Remove custom_sampling_context

Author: sentrivana

MIGRATION_GUIDE.md

@@ -19,11 +19,13 @@ Looking to upgrade from Sentry SDK 2.x to 3.x? Here's a comprehensive list of wh
 - Redis integration: In Redis pipeline spans there is no `span["data"]["redis.commands"]` that contains a dict `{"count": 3, "first_ten": ["cmd1", "cmd2", ...]}` but instead `span["data"]["redis.commands.count"]` (containing `3`) and `span["data"]["redis.commands.first_ten"]` (containing `["cmd1", "cmd2", ...]`).
 - clickhouse-driver integration: The query is now available under the `db.query.text` span attribute (only if `send_default_pii` is `True`).
 - `sentry_sdk.init` now returns `None` instead of a context manager.
+- The sampling context accessible in `traces_sampler` has changed. It now contains all span attributes. The original `sampling_context["transaction_context"]["name"]` and `sampling_context["transaction_context"]["op"]` are now accessible as `sampling_context["sentry_name"]` and `sampling_context["sentry_op"]`, respectively.
 
 ### Removed
 
 - Spans no longer have a `description`. Use `name` instead.
 - Dropped support for Python 3.6.
+- The `custom_sampling_context` parameter of `start_transaction` has been removed.
 - The PyMongo integration no longer sets tags. The data is still accessible via span attributes.
 - The PyMongo integration doesn't set `operation_ids` anymore. The individual IDs (`operation_id`, `request_id`, `session_id`) are now accessible as separate span attributes.
 - `sentry_sdk.metrics` and associated metrics APIs have been removed as Sentry no longer accepts metrics data in this form. See https://sentry.zendesk.com/hc/en-us/articles/26369339769883-Upcoming-API-Changes-to-Metrics

sentry_sdk/api.py

@@ -40,7 +40,6 @@
         ExcInfo,
         MeasurementUnit,
         LogLevelStr,
-        SamplingContext,
     )
     from sentry_sdk.tracing import Span, TransactionKwargs
 
@@ -239,12 +238,8 @@ def flush(
     return get_client().flush(timeout=timeout, callback=callback)
 
 
-def start_span(
-    *,
-    custom_sampling_context=None,
-    **kwargs,  # type: Any
-):
-    # type: (...) -> POTelSpan
+def start_span(**kwargs):
+    # type: (type.Any) -> POTelSpan
     """
     Start and return a span.
 
@@ -257,13 +252,11 @@ def start_span(
     of the `with` block. If not using context managers, call the `finish()`
     method.
     """
-    # TODO: Consider adding type hints to the method signature.
-    return get_current_scope().start_span(custom_sampling_context, **kwargs)
+    return get_current_scope().start_span(**kwargs)
 
 
 def start_transaction(
     transaction=None,  # type: Optional[Transaction]
-    custom_sampling_context=None,  # type: Optional[SamplingContext]
     **kwargs,  # type: Unpack[TransactionKwargs]
 ):
     # type: (...) -> POTelSpan
@@ -295,14 +288,12 @@ def start_transaction(
 
     :param transaction: The transaction to start. If omitted, we create and
         start a new transaction.
-    :param custom_sampling_context: The transaction's custom sampling context.
     :param kwargs: Optional keyword arguments to be passed to the Transaction
         constructor. See :py:class:`sentry_sdk.tracing.Transaction` for
         available arguments.
     """
     return start_span(
         span=transaction,
-        custom_sampling_context=custom_sampling_context,
         **kwargs,
     )
 

sentry_sdk/integrations/opentelemetry/consts.py

@@ -30,3 +30,5 @@ class SentrySpanAttribute:
     NAME = "sentry.name"
     SOURCE = "sentry.source"
     CONTEXT = "sentry.context"
+    CUSTOM_SAMPLED = "sentry.custom_sampled"
+    PARENT_SAMPLED = "sentry.parent_sampled"

sentry_sdk/integrations/opentelemetry/sampler.py

@@ -2,7 +2,6 @@
 from typing import cast
 
 from opentelemetry import trace
-
 from opentelemetry.sdk.trace.sampling import Sampler, SamplingResult, Decision
 from opentelemetry.trace.span import TraceState
 
@@ -12,6 +11,7 @@
 from sentry_sdk.integrations.opentelemetry.consts import (
     TRACESTATE_SAMPLED_KEY,
     TRACESTATE_SAMPLE_RATE_KEY,
+    SentrySpanAttribute,
 )
 
 from typing import TYPE_CHECKING
@@ -118,25 +118,21 @@ def should_sample(
         if not has_tracing_enabled(client.options):
             return dropped_result(parent_span_context, attributes)
 
-        sample_rate = None
+        # Explicit sampled value provided at start_span
+        if attributes.get(SentrySpanAttribute.CUSTOM_SAMPLED) is not None:
+            sample_rate = float(attributes[SentrySpanAttribute.CUSTOM_SAMPLED])
+            return sampled_result(parent_span_context, attributes, sample_rate)
 
-        # Check if sampled=True was passed to start_transaction
-        # TODO-anton: Do we want to keep the start_transaction(sampled=True) thing?
+        sample_rate = None
 
         # Check if there is a traces_sampler
         # Traces_sampler is responsible to check parent sampled to have full transactions.
         has_traces_sampler = callable(client.options.get("traces_sampler"))
         if has_traces_sampler:
-            # TODO-anton: Make proper sampling_context
-            # TODO-neel-potel: Make proper sampling_context
-            sampling_context = {
-                "transaction_context": {
-                    "name": name,
-                },
-                "parent_sampled": get_parent_sampled(parent_span_context, trace_id),
-            }
-
-            sample_rate = client.options["traces_sampler"](sampling_context)
+            attributes[SentrySpanAttribute.PARENT_SAMPLED] = get_parent_sampled(
+                parent_span_context, trace_id
+            )
+            sample_rate = client.options["traces_sampler"](attributes)
 
         else:
             # Check if there is a parent with a sampling decision

sentry_sdk/integrations/opentelemetry/scope.py

@@ -123,7 +123,9 @@ def start_transaction(self, custom_sampling_context=None, **kwargs):
 
     def start_span(self, custom_sampling_context=None, **kwargs):
         # type: (Optional[SamplingContext], Any) -> POTelSpan
-        return POTelSpan(**kwargs, scope=self)
+        return POTelSpan(
+            **kwargs, custom_sampling_context=custom_sampling_context, scope=self
+        )
 
 
 _INITIAL_CURRENT_SCOPE = PotelScope(ty=ScopeType.CURRENT)

sentry_sdk/tracing.py

@@ -41,6 +41,8 @@
 
     from typing_extensions import TypedDict, Unpack
 
+    from opentelemetry.utils import types as OTelSpanAttributes
+
     P = ParamSpec("P")
     R = TypeVar("R")
 
@@ -683,9 +685,9 @@ def get_trace_context(self):
             rv["status"] = self.status
 
         if self.containing_transaction:
-            rv[
-                "dynamic_sampling_context"
-            ] = self.containing_transaction.get_baggage().dynamic_sampling_context()
+            rv["dynamic_sampling_context"] = (
+                self.containing_transaction.get_baggage().dynamic_sampling_context()
+            )
 
         data = {}
 
@@ -1200,10 +1202,12 @@ def __init__(
         op=None,  # type: Optional[str]
         description=None,  # type: Optional[str]
         status=None,  # type: Optional[str]
+        sampled=None,  # type: Optional[bool]
         start_timestamp=None,  # type: Optional[Union[datetime, float]]
         origin=None,  # type: Optional[str]
         name=None,  # type: Optional[str]
         source=TRANSACTION_SOURCE_CUSTOM,  # type: str
+        attributes=None,  # type: OTelSpanAttributes
         otel_span=None,  # type: Optional[OtelSpan]
         **_,  # type: dict[str, object]
     ):
@@ -1218,6 +1222,7 @@ def __init__(
         if otel_span is not None:
             self._otel_span = otel_span
         else:
+            from sentry_sdk.integrations.opentelemetry.consts import SentrySpanAttribute
             from sentry_sdk.integrations.opentelemetry.utils import (
                 convert_to_otel_timestamp,
             )
@@ -1227,12 +1232,20 @@ def __init__(
                 start_timestamp = convert_to_otel_timestamp(start_timestamp)
 
             span_name = name or description or op or ""
-            self._otel_span = tracer.start_span(span_name, start_time=start_timestamp)
+
+            # Prepopulate some attrs to be accessible in traces_sampler
+            attributes = attributes or {}
+            attributes[SentrySpanAttribute.NAME] = span_name
+            attributes[SentrySpanAttribute.OP] = op
+            if sampled is not None:
+                attributes[SentrySpanAttribute.CUSTOM_SAMPLED] = sampled
+
+            self._otel_span = tracer.start_span(
+                span_name, start_time=start_timestamp, attributes=attributes
+            )
 
             self.origin = origin or DEFAULT_SPAN_ORIGIN
-            self.op = op
             self.description = description
-            self.name = span_name
             self.source = source
 
             if status is not None: