter(self, name: str, unit: str) -> metrics.UpDownCounter:
assert self.meter is not None
if name not in _GLOBAL_STORAGE["up_down_counters"]:
_GLOBAL_STORAGE["up_down_counters"][name] = self.meter.create_up_down_counter(
name=name,
unit=unit,
description=f"UpDownCounter for {name}",
)
return _GLOBAL_STORAGE["up_down_counters"][name]
def _log_structured(self, event: StructuredLogEvent, ttl_seconds: int) -> None:
with self._lock:
span_id = int(event.span_id, 16)
tracer = trace.get_tracer(__name__)
if event.attributes is None:
event.attributes = {}
event.attributes["__ttl__"] = ttl_seconds
# Extract these W3C trace context attributes so they are not written to
# underlying storage, as we just need them to propagate the trace context.
traceparent = event.attributes.pop("traceparent", None)
tracestate = event.attributes.pop("tracestate", None)
if traceparent:
# If we have a traceparent header value, we're not the root span.
for root_attribute in ROOT_SPAN_MARKERS:
event.attributes.pop(root_attribute, None)
if isinstance(event.payload, SpanStartPayload):
# Check if span already exists to prevent duplicates
if span_id in _GLOBAL_STORAGE["active_spans"]:
return
context = None
if event.payload.parent_span_id:
parent_span_id = int(event.payload.parent_span_id, 16)
parent_span = _GLOBAL_STORAGE["active_spans"].get(parent_span_id)
context = trace.set_span_in_context(parent_span)
elif traceparent:
carrier = {
"traceparent": traceparent,
"tracestate": tracestate,
}
context = TraceContextTextMapPropagator().extract(carrier=carrier)
span = tracer.start_span(
name=event.payload.name,
context=context,
attributes=event.attributes or {},
)
_GLOBAL_STORAGE["active_spans"][span_id] = span
elif isinstance(event.payload, SpanEndPayload):
span = _GLOBAL_STORAGE["active_spans"].get(span_id)
if span:
if event.attributes:
span.set_attributes(event.attributes)
status = (
trace.Status(status_code=trace.StatusCode.OK)
if event.payload.status == SpanStatus.OK
else trace.Status(status_code=trace.StatusCode.ERROR)
)
span.set_status(status)
span.end()
_GLOBAL_STORAGE["active_spans"].pop(span_id, None)
else:
raise ValueError(f"Unknown structured log event: {event}")
async def query_traces(
self,
attribute_filters: list[QueryCondition] | None = None,
limit: int | None = 100,
offset: int | None = 0,
order_by: list[str] | None = None,
) -> QueryTracesResponse:
return QueryTracesResponse(
data=await self.trace_store.query_traces(
attribute_filters=attribute_filters,
limit=limit,
offset=offset,
order_by=order_by,
)
)
async def get_trace(self, trace_id: str) -> Trace:
return await self.trace_store.get_trace(trace_id)
async def get_span(self, trace_id: str, span_id: str) -> Span:
return await self.trace_store.get_span(trace_id, span_id)
async def get_span_tree(
self,
span_id: str,
attributes_to_return: list[str] | None = None,
max_depth: int | None = None,
) -> QuerySpanTreeResponse:
return QuerySpanTreeResponse(
data=await self.trace_store.get_span_tree(
span_id=span_id,
attributes_to_return=attributes_to_return,
max_depth=max_depth,
)
)