ref(tracing): Simplify backwards-compat code (#3379)

With this change, we aim to simplify the backwards-compatibility code
for POTel tracing.

We do this as follows:
  - Remove `start_*` functions from `tracing`
  - Remove unused parameters from `tracing.POTelSpan.__init__`.
  - Make all parameters to `tracing.POTelSpan.__init__` kwarg-only.
  - Allow `tracing.POTelSpan.__init__` to accept arbitrary kwargs,
    which are all ignored, for compatibility with old `Span` interface.
  - Completely remove `start_inactive_span`, since inactive spans can
    be created by setting `active=False` when constructing a
    `POTelSpan`.

Author: szokeasaurusrex

sentry_sdk/api.py

@@ -77,7 +77,6 @@ def overload(x):
     "set_tags",
     "set_user",
     "start_span",
-    "start_inactive_span",
     "start_transaction",
     "trace",
     "monitor",
@@ -338,14 +337,11 @@ def start_span(
     **kwargs,  # type: Any
 ):
     # type: (...) -> POTelSpan
-    return tracing.start_span(**kwargs)
-
-
-def start_inactive_span(
-    **kwargs,  # type: Any
-):
-    # type: (...) -> POTelSpan
-    return tracing.start_inactive_span(**kwargs)
+    """
+    Alias for tracing.POTelSpan constructor. The method signature is the same.
+    """
+    # TODO: Consider adding type hints to the method signature.
+    return tracing.POTelSpan(**kwargs)
 
 
 def start_transaction(
@@ -387,7 +383,7 @@ def start_transaction(
         constructor. See :py:class:`sentry_sdk.tracing.Transaction` for
         available arguments.
     """
-    return tracing.start_transaction(transaction, custom_sampling_context, **kwargs)
+    return start_span(**kwargs)
 
 
 def set_measurement(name, value, unit=""):

sentry_sdk/tracing.py

@@ -1249,21 +1249,19 @@ class POTelSpan:
 
     def __init__(
         self,
+        *,
         active=True,  # type: bool
-        trace_id=None,  # type: Optional[str]
-        span_id=None,  # type: Optional[str]
-        parent_span_id=None,  # type: Optional[str]
-        same_process_as_parent=True,  # type: bool
-        sampled=None,  # type: Optional[bool]
         op=None,  # type: Optional[str]
         description=None,  # type: Optional[str]
-        status=None,  # type: Optional[str]
-        containing_transaction=None,  # type: Optional[Transaction]
-        start_timestamp=None,  # type: Optional[Union[datetime, float]]
-        scope=None,  # type: Optional[sentry_sdk.Scope]
         origin="manual",  # type: str
+        **_,  # type: dict[str, object]
     ):
         # type: (...) -> None
+        """
+        For backwards compatibility with old the old Span interface, this class
+        accepts arbitrary keyword arguments, in addition to the ones explicitly
+        listed in the signature. These additional arguments are ignored.
+        """
         from sentry_sdk.integrations.opentelemetry.consts import SentrySpanAttribute
 
         self._otel_span = tracer.start_span(description or op or "")  # XXX
@@ -1443,19 +1441,6 @@ async def my_async_function():
         return start_child_span_decorator
 
 
-def start_span(*args, **kwargs):
-    return POTelSpan(*args, active=True, **kwargs)
-
-
-def start_inactive_span(*args, **kwargs):
-    return POTelSpan(*args, active=False, **kwargs)
-
-
-def start_transaction(*args, **kwargs):
-    # XXX force_transaction?
-    return POTelSpan(*args, active=True, **kwargs)
-
-
 # Circular imports
 
 from sentry_sdk.tracing_utils import (