two version of R2R are here HEAD master

1 files changed, 1305 insertions, 0 deletions

diff --git a/.venv/lib/python3.12/site-packages/opentelemetry/sdk/trace/__init__.py b/.venv/lib/python3.12/site-packages/opentelemetry/sdk/trace/__init__.py
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@@ -0,0 +1,1305 @@
+# Copyright The OpenTelemetry Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# pylint: disable=too-many-lines
+import abc
+import atexit
+import concurrent.futures
+import json
+import logging
+import threading
+import traceback
+import typing
+from os import environ
+from time import time_ns
+from types import MappingProxyType, TracebackType
+from typing import (
+    Any,
+    Callable,
+    Dict,
+    Iterator,
+    List,
+    Mapping,
+    MutableMapping,
+    Optional,
+    Sequence,
+    Tuple,
+    Type,
+    Union,
+)
+from warnings import filterwarnings
+
+from deprecated import deprecated
+
+from opentelemetry import context as context_api
+from opentelemetry import trace as trace_api
+from opentelemetry.attributes import BoundedAttributes
+from opentelemetry.sdk import util
+from opentelemetry.sdk.environment_variables import (
+    OTEL_ATTRIBUTE_COUNT_LIMIT,
+    OTEL_ATTRIBUTE_VALUE_LENGTH_LIMIT,
+    OTEL_EVENT_ATTRIBUTE_COUNT_LIMIT,
+    OTEL_LINK_ATTRIBUTE_COUNT_LIMIT,
+    OTEL_SDK_DISABLED,
+    OTEL_SPAN_ATTRIBUTE_COUNT_LIMIT,
+    OTEL_SPAN_ATTRIBUTE_VALUE_LENGTH_LIMIT,
+    OTEL_SPAN_EVENT_COUNT_LIMIT,
+    OTEL_SPAN_LINK_COUNT_LIMIT,
+)
+from opentelemetry.sdk.resources import Resource
+from opentelemetry.sdk.trace import sampling
+from opentelemetry.sdk.trace.id_generator import IdGenerator, RandomIdGenerator
+from opentelemetry.sdk.util import BoundedList
+from opentelemetry.sdk.util.instrumentation import (
+    InstrumentationInfo,
+    InstrumentationScope,
+)
+from opentelemetry.semconv.attributes.exception_attributes import (
+    EXCEPTION_ESCAPED,
+    EXCEPTION_MESSAGE,
+    EXCEPTION_STACKTRACE,
+    EXCEPTION_TYPE,
+)
+from opentelemetry.trace import NoOpTracer, SpanContext
+from opentelemetry.trace.status import Status, StatusCode
+from opentelemetry.util import types
+from opentelemetry.util._decorator import _agnosticcontextmanager
+
+logger = logging.getLogger(__name__)
+
+_DEFAULT_OTEL_ATTRIBUTE_COUNT_LIMIT = 128
+_DEFAULT_OTEL_SPAN_ATTRIBUTE_COUNT_LIMIT = 128
+_DEFAULT_OTEL_EVENT_ATTRIBUTE_COUNT_LIMIT = 128
+_DEFAULT_OTEL_LINK_ATTRIBUTE_COUNT_LIMIT = 128
+_DEFAULT_OTEL_SPAN_EVENT_COUNT_LIMIT = 128
+_DEFAULT_OTEL_SPAN_LINK_COUNT_LIMIT = 128
+
+
+_ENV_VALUE_UNSET = ""
+
+
+class SpanProcessor:
+    """Interface which allows hooks for SDK's `Span` start and end method
+    invocations.
+
+    Span processors can be registered directly using
+    :func:`TracerProvider.add_span_processor` and they are invoked
+    in the same order as they were registered.
+    """
+
+    def on_start(
+        self,
+        span: "Span",
+        parent_context: Optional[context_api.Context] = None,
+    ) -> None:
+        """Called when a :class:`opentelemetry.trace.Span` is started.
+
+        This method is called synchronously on the thread that starts the
+        span, therefore it should not block or throw an exception.
+
+        Args:
+            span: The :class:`opentelemetry.trace.Span` that just started.
+            parent_context: The parent context of the span that just started.
+        """
+
+    def on_end(self, span: "ReadableSpan") -> None:
+        """Called when a :class:`opentelemetry.trace.Span` is ended.
+
+        This method is called synchronously on the thread that ends the
+        span, therefore it should not block or throw an exception.
+
+        Args:
+            span: The :class:`opentelemetry.trace.Span` that just ended.
+        """
+
+    def shutdown(self) -> None:
+        """Called when a :class:`opentelemetry.sdk.trace.TracerProvider` is shutdown."""
+
+    def force_flush(self, timeout_millis: int = 30000) -> bool:
+        """Export all ended spans to the configured Exporter that have not yet
+        been exported.
+
+        Args:
+            timeout_millis: The maximum amount of time to wait for spans to be
+                exported.
+
+        Returns:
+            False if the timeout is exceeded, True otherwise.
+        """
+
+
+# Temporary fix until https://github.com/PyCQA/pylint/issues/4098 is resolved
+# pylint:disable=no-member
+class SynchronousMultiSpanProcessor(SpanProcessor):
+    """Implementation of class:`SpanProcessor` that forwards all received
+    events to a list of span processors sequentially.
+
+    The underlying span processors are called in sequential order as they were
+    added.
+    """
+
+    _span_processors: Tuple[SpanProcessor, ...]
+
+    def __init__(self):
+        # use a tuple to avoid race conditions when adding a new span and
+        # iterating through it on "on_start" and "on_end".
+        self._span_processors = ()
+        self._lock = threading.Lock()
+
+    def add_span_processor(self, span_processor: SpanProcessor) -> None:
+        """Adds a SpanProcessor to the list handled by this instance."""
+        with self._lock:
+            self._span_processors += (span_processor,)
+
+    def on_start(
+        self,
+        span: "Span",
+        parent_context: Optional[context_api.Context] = None,
+    ) -> None:
+        for sp in self._span_processors:
+            sp.on_start(span, parent_context=parent_context)
+
+    def on_end(self, span: "ReadableSpan") -> None:
+        for sp in self._span_processors:
+            sp.on_end(span)
+
+    def shutdown(self) -> None:
+        """Sequentially shuts down all underlying span processors."""
+        for sp in self._span_processors:
+            sp.shutdown()
+
+    def force_flush(self, timeout_millis: int = 30000) -> bool:
+        """Sequentially calls force_flush on all underlying
+        :class:`SpanProcessor`
+
+        Args:
+            timeout_millis: The maximum amount of time over all span processors
+                to wait for spans to be exported. In case the first n span
+                processors exceeded the timeout followup span processors will be
+                skipped.
+
+        Returns:
+            True if all span processors flushed their spans within the
+            given timeout, False otherwise.
+        """
+        deadline_ns = time_ns() + timeout_millis * 1000000
+        for sp in self._span_processors:
+            current_time_ns = time_ns()
+            if current_time_ns >= deadline_ns:
+                return False
+
+            if not sp.force_flush((deadline_ns - current_time_ns) // 1000000):
+                return False
+
+        return True
+
+
+class ConcurrentMultiSpanProcessor(SpanProcessor):
+    """Implementation of :class:`SpanProcessor` that forwards all received
+    events to a list of span processors in parallel.
+
+    Calls to the underlying span processors are forwarded in parallel by
+    submitting them to a thread pool executor and waiting until each span
+    processor finished its work.
+
+    Args:
+        num_threads: The number of threads managed by the thread pool executor
+            and thus defining how many span processors can work in parallel.
+    """
+
+    def __init__(self, num_threads: int = 2):
+        # use a tuple to avoid race conditions when adding a new span and
+        # iterating through it on "on_start" and "on_end".
+        self._span_processors = ()  # type: Tuple[SpanProcessor, ...]
+        self._lock = threading.Lock()
+        self._executor = concurrent.futures.ThreadPoolExecutor(
+            max_workers=num_threads
+        )
+
+    def add_span_processor(self, span_processor: SpanProcessor) -> None:
+        """Adds a SpanProcessor to the list handled by this instance."""
+        with self._lock:
+            self._span_processors += (span_processor,)
+
+    def _submit_and_await(
+        self,
+        func: Callable[[SpanProcessor], Callable[..., None]],
+        *args: Any,
+        **kwargs: Any,
+    ):
+        futures = []
+        for sp in self._span_processors:
+            future = self._executor.submit(func(sp), *args, **kwargs)
+            futures.append(future)
+        for future in futures:
+            future.result()
+
+    def on_start(
+        self,
+        span: "Span",
+        parent_context: Optional[context_api.Context] = None,
+    ) -> None:
+        self._submit_and_await(
+            lambda sp: sp.on_start, span, parent_context=parent_context
+        )
+
+    def on_end(self, span: "ReadableSpan") -> None:
+        self._submit_and_await(lambda sp: sp.on_end, span)
+
+    def shutdown(self) -> None:
+        """Shuts down all underlying span processors in parallel."""
+        self._submit_and_await(lambda sp: sp.shutdown)
+
+    def force_flush(self, timeout_millis: int = 30000) -> bool:
+        """Calls force_flush on all underlying span processors in parallel.
+
+        Args:
+            timeout_millis: The maximum amount of time to wait for spans to be
+                exported.
+
+        Returns:
+            True if all span processors flushed their spans within the given
+            timeout, False otherwise.
+        """
+        futures = []
+        for sp in self._span_processors:  # type: SpanProcessor
+            future = self._executor.submit(sp.force_flush, timeout_millis)
+            futures.append(future)
+
+        timeout_sec = timeout_millis / 1e3
+        done_futures, not_done_futures = concurrent.futures.wait(
+            futures, timeout_sec
+        )
+        if not_done_futures:
+            return False
+
+        for future in done_futures:
+            if not future.result():
+                return False
+
+        return True
+
+
+class EventBase(abc.ABC):
+    def __init__(self, name: str, timestamp: Optional[int] = None) -> None:
+        self._name = name
+        if timestamp is None:
+            self._timestamp = time_ns()
+        else:
+            self._timestamp = timestamp
+
+    @property
+    def name(self) -> str:
+        return self._name
+
+    @property
+    def timestamp(self) -> int:
+        return self._timestamp
+
+    @property
+    @abc.abstractmethod
+    def attributes(self) -> types.Attributes:
+        pass
+
+
+class Event(EventBase):
+    """A text annotation with a set of attributes. The attributes of an event
+    are immutable.
+
+    Args:
+        name: Name of the event.
+        attributes: Attributes of the event.
+        timestamp: Timestamp of the event. If `None` it will filled
+            automatically.
+    """
+
+    def __init__(
+        self,
+        name: str,
+        attributes: types.Attributes = None,
+        timestamp: Optional[int] = None,
+        limit: Optional[int] = _DEFAULT_OTEL_SPAN_ATTRIBUTE_COUNT_LIMIT,
+    ) -> None:
+        super().__init__(name, timestamp)
+        self._attributes = attributes
+
+    @property
+    def attributes(self) -> types.Attributes:
+        return self._attributes
+
+    @property
+    def dropped_attributes(self) -> int:
+        if isinstance(self._attributes, BoundedAttributes):
+            return self._attributes.dropped
+        return 0
+
+
+def _check_span_ended(func):
+    def wrapper(self, *args, **kwargs):
+        already_ended = False
+        with self._lock:  # pylint: disable=protected-access
+            if self._end_time is None:  # pylint: disable=protected-access
+                func(self, *args, **kwargs)
+            else:
+                already_ended = True
+
+        if already_ended:
+            logger.warning("Tried calling %s on an ended span.", func.__name__)
+
+    return wrapper
+
+
+def _is_valid_link(context: SpanContext, attributes: types.Attributes) -> bool:
+    return bool(
+        context and (context.is_valid or (attributes or context.trace_state))
+    )
+
+
+class ReadableSpan:
+    """Provides read-only access to span attributes.
+
+    Users should NOT be creating these objects directly. `ReadableSpan`s are created as
+    a direct result from using the tracing pipeline via the `Tracer`.
+
+    """
+
+    def __init__(
+        self,
+        name: str,
+        context: Optional[trace_api.SpanContext] = None,
+        parent: Optional[trace_api.SpanContext] = None,
+        resource: Optional[Resource] = None,
+        attributes: types.Attributes = None,
+        events: Sequence[Event] = (),
+        links: Sequence[trace_api.Link] = (),
+        kind: trace_api.SpanKind = trace_api.SpanKind.INTERNAL,
+        instrumentation_info: Optional[InstrumentationInfo] = None,
+        status: Status = Status(StatusCode.UNSET),
+        start_time: Optional[int] = None,
+        end_time: Optional[int] = None,
+        instrumentation_scope: Optional[InstrumentationScope] = None,
+    ) -> None:
+        self._name = name
+        self._context = context
+        self._kind = kind
+        self._instrumentation_info = instrumentation_info
+        self._instrumentation_scope = instrumentation_scope
+        self._parent = parent
+        self._start_time = start_time
+        self._end_time = end_time
+        self._attributes = attributes
+        self._events = events
+        self._links = links
+        if resource is None:
+            self._resource = Resource.create({})
+        else:
+            self._resource = resource
+        self._status = status
+
+    @property
+    def dropped_attributes(self) -> int:
+        if isinstance(self._attributes, BoundedAttributes):
+            return self._attributes.dropped
+        return 0
+
+    @property
+    def dropped_events(self) -> int:
+        if isinstance(self._events, BoundedList):
+            return self._events.dropped
+        return 0
+
+    @property
+    def dropped_links(self) -> int:
+        if isinstance(self._links, BoundedList):
+            return self._links.dropped
+        return 0
+
+    @property
+    def name(self) -> str:
+        return self._name
+
+    def get_span_context(self):
+        return self._context
+
+    @property
+    def context(self):
+        return self._context
+
+    @property
+    def kind(self) -> trace_api.SpanKind:
+        return self._kind
+
+    @property
+    def parent(self) -> Optional[trace_api.SpanContext]:
+        return self._parent
+
+    @property
+    def start_time(self) -> Optional[int]:
+        return self._start_time
+
+    @property
+    def end_time(self) -> Optional[int]:
+        return self._end_time
+
+    @property
+    def status(self) -> trace_api.Status:
+        return self._status
+
+    @property
+    def attributes(self) -> types.Attributes:
+        return MappingProxyType(self._attributes or {})
+
+    @property
+    def events(self) -> Sequence[Event]:
+        return tuple(event for event in self._events)
+
+    @property
+    def links(self) -> Sequence[trace_api.Link]:
+        return tuple(link for link in self._links)
+
+    @property
+    def resource(self) -> Resource:
+        return self._resource
+
+    @property
+    @deprecated(
+        version="1.11.1", reason="You should use instrumentation_scope"
+    )
+    def instrumentation_info(self) -> Optional[InstrumentationInfo]:
+        return self._instrumentation_info
+
+    @property
+    def instrumentation_scope(self) -> Optional[InstrumentationScope]:
+        return self._instrumentation_scope
+
+    def to_json(self, indent: Optional[int] = 4):
+        parent_id = None
+        if self.parent is not None:
+            parent_id = f"0x{trace_api.format_span_id(self.parent.span_id)}"
+
+        start_time = None
+        if self._start_time:
+            start_time = util.ns_to_iso_str(self._start_time)
+
+        end_time = None
+        if self._end_time:
+            end_time = util.ns_to_iso_str(self._end_time)
+
+        status = {
+            "status_code": str(self._status.status_code.name),
+        }
+        if self._status.description:
+            status["description"] = self._status.description
+
+        f_span = {
+            "name": self._name,
+            "context": (
+                self._format_context(self._context) if self._context else None
+            ),
+            "kind": str(self.kind),
+            "parent_id": parent_id,
+            "start_time": start_time,
+            "end_time": end_time,
+            "status": status,
+            "attributes": self._format_attributes(self._attributes),
+            "events": self._format_events(self._events),
+            "links": self._format_links(self._links),
+            "resource": json.loads(self.resource.to_json()),
+        }
+
+        return json.dumps(f_span, indent=indent)
+
+    @staticmethod
+    def _format_context(context: SpanContext) -> Dict[str, str]:
+        return {
+            "trace_id": f"0x{trace_api.format_trace_id(context.trace_id)}",
+            "span_id": f"0x{trace_api.format_span_id(context.span_id)}",
+            "trace_state": repr(context.trace_state),
+        }
+
+    @staticmethod
+    def _format_attributes(
+        attributes: types.Attributes,
+    ) -> Optional[Dict[str, Any]]:
+        if attributes is not None and not isinstance(attributes, dict):
+            return dict(attributes)
+        return attributes
+
+    @staticmethod
+    def _format_events(events: Sequence[Event]) -> List[Dict[str, Any]]:
+        return [
+            {
+                "name": event.name,
+                "timestamp": util.ns_to_iso_str(event.timestamp),
+                "attributes": Span._format_attributes(  # pylint: disable=protected-access
+                    event.attributes
+                ),
+            }
+            for event in events
+        ]
+
+    @staticmethod
+    def _format_links(links: Sequence[trace_api.Link]) -> List[Dict[str, Any]]:
+        return [
+            {
+                "context": Span._format_context(  # pylint: disable=protected-access
+                    link.context
+                ),
+                "attributes": Span._format_attributes(  # pylint: disable=protected-access
+                    link.attributes
+                ),
+            }
+            for link in links
+        ]
+
+
+class SpanLimits:
+    """The limits that should be enforce on recorded data such as events, links, attributes etc.
+
+    This class does not enforce any limits itself. It only provides an a way read limits from env,
+    default values and from user provided arguments.
+
+    All limit arguments must be either a non-negative integer, ``None`` or ``SpanLimits.UNSET``.
+
+    - All limit arguments are optional.
+    - If a limit argument is not set, the class will try to read its value from the corresponding
+      environment variable.
+    - If the environment variable is not set, the default value, if any, will be used.
+
+    Limit precedence:
+
+    - If a model specific limit is set, it will be used.
+    - Else if the corresponding global limit is set, it will be used.
+    - Else if the model specific limit has a default value, the default value will be used.
+    - Else if the global limit has a default value, the default value will be used.
+
+    Args:
+        max_attributes: Maximum number of attributes that can be added to a span, event, and link.
+            Environment variable: OTEL_ATTRIBUTE_COUNT_LIMIT
+            Default: {_DEFAULT_ATTRIBUTE_COUNT_LIMIT}
+        max_events: Maximum number of events that can be added to a Span.
+            Environment variable: OTEL_SPAN_EVENT_COUNT_LIMIT
+            Default: {_DEFAULT_SPAN_EVENT_COUNT_LIMIT}
+        max_links: Maximum number of links that can be added to a Span.
+            Environment variable: OTEL_SPAN_LINK_COUNT_LIMIT
+            Default: {_DEFAULT_SPAN_LINK_COUNT_LIMIT}
+        max_span_attributes: Maximum number of attributes that can be added to a Span.
+            Environment variable: OTEL_SPAN_ATTRIBUTE_COUNT_LIMIT
+            Default: {_DEFAULT_OTEL_SPAN_ATTRIBUTE_COUNT_LIMIT}
+        max_event_attributes: Maximum number of attributes that can be added to an Event.
+            Default: {_DEFAULT_OTEL_EVENT_ATTRIBUTE_COUNT_LIMIT}
+        max_link_attributes: Maximum number of attributes that can be added to a Link.
+            Default: {_DEFAULT_OTEL_LINK_ATTRIBUTE_COUNT_LIMIT}
+        max_attribute_length: Maximum length an attribute value can have. Values longer than
+            the specified length will be truncated.
+        max_span_attribute_length: Maximum length a span attribute value can have. Values longer than
+            the specified length will be truncated.
+    """
+
+    UNSET = -1
+
+    def __init__(
+        self,
+        max_attributes: Optional[int] = None,
+        max_events: Optional[int] = None,
+        max_links: Optional[int] = None,
+        max_span_attributes: Optional[int] = None,
+        max_event_attributes: Optional[int] = None,
+        max_link_attributes: Optional[int] = None,
+        max_attribute_length: Optional[int] = None,
+        max_span_attribute_length: Optional[int] = None,
+    ):
+        # span events and links count
+        self.max_events = self._from_env_if_absent(
+            max_events,
+            OTEL_SPAN_EVENT_COUNT_LIMIT,
+            _DEFAULT_OTEL_SPAN_EVENT_COUNT_LIMIT,
+        )
+        self.max_links = self._from_env_if_absent(
+            max_links,
+            OTEL_SPAN_LINK_COUNT_LIMIT,
+            _DEFAULT_OTEL_SPAN_LINK_COUNT_LIMIT,
+        )
+
+        # attribute count
+        global_max_attributes = self._from_env_if_absent(
+            max_attributes, OTEL_ATTRIBUTE_COUNT_LIMIT
+        )
+        self.max_attributes = (
+            global_max_attributes
+            if global_max_attributes is not None
+            else _DEFAULT_OTEL_ATTRIBUTE_COUNT_LIMIT
+        )
+
+        self.max_span_attributes = self._from_env_if_absent(
+            max_span_attributes,
+            OTEL_SPAN_ATTRIBUTE_COUNT_LIMIT,
+            (
+                global_max_attributes
+                if global_max_attributes is not None
+                else _DEFAULT_OTEL_SPAN_ATTRIBUTE_COUNT_LIMIT
+            ),
+        )
+        self.max_event_attributes = self._from_env_if_absent(
+            max_event_attributes,
+            OTEL_EVENT_ATTRIBUTE_COUNT_LIMIT,
+            (
+                global_max_attributes
+                if global_max_attributes is not None
+                else _DEFAULT_OTEL_EVENT_ATTRIBUTE_COUNT_LIMIT
+            ),
+        )
+        self.max_link_attributes = self._from_env_if_absent(
+            max_link_attributes,
+            OTEL_LINK_ATTRIBUTE_COUNT_LIMIT,
+            (
+                global_max_attributes
+                if global_max_attributes is not None
+                else _DEFAULT_OTEL_LINK_ATTRIBUTE_COUNT_LIMIT
+            ),
+        )
+
+        # attribute length
+        self.max_attribute_length = self._from_env_if_absent(
+            max_attribute_length,
+            OTEL_ATTRIBUTE_VALUE_LENGTH_LIMIT,
+        )
+        self.max_span_attribute_length = self._from_env_if_absent(
+            max_span_attribute_length,
+            OTEL_SPAN_ATTRIBUTE_VALUE_LENGTH_LIMIT,
+            # use global attribute length limit as default
+            self.max_attribute_length,
+        )
+
+    def __repr__(self):
+        return f"{type(self).__name__}(max_span_attributes={self.max_span_attributes}, max_events_attributes={self.max_event_attributes}, max_link_attributes={self.max_link_attributes}, max_attributes={self.max_attributes}, max_events={self.max_events}, max_links={self.max_links}, max_attribute_length={self.max_attribute_length})"
+
+    @classmethod
+    def _from_env_if_absent(
+        cls, value: Optional[int], env_var: str, default: Optional[int] = None
+    ) -> Optional[int]:
+        if value == cls.UNSET:
+            return None
+
+        err_msg = "{} must be a non-negative integer but got {}"
+
+        # if no value is provided for the limit, try to load it from env
+        if value is None:
+            # return default value if env var is not set
+            if env_var not in environ:
+                return default
+
+            str_value = environ.get(env_var, "").strip().lower()
+            if str_value == _ENV_VALUE_UNSET:
+                return None
+
+            try:
+                value = int(str_value)
+            except ValueError:
+                raise ValueError(err_msg.format(env_var, str_value))
+
+        if value < 0:
+            raise ValueError(err_msg.format(env_var, value))
+        return value
+
+
+_UnsetLimits = SpanLimits(
+    max_attributes=SpanLimits.UNSET,
+    max_events=SpanLimits.UNSET,
+    max_links=SpanLimits.UNSET,
+    max_span_attributes=SpanLimits.UNSET,
+    max_event_attributes=SpanLimits.UNSET,
+    max_link_attributes=SpanLimits.UNSET,
+    max_attribute_length=SpanLimits.UNSET,
+    max_span_attribute_length=SpanLimits.UNSET,
+)
+
+# not removed for backward compat. please use SpanLimits instead.
+SPAN_ATTRIBUTE_COUNT_LIMIT = SpanLimits._from_env_if_absent(  # pylint: disable=protected-access
+    None,
+    OTEL_SPAN_ATTRIBUTE_COUNT_LIMIT,
+    _DEFAULT_OTEL_SPAN_ATTRIBUTE_COUNT_LIMIT,
+)
+
+
+class Span(trace_api.Span, ReadableSpan):
+    """See `opentelemetry.trace.Span`.
+
+    Users should create `Span` objects via the `Tracer` instead of this
+    constructor.
+
+    Args:
+        name: The name of the operation this span represents
+        context: The immutable span context
+        parent: This span's parent's `opentelemetry.trace.SpanContext`, or
+            None if this is a root span
+        sampler: The sampler used to create this span
+        trace_config: TODO
+        resource: Entity producing telemetry
+        attributes: The span's attributes to be exported
+        events: Timestamped events to be exported
+        links: Links to other spans to be exported
+        span_processor: `SpanProcessor` to invoke when starting and ending
+            this `Span`.
+        limits: `SpanLimits` instance that was passed to the `TracerProvider`
+    """
+
+    def __new__(cls, *args, **kwargs):
+        if cls is Span:
+            raise TypeError("Span must be instantiated via a tracer.")
+        return super().__new__(cls)
+
+    # pylint: disable=too-many-locals
+    def __init__(
+        self,
+        name: str,
+        context: trace_api.SpanContext,
+        parent: Optional[trace_api.SpanContext] = None,
+        sampler: Optional[sampling.Sampler] = None,
+        trace_config: None = None,  # TODO
+        resource: Optional[Resource] = None,
+        attributes: types.Attributes = None,
+        events: Optional[Sequence[Event]] = None,
+        links: Sequence[trace_api.Link] = (),
+        kind: trace_api.SpanKind = trace_api.SpanKind.INTERNAL,
+        span_processor: SpanProcessor = SpanProcessor(),
+        instrumentation_info: Optional[InstrumentationInfo] = None,
+        record_exception: bool = True,
+        set_status_on_exception: bool = True,
+        limits=_UnsetLimits,
+        instrumentation_scope: Optional[InstrumentationScope] = None,
+    ) -> None:
+        if resource is None:
+            resource = Resource.create({})
+        super().__init__(
+            name=name,
+            context=context,
+            parent=parent,
+            kind=kind,
+            resource=resource,
+            instrumentation_info=instrumentation_info,
+            instrumentation_scope=instrumentation_scope,
+        )
+        self._sampler = sampler
+        self._trace_config = trace_config
+        self._record_exception = record_exception
+        self._set_status_on_exception = set_status_on_exception
+        self._span_processor = span_processor
+        self._limits = limits
+        self._lock = threading.Lock()
+        self._attributes = BoundedAttributes(
+            self._limits.max_span_attributes,
+            attributes,
+            immutable=False,
+            max_value_len=self._limits.max_span_attribute_length,
+        )
+        self._events = self._new_events()
+        if events:
+            for event in events:
+                event._attributes = BoundedAttributes(
+                    self._limits.max_event_attributes,
+                    event.attributes,
+                    max_value_len=self._limits.max_attribute_length,
+                )
+                self._events.append(event)
+
+        self._links = self._new_links(links)
+
+    def __repr__(self):
+        return f'{type(self).__name__}(name="{self._name}", context={self._context})'
+
+    def _new_events(self):
+        return BoundedList(self._limits.max_events)
+
+    def _new_links(self, links: Sequence[trace_api.Link]):
+        if not links:
+            return BoundedList(self._limits.max_links)
+
+        valid_links = []
+        for link in links:
+            if link and _is_valid_link(link.context, link.attributes):
+                # pylint: disable=protected-access
+                link._attributes = BoundedAttributes(
+                    self._limits.max_link_attributes,
+                    link.attributes,
+                    max_value_len=self._limits.max_attribute_length,
+                )
+                valid_links.append(link)
+
+        return BoundedList.from_seq(self._limits.max_links, valid_links)
+
+    def get_span_context(self):
+        return self._context
+
+    def set_attributes(
+        self, attributes: Mapping[str, types.AttributeValue]
+    ) -> None:
+        with self._lock:
+            if self._end_time is not None:
+                logger.warning("Setting attribute on ended span.")
+                return
+
+            for key, value in attributes.items():
+                self._attributes[key] = value
+
+    def set_attribute(self, key: str, value: types.AttributeValue) -> None:
+        return self.set_attributes({key: value})
+
+    @_check_span_ended
+    def _add_event(self, event: EventBase) -> None:
+        self._events.append(event)
+
+    def add_event(
+        self,
+        name: str,
+        attributes: types.Attributes = None,
+        timestamp: Optional[int] = None,
+    ) -> None:
+        attributes = BoundedAttributes(
+            self._limits.max_event_attributes,
+            attributes,
+            max_value_len=self._limits.max_attribute_length,
+        )
+        self._add_event(
+            Event(
+                name=name,
+                attributes=attributes,
+                timestamp=timestamp,
+            )
+        )
+
+    @_check_span_ended
+    def _add_link(self, link: trace_api.Link) -> None:
+        self._links.append(link)
+
+    def add_link(
+        self,
+        context: SpanContext,
+        attributes: types.Attributes = None,
+    ) -> None:
+        if not _is_valid_link(context, attributes):
+            return
+
+        attributes = BoundedAttributes(
+            self._limits.max_link_attributes,
+            attributes,
+            max_value_len=self._limits.max_attribute_length,
+        )
+        self._add_link(
+            trace_api.Link(
+                context=context,
+                attributes=attributes,
+            )
+        )
+
+    def _readable_span(self) -> ReadableSpan:
+        return ReadableSpan(
+            name=self._name,
+            context=self._context,
+            parent=self._parent,
+            resource=self._resource,
+            attributes=self._attributes,
+            events=self._events,
+            links=self._links,
+            kind=self.kind,
+            status=self._status,
+            start_time=self._start_time,
+            end_time=self._end_time,
+            instrumentation_info=self._instrumentation_info,
+            instrumentation_scope=self._instrumentation_scope,
+        )
+
+    def start(
+        self,
+        start_time: Optional[int] = None,
+        parent_context: Optional[context_api.Context] = None,
+    ) -> None:
+        with self._lock:
+            if self._start_time is not None:
+                logger.warning("Calling start() on a started span.")
+                return
+            self._start_time = (
+                start_time if start_time is not None else time_ns()
+            )
+
+        self._span_processor.on_start(self, parent_context=parent_context)
+
+    def end(self, end_time: Optional[int] = None) -> None:
+        with self._lock:
+            if self._start_time is None:
+                raise RuntimeError("Calling end() on a not started span.")
+            if self._end_time is not None:
+                logger.warning("Calling end() on an ended span.")
+                return
+
+            self._end_time = end_time if end_time is not None else time_ns()
+
+        self._span_processor.on_end(self._readable_span())
+
+    @_check_span_ended
+    def update_name(self, name: str) -> None:
+        self._name = name
+
+    def is_recording(self) -> bool:
+        return self._end_time is None
+
+    @_check_span_ended
+    def set_status(
+        self,
+        status: typing.Union[Status, StatusCode],
+        description: typing.Optional[str] = None,
+    ) -> None:
+        # Ignore future calls if status is already set to OK
+        # Ignore calls to set to StatusCode.UNSET
+        if isinstance(status, Status):
+            if (
+                self._status
+                and self._status.status_code is StatusCode.OK
+                or status.status_code is StatusCode.UNSET
+            ):
+                return
+            if description is not None:
+                logger.warning(
+                    "Description %s ignored. Use either `Status` or `(StatusCode, Description)`",
+                    description,
+                )
+            self._status = status
+        elif isinstance(status, StatusCode):
+            if (
+                self._status
+                and self._status.status_code is StatusCode.OK
+                or status is StatusCode.UNSET
+            ):
+                return
+            self._status = Status(status, description)
+
+    def __exit__(
+        self,
+        exc_type: Optional[Type[BaseException]],
+        exc_val: Optional[BaseException],
+        exc_tb: Optional[TracebackType],
+    ) -> None:
+        """Ends context manager and calls `end` on the `Span`."""
+        if exc_val is not None and self.is_recording():
+            # Record the exception as an event
+            # pylint:disable=protected-access
+            if self._record_exception:
+                self.record_exception(exception=exc_val, escaped=True)
+            # Records status if span is used as context manager
+            # i.e. with tracer.start_span() as span:
+            if self._set_status_on_exception:
+                self.set_status(
+                    Status(
+                        status_code=StatusCode.ERROR,
+                        description=f"{exc_type.__name__}: {exc_val}",
+                    )
+                )
+
+        super().__exit__(exc_type, exc_val, exc_tb)
+
+    def record_exception(
+        self,
+        exception: BaseException,
+        attributes: types.Attributes = None,
+        timestamp: Optional[int] = None,
+        escaped: bool = False,
+    ) -> None:
+        """Records an exception as a span event."""
+        # TODO: keep only exception as first argument after baseline is 3.10
+        stacktrace = "".join(
+            traceback.format_exception(
+                type(exception), value=exception, tb=exception.__traceback__
+            )
+        )
+        module = type(exception).__module__
+        qualname = type(exception).__qualname__
+        exception_type = (
+            f"{module}.{qualname}"
+            if module and module != "builtins"
+            else qualname
+        )
+        _attributes: MutableMapping[str, types.AttributeValue] = {
+            EXCEPTION_TYPE: exception_type,
+            EXCEPTION_MESSAGE: str(exception),
+            EXCEPTION_STACKTRACE: stacktrace,
+            EXCEPTION_ESCAPED: str(escaped),
+        }
+        if attributes:
+            _attributes.update(attributes)
+        self.add_event(
+            name="exception", attributes=_attributes, timestamp=timestamp
+        )
+
+
+class _Span(Span):
+    """Protected implementation of `opentelemetry.trace.Span`.
+
+    This constructor exists to prevent the instantiation of the `Span` class
+    by other mechanisms than through the `Tracer`.
+    """
+
+
+class Tracer(trace_api.Tracer):
+    """See `opentelemetry.trace.Tracer`."""
+
+    def __init__(
+        self,
+        sampler: sampling.Sampler,
+        resource: Resource,
+        span_processor: Union[
+            SynchronousMultiSpanProcessor, ConcurrentMultiSpanProcessor
+        ],
+        id_generator: IdGenerator,
+        instrumentation_info: InstrumentationInfo,
+        span_limits: SpanLimits,
+        instrumentation_scope: InstrumentationScope,
+    ) -> None:
+        self.sampler = sampler
+        self.resource = resource
+        self.span_processor = span_processor
+        self.id_generator = id_generator
+        self.instrumentation_info = instrumentation_info
+        self._span_limits = span_limits
+        self._instrumentation_scope = instrumentation_scope
+
+    @_agnosticcontextmanager  # pylint: disable=protected-access
+    def start_as_current_span(
+        self,
+        name: str,
+        context: Optional[context_api.Context] = None,
+        kind: trace_api.SpanKind = trace_api.SpanKind.INTERNAL,
+        attributes: types.Attributes = None,
+        links: Optional[Sequence[trace_api.Link]] = (),
+        start_time: Optional[int] = None,
+        record_exception: bool = True,
+        set_status_on_exception: bool = True,
+        end_on_exit: bool = True,
+    ) -> Iterator[trace_api.Span]:
+        span = self.start_span(
+            name=name,
+            context=context,
+            kind=kind,
+            attributes=attributes,
+            links=links,
+            start_time=start_time,
+            record_exception=record_exception,
+            set_status_on_exception=set_status_on_exception,
+        )
+        with trace_api.use_span(
+            span,
+            end_on_exit=end_on_exit,
+            record_exception=record_exception,
+            set_status_on_exception=set_status_on_exception,
+        ) as span:
+            yield span
+
+    def start_span(  # pylint: disable=too-many-locals
+        self,
+        name: str,
+        context: Optional[context_api.Context] = None,
+        kind: trace_api.SpanKind = trace_api.SpanKind.INTERNAL,
+        attributes: types.Attributes = None,
+        links: Optional[Sequence[trace_api.Link]] = (),
+        start_time: Optional[int] = None,
+        record_exception: bool = True,
+        set_status_on_exception: bool = True,
+    ) -> trace_api.Span:
+        parent_span_context = trace_api.get_current_span(
+            context
+        ).get_span_context()
+
+        if parent_span_context is not None and not isinstance(
+            parent_span_context, trace_api.SpanContext
+        ):
+            raise TypeError(
+                "parent_span_context must be a SpanContext or None."
+            )
+
+        # is_valid determines root span
+        if parent_span_context is None or not parent_span_context.is_valid:
+            parent_span_context = None
+            trace_id = self.id_generator.generate_trace_id()
+        else:
+            trace_id = parent_span_context.trace_id
+
+        # The sampler decides whether to create a real or no-op span at the
+        # time of span creation. No-op spans do not record events, and are not
+        # exported.
+        # The sampler may also add attributes to the newly-created span, e.g.
+        # to include information about the sampling result.
+        # The sampler may also modify the parent span context's tracestate
+        sampling_result = self.sampler.should_sample(
+            context, trace_id, name, kind, attributes, links
+        )
+
+        trace_flags = (
+            trace_api.TraceFlags(trace_api.TraceFlags.SAMPLED)
+            if sampling_result.decision.is_sampled()
+            else trace_api.TraceFlags(trace_api.TraceFlags.DEFAULT)
+        )
+        span_context = trace_api.SpanContext(
+            trace_id,
+            self.id_generator.generate_span_id(),
+            is_remote=False,
+            trace_flags=trace_flags,
+            trace_state=sampling_result.trace_state,
+        )
+
+        # Only record if is_recording() is true
+        if sampling_result.decision.is_recording():
+            # pylint:disable=protected-access
+            span = _Span(
+                name=name,
+                context=span_context,
+                parent=parent_span_context,
+                sampler=self.sampler,
+                resource=self.resource,
+                attributes=sampling_result.attributes.copy(),
+                span_processor=self.span_processor,
+                kind=kind,
+                links=links,
+                instrumentation_info=self.instrumentation_info,
+                record_exception=record_exception,
+                set_status_on_exception=set_status_on_exception,
+                limits=self._span_limits,
+                instrumentation_scope=self._instrumentation_scope,
+            )
+            span.start(start_time=start_time, parent_context=context)
+        else:
+            span = trace_api.NonRecordingSpan(context=span_context)
+        return span
+
+
+class TracerProvider(trace_api.TracerProvider):
+    """See `opentelemetry.trace.TracerProvider`."""
+
+    def __init__(
+        self,
+        sampler: Optional[sampling.Sampler] = None,
+        resource: Optional[Resource] = None,
+        shutdown_on_exit: bool = True,
+        active_span_processor: Union[
+            SynchronousMultiSpanProcessor, ConcurrentMultiSpanProcessor, None
+        ] = None,
+        id_generator: Optional[IdGenerator] = None,
+        span_limits: Optional[SpanLimits] = None,
+    ) -> None:
+        self._active_span_processor = (
+            active_span_processor or SynchronousMultiSpanProcessor()
+        )
+        if id_generator is None:
+            self.id_generator = RandomIdGenerator()
+        else:
+            self.id_generator = id_generator
+        if resource is None:
+            self._resource = Resource.create({})
+        else:
+            self._resource = resource
+        if not sampler:
+            sampler = sampling._get_from_env_or_default()
+        self.sampler = sampler
+        self._span_limits = span_limits or SpanLimits()
+        disabled = environ.get(OTEL_SDK_DISABLED, "")
+        self._disabled = disabled.lower().strip() == "true"
+        self._atexit_handler = None
+
+        if shutdown_on_exit:
+            self._atexit_handler = atexit.register(self.shutdown)
+
+    @property
+    def resource(self) -> Resource:
+        return self._resource
+
+    def get_tracer(
+        self,
+        instrumenting_module_name: str,
+        instrumenting_library_version: typing.Optional[str] = None,
+        schema_url: typing.Optional[str] = None,
+        attributes: typing.Optional[types.Attributes] = None,
+    ) -> "trace_api.Tracer":
+        if self._disabled:
+            return NoOpTracer()
+        if not instrumenting_module_name:  # Reject empty strings too.
+            instrumenting_module_name = ""
+            logger.error("get_tracer called with missing module name.")
+        if instrumenting_library_version is None:
+            instrumenting_library_version = ""
+
+        filterwarnings(
+            "ignore",
+            message=(
+                r"Call to deprecated method __init__. \(You should use "
+                r"InstrumentationScope\) -- Deprecated since version 1.11.1."
+            ),
+            category=DeprecationWarning,
+            module="opentelemetry.sdk.trace",
+        )
+
+        instrumentation_info = InstrumentationInfo(
+            instrumenting_module_name,
+            instrumenting_library_version,
+            schema_url,
+        )
+
+        return Tracer(
+            self.sampler,
+            self.resource,
+            self._active_span_processor,
+            self.id_generator,
+            instrumentation_info,
+            self._span_limits,
+            InstrumentationScope(
+                instrumenting_module_name,
+                instrumenting_library_version,
+                schema_url,
+                attributes,
+            ),
+        )
+
+    def add_span_processor(self, span_processor: SpanProcessor) -> None:
+        """Registers a new :class:`SpanProcessor` for this `TracerProvider`.
+
+        The span processors are invoked in the same order they are registered.
+        """
+
+        # no lock here because add_span_processor is thread safe for both
+        # SynchronousMultiSpanProcessor and ConcurrentMultiSpanProcessor.
+        self._active_span_processor.add_span_processor(span_processor)
+
+    def shutdown(self) -> None:
+        """Shut down the span processors added to the tracer provider."""
+        self._active_span_processor.shutdown()
+        if self._atexit_handler is not None:
+            atexit.unregister(self._atexit_handler)
+            self._atexit_handler = None
+
+    def force_flush(self, timeout_millis: int = 30000) -> bool:
+        """Requests the active span processor to process all spans that have not
+        yet been processed.
+
+        By default force flush is called sequentially on all added span
+        processors. This means that span processors further back in the list
+        have less time to flush their spans.
+        To have span processors flush their spans in parallel it is possible to
+        initialize the tracer provider with an instance of
+        `ConcurrentMultiSpanProcessor` at the cost of using multiple threads.
+
+        Args:
+            timeout_millis: The maximum amount of time to wait for spans to be
+                processed.
+
+        Returns:
+            False if the timeout is exceeded, True otherwise.
+        """
+        return self._active_span_processor.force_flush(timeout_millis)