# Source code for opentelemetry.shim.opentracing_shim

    # Copyright The OpenTelemetry Authors
    # SPDX-License-Identifier: Apache-2.0

    """
    The OpenTelemetry OpenTracing shim is a library which allows an easy migration
    from OpenTracing to OpenTelemetry.

    The shim consists of a set of classes which implement the OpenTracing Python
    API while using OpenTelemetry constructs behind the scenes. Its purpose is to
    allow applications which are already instrumented using OpenTracing to start
    using OpenTelemetry with a minimal effort, without having to rewrite large
    portions of the codebase.

    To use the shim, a :class:`TracerShim` instance is created and then used as if
    it were an "ordinary" OpenTracing :class:`opentracing.Tracer`, as in the
    following example::

        import time

        from opentelemetry import trace
        from opentelemetry.sdk.trace import TracerProvider
        from opentelemetry.shim.opentracing_shim import create_tracer

        # Define which OpenTelemetry Tracer provider implementation to use.
        trace.set_tracer_provider(TracerProvider())

        # Get the OpenTelemetry TracerProvider.
        tracer_provider = trace.get_tracer_provider()

        # Create an OpenTracing shim.
        shim = create_tracer(tracer_provider)

        with shim.start_active_span("ProcessHTTPRequest"):
            print("Processing HTTP request")
            # Sleeping to mock real work.
            time.sleep(0.1)
            with shim.start_active_span("GetDataFromDB"):
                print("Getting data from DB")
                # Sleeping to mock real work.
                time.sleep(0.2)

    Note:
        While the OpenTracing Python API represents time values as the number of
        **seconds** since the epoch expressed as :obj:`float` values, the
        OpenTelemetry Python API represents time values as the number of
        **nanoseconds** since the epoch expressed as :obj:`int` values. This fact
        requires the OpenTracing shim to convert time values back and forth between
        the two representations, which involves floating point arithmetic.

        Due to the way computers represent floating point values in hardware,
        representation of decimal floating point values in binary-based hardware is
        imprecise by definition.

        The above results in **slight imprecisions** in time values passed to the
        shim via the OpenTracing API when comparing the value passed to the shim
        and the value stored in the OpenTelemetry :class:`opentelemetry.trace.Span`
        object behind the scenes. **This is not a bug in this library or in
        Python**. Rather, this is a generic problem which stems from the fact that
        not every decimal floating point number can be correctly represented in
        binary, and therefore affects other libraries and programming languages as
        well. More information about this problem can be found in the
        `Floating Point Arithmetic\\: Issues and Limitations`_ section of the
        Python documentation.

        While testing this library, the aforementioned imprecisions were observed
        to be of *less than a microsecond*.

    API
    ---
    .. _Floating Point Arithmetic\\: Issues and Limitations:
        https://docs.python.org/3/tutorial/floatingpoint.html
    """

    # TODO: make pylint use 3p opentracing module for type inference
    # pylint:disable=no-member
    from __future__ import annotations

    import logging
    from types import TracebackType
    from typing import TypeVar

    from opentracing import (
        Format,
        Scope,
        ScopeManager,
        Span,
        SpanContext,
        Tracer,
        UnsupportedFormatException,
    )
    from typing_extensions import deprecated

    from opentelemetry.baggage import get_baggage, set_baggage
    from opentelemetry.context import (
        Context,
        attach,
        create_key,
        detach,
        get_value,
        set_value,
    )
    from opentelemetry.propagate import get_global_textmap
    from opentelemetry.shim.opentracing_shim import util
    from opentelemetry.shim.opentracing_shim.version import __version__
    from opentelemetry.trace import (
        INVALID_SPAN_CONTEXT,
        Link,
        NonRecordingSpan,
        TracerProvider,
        get_current_span,
        set_span_in_context,
        use_span,
    )
    from opentelemetry.trace import SpanContext as OtelSpanContext
    from opentelemetry.trace import Tracer as OtelTracer
    from opentelemetry.util.types import Attributes

    ValueT = TypeVar("ValueT", int, float, bool, str)
    logger = logging.getLogger(__name__)
    _SHIM_KEY = create_key("scope_shim")

    def create_tracer(otel_tracer_provider: TracerProvider) -> TracerShim:
        """Creates a :class:`TracerShim` object from the provided OpenTelemetry
        :class:`opentelemetry.trace.TracerProvider`.

        The returned :class:`TracerShim` is an implementation of
        :class:`opentracing.Tracer` using OpenTelemetry under the hood.

        Args:
            otel_tracer_provider: A tracer from this provider  will be used to
                perform the actual tracing when user code is instrumented using the
                OpenTracing API.

        Returns:
            The created :class:`TracerShim`.
        """

        return TracerShim(otel_tracer_provider.get_tracer(__name__, __version__))

    class SpanContextShim(SpanContext):
        """Implements :class:`opentracing.SpanContext` by wrapping a
        :class:`opentelemetry.trace.SpanContext` object.

        Args:
            otel_context: A :class:`opentelemetry.trace.SpanContext` to be used for
                constructing the :class:`SpanContextShim`.
        """

        def __init__(self, otel_context: OtelSpanContext):
            self._otel_context = otel_context
            # Context is being used here since it must be immutable.
            self._baggage = Context()

        def unwrap(self) -> OtelSpanContext:
            """Returns the wrapped :class:`opentelemetry.trace.SpanContext`
            object.

            Returns:
                The :class:`opentelemetry.trace.SpanContext` object wrapped by this
                :class:`SpanContextShim`.
            """

            return self._otel_context

        @property
        def baggage(self) -> Context:
            """Returns the ``baggage`` associated with this object"""

            return self._baggage

    class SpanShim(Span):
        """Wraps a :class:`opentelemetry.trace.Span` object.

        Args:
            tracer: The :class:`opentracing.Tracer` that created this `SpanShim`.
            context: A :class:`SpanContextShim` which contains the context for this
                :class:`SpanShim`.
            span: A :class:`opentelemetry.trace.Span` to wrap.
        """

        def __init__(self, tracer, context: SpanContextShim, span):
            super().__init__(tracer, context)
            self._otel_span = span

        def unwrap(self):
            """Returns the wrapped :class:`opentelemetry.trace.Span` object.

            Returns:
                The :class:`opentelemetry.trace.Span` object wrapped by this
                :class:`SpanShim`.
            """

            return self._otel_span

        def set_operation_name(self, operation_name: str) -> SpanShim:
            """Updates the name of the wrapped OpenTelemetry span.

            Args:
                operation_name: The new name to be used for the underlying
                    :class:`opentelemetry.trace.Span` object.

            Returns:
                Returns this :class:`SpanShim` instance to allow call chaining.
            """

            self._otel_span.update_name(operation_name)
            return self

        def finish(self, finish_time: float | None = None):
            """Ends the OpenTelemetry span wrapped by this :class:`SpanShim`.

            If *finish_time* is provided, the time value is converted to the
            OpenTelemetry time format (number of nanoseconds since the epoch,
            expressed as an integer) and passed on to the OpenTelemetry tracer when
            ending the OpenTelemetry span. If *finish_time* isn't provided, it is
            up to the OpenTelemetry tracer implementation to generate a timestamp
            when ending the span.

            Args:
                finish_time: A value that represents the finish time expressed as
                    the number of seconds since the epoch as returned by
                    :func:`time.time()`.
            """

            end_time = finish_time
            if end_time is not None:
                end_time = util.time_seconds_to_ns(finish_time)
            self._otel_span.end(end_time=end_time)

        def set_tag(self, key: str, value: ValueT) -> SpanShim:
            """Sets an OpenTelemetry attribute on the wrapped OpenTelemetry span.

            Args:
                key: A tag key.
                value: A tag value.

            Returns:
                Returns this :class:`SpanShim` instance to allow call chaining.
            """

            self._otel_span.set_attribute(key, value)
            return self

        def log_kv(
            self, key_values: Attributes, timestamp: float | None = None
        ) -> SpanShim:
            """Logs an event for the wrapped OpenTelemetry span.

            Note:
                The OpenTracing API defines the values of *key_values* to be of any
                type. However, the OpenTelemetry API requires that the values be
                any one of the types defined in
                ``opentelemetry.trace.util.Attributes`` therefore, only these types
                are supported as values.

            Args:
                key_values: A dictionary as specified in
                    ``opentelemetry.trace.util.Attributes``.
                timestamp: Timestamp of the OpenTelemetry event, will be generated
                    automatically if omitted.

            Returns:
                Returns this :class:`SpanShim` instance to allow call chaining.
            """

            if timestamp is not None:
                event_timestamp = util.time_seconds_to_ns(timestamp)
            else:
                event_timestamp = None

            event_name = util.event_name_from_kv(key_values)
            self._otel_span.add_event(event_name, key_values, event_timestamp)
            return self

        @deprecated("This method is deprecated in favor of log_kv")
        def log(self, **kwargs):
            super().log(**kwargs)

        @deprecated("This method is deprecated in favor of log_kv")
        def log_event(self, event, payload=None):
            super().log_event(event, payload=payload)

        def set_baggage_item(self, key: str, value: str):
            """Stores a Baggage item in the span as a key/value
            pair.

            Args:
                key: A tag key.
                value: A tag value.
            """
            # pylint: disable=protected-access
            self._context._baggage = set_baggage(
                key, value, context=self._context._baggage
            )

        def get_baggage_item(self, key: str) -> object | None:
            """Retrieves value of the baggage item with the given key.

            Args:
                key: A tag key.
            Returns:
                Returns this :class:`SpanShim` instance to allow call chaining.
            """
            # pylint: disable=protected-access
            return get_baggage(key, context=self._context._baggage)

    class ScopeShim(Scope):
        """A `ScopeShim` wraps the OpenTelemetry functionality related to span
        activation/deactivation while using OpenTracing :class:`opentracing.Scope`
        objects for presentation.

        Unlike other classes in this package, the `ScopeShim` class doesn't wrap an
        OpenTelemetry class because OpenTelemetry doesn't have the notion of
        "scope" (though it *does* have similar functionality).

        There are two ways to construct a `ScopeShim` object: using the default
        initializer and using the :meth:`from_context_manager()` class method.

        It is necessary to have both ways for constructing `ScopeShim` objects
        because in some cases we need to create the object from an OpenTelemetry
        `opentelemetry.trace.Span` context manager (as returned by
        :meth:`opentelemetry.trace.use_span`), in which case our only way of
        retrieving a `opentelemetry.trace.Span` object is by calling the
        ``__enter__()`` method on the context manager, which makes the span active
        in the OpenTelemetry tracer; whereas in other cases we need to accept a
        `SpanShim` object and wrap it in a `ScopeShim`. The former is used mainly
        when the instrumentation code retrieves the currently-active span using
        `ScopeManagerShim.active`. The latter is mainly used when the
        instrumentation code activates a span using
        :meth:`ScopeManagerShim.activate`.

        Args:
            manager: The :class:`ScopeManagerShim` that created this
                :class:`ScopeShim`.
            span: The :class:`SpanShim` this :class:`ScopeShim` controls.
            span_cm: A Python context manager which yields an OpenTelemetry
                `opentelemetry.trace.Span` from its ``__enter__()`` method. Used
                by :meth:`from_context_manager` to store the context manager as
                an attribute so that it can later be closed by calling its
                ``__exit__()`` method. Defaults to `None`.
        """

        def __init__(
            self, manager: ScopeManagerShim, span: SpanShim, span_cm=None
        ):
            super().__init__(manager, span)
            self._span_cm = span_cm
            self._token = attach(set_value(_SHIM_KEY, self))

        # TODO: Change type of `manager` argument to `opentracing.ScopeManager`? We
        # need to get rid of `manager.tracer` for this.

        @classmethod
        def from_context_manager(cls, manager: ScopeManagerShim, span_cm):
            """Constructs a :class:`ScopeShim` from an OpenTelemetry
            `opentelemetry.trace.Span` context
            manager.

            The method extracts a `opentelemetry.trace.Span` object from the
            context manager by calling the context manager's ``__enter__()``
            method. This causes the span to start in the OpenTelemetry tracer.

            Example usage::

                span = otel_tracer.start_span("TestSpan")
                span_cm = opentelemetry.trace.use_span(span)
                scope_shim = ScopeShim.from_context_manager(
                    scope_manager_shim,
                    span_cm=span_cm,
                )

            Args:
                manager: The :class:`ScopeManagerShim` that created this
                    :class:`ScopeShim`.
                span_cm: A context manager as returned by
                    :meth:`opentelemetry.trace.use_span`.
            """

            # pylint: disable=unnecessary-dunder-call
            otel_span = span_cm.__enter__()
            span_context = SpanContextShim(otel_span.get_span_context())
            span = SpanShim(manager.tracer, span_context, otel_span)
            return cls(manager, span, span_cm)

        def close(self):
            """Closes the `ScopeShim`. If the `ScopeShim` was created from a
            context manager, calling this method sets the active span in the
            OpenTelemetry tracer back to the span which was active before this
            `ScopeShim` was created. In addition, if the span represented by this
            `ScopeShim` was activated with the *finish_on_close* argument set to
            `True`, calling this method will end the span.

            Warning:
                In the current state of the implementation it is possible to create
                a `ScopeShim` directly from a `SpanShim`, that is - without using
                :meth:`from_context_manager()`. For that reason we need to be able
                to end the span represented by the `ScopeShim` in this case, too.
                Please note that closing a `ScopeShim` created this way (for
                example as returned by :meth:`ScopeManagerShim.active`) **always
                ends the associated span**, regardless of the value passed in
                *finish_on_close* when activating the span.
            """
            self._end_span_scope(None, None, None)

        def __exit__(self, exc_type, exc_val, exc_tb):
            """
            Override the __exit__ method of `opentracing.scope.Scope` so we can report
            exceptions correctly in opentelemetry specification format.
            """
            self._end_span_scope(exc_type, exc_val, exc_tb)

        def _end_span_scope(
            self,
            exc_type: type[BaseException] | None,
            exc_val: BaseException | None,
            exc_tb: TracebackType | None,
        ) -> None:
            detach(self._token)
            if self._span_cm is not None:
                self._span_cm.__exit__(exc_type, exc_val, exc_tb)
            else:
                self._span.unwrap().end()

    class ScopeManagerShim(ScopeManager):
        """Implements :class:`opentracing.ScopeManager` by setting and getting the
        active `opentelemetry.trace.Span` in the OpenTelemetry tracer.

        This class keeps a reference to a :class:`TracerShim` as an attribute. This
        reference is used to communicate with the OpenTelemetry tracer. It is
        necessary to have a reference to the :class:`TracerShim` rather than the
        :class:`opentelemetry.trace.Tracer` wrapped by it because when constructing
        a :class:`SpanShim` we need to pass a reference to a
        :class:`opentracing.Tracer`.

        Args:
            tracer: A :class:`TracerShim` to use for setting and getting active
                span state.
        """

        def __init__(self, tracer: TracerShim):
            # The only thing the ``__init__()``` method on the base class does is
            # initialize `self._noop_span` and `self._noop_scope` with no-op
            # objects. Therefore, it doesn't seem useful to call it.
            # pylint: disable=super-init-not-called
            self._tracer = tracer

        def activate(self, span: SpanShim, finish_on_close: bool) -> ScopeShim:
            """Activates a :class:`SpanShim` and returns a :class:`ScopeShim` which
            represents the active span.

            Args:
                span: A :class:`SpanShim` to be activated.
                finish_on_close(:obj:`bool`): Determines whether the OpenTelemetry
                    span should be ended when the returned :class:`ScopeShim` is
                    closed.

            Returns:
                A :class:`ScopeShim` representing the activated span.
            """

            span_cm = use_span(span.unwrap(), end_on_exit=finish_on_close)
            return ScopeShim.from_context_manager(self, span_cm=span_cm)

        @property
        def active(self) -> ScopeShim:
            """Returns a :class:`ScopeShim` object representing the
            currently-active span in the OpenTelemetry tracer.

            Returns:
                A :class:`ScopeShim` representing the active span in the
                OpenTelemetry tracer, or `None` if no span is currently active.

            Warning:
                Calling :meth:`ScopeShim.close` on the :class:`ScopeShim` returned
                by this property **always ends the corresponding span**, regardless
                of the *finish_on_close* value used when activating the span. This
                is a limitation of the current implementation of the OpenTracing
                shim and is likely to be handled in future versions.
            """

            span = get_current_span()
            if span.get_span_context() == INVALID_SPAN_CONTEXT:
                return None

            try:
                return get_value(_SHIM_KEY)
            except KeyError:
                span_context = SpanContextShim(span.get_span_context())
                wrapped_span = SpanShim(self._tracer, span_context, span)
                return ScopeShim(self, span=wrapped_span)

        @property
        def tracer(self) -> TracerShim:
            """Returns the :class:`TracerShim` reference used by this
            :class:`ScopeManagerShim` for setting and getting the active span from
            the OpenTelemetry tracer.

            Returns:
                The :class:`TracerShim` used for setting and getting the active
                span.

            Warning:
                This property is *not* a part of the OpenTracing API. It is used
                internally by the current implementation of the OpenTracing shim
                and will likely be removed in future versions.
            """

            return self._tracer

    class TracerShim(Tracer):
        """Wraps a :class:`opentelemetry.trace.Tracer` object.

        This wrapper class allows using an OpenTelemetry tracer as if it were an
        OpenTracing tracer. It exposes the same methods as an "ordinary"
        OpenTracing tracer, and uses OpenTelemetry transparently for performing the
        actual tracing.

        This class depends on the *OpenTelemetry API*. Therefore, any
        implementation of a :class:`opentelemetry.trace.Tracer` should work with
        this class.

        Args:
            tracer: A :class:`opentelemetry.trace.Tracer` to use for tracing. This
                tracer will be invoked by the shim to create actual spans.
        """

        def __init__(self, tracer: OtelTracer):
            super().__init__(scope_manager=ScopeManagerShim(self))
            self._otel_tracer = tracer
            self._supported_formats = (
                Format.TEXT_MAP,
                Format.HTTP_HEADERS,
            )

        def unwrap(self):
            """Returns the :class:`opentelemetry.trace.Tracer` object that is
            wrapped by this :class:`TracerShim` and used for actual tracing.

            Returns:
                The :class:`opentelemetry.trace.Tracer` used for actual tracing.
            """

            return self._otel_tracer

        def start_active_span(
            self,
            operation_name: str,
            child_of: SpanShim | SpanContextShim | None = None,
            references: list | None = None,
            tags: Attributes = None,
            start_time: float | None = None,
            ignore_active_span: bool = False,
            finish_on_close: bool = True,
        ) -> ScopeShim:
            """Starts and activates a span. In terms of functionality, this method
            behaves exactly like the same method on a "regular" OpenTracing tracer.
            See :meth:`opentracing.Tracer.start_active_span` for more details.

            Args:
                operation_name: Name of the operation represented by
                    the new span from the perspective of the current service.
                child_of: A :class:`SpanShim` or :class:`SpanContextShim`
                    representing the parent in a "child of" reference. If
                    specified, the *references* parameter must be omitted.
                references: A list of :class:`opentracing.Reference` objects that
                    identify one or more parents of type :class:`SpanContextShim`.
                tags: A dictionary of tags.
                start_time: An explicit start time expressed as the number of
                    seconds since the epoch as returned by :func:`time.time()`.
                ignore_active_span: Ignore the currently-active span in the
                    OpenTelemetry tracer and make the created span the root span of
                    a new trace.
                finish_on_close: Determines whether the created span should end
                    automatically when closing the returned :class:`ScopeShim`.

            Returns:
                A :class:`ScopeShim` that is already activated by the
                :class:`ScopeManagerShim`.
            """

            current_span = get_current_span()

            if (
                child_of is None
                and current_span.get_span_context() is not INVALID_SPAN_CONTEXT
            ):
                child_of = SpanShim(None, None, current_span)

            span = self.start_span(
                operation_name=operation_name,
                child_of=child_of,
                references=references,
                tags=tags,
                start_time=start_time,
                ignore_active_span=ignore_active_span,
            )
            return self._scope_manager.activate(span, finish_on_close)

        def start_span(
            self,
            operation_name: str | None = None,
            child_of: SpanShim | SpanContextShim | None = None,
            references: list | None = None,
            tags: Attributes = None,
            start_time: float | None = None,
            ignore_active_span: bool = False,
        ) -> SpanShim:
            """Implements the ``start_span()`` method from the base class.

            Starts a span. In terms of functionality, this method behaves exactly
            like the same method on a "regular" OpenTracing tracer. See
            :meth:`opentracing.Tracer.start_span` for more details.

            Args:
                operation_name: Name of the operation represented by the new span
                    from the perspective of the current service.
                child_of: A :class:`SpanShim` or :class:`SpanContextShim`
                    representing the parent in a "child of" reference. If
                    specified, the *references* parameter must be omitted.
                references: A list of :class:`opentracing.Reference` objects that
                    identify one or more parents of type :class:`SpanContextShim`.
                tags: A dictionary of tags.
                start_time: An explicit start time expressed as the number of
                    seconds since the epoch as returned by :func:`time.time()`.
                ignore_active_span: Ignore the currently-active span in the
                    OpenTelemetry tracer and make the created span the root span of
                    a new trace.

            Returns:
                An already-started :class:`SpanShim` instance.
            """

            # Use active span as parent when no explicit parent is specified.
            if not ignore_active_span and not child_of:
                child_of = self.active_span

            # Use the specified parent or the active span if possible. Otherwise,
            # use a `None` parent, which triggers the creation of a new trace.
            parent = child_of.unwrap() if child_of else None
            if isinstance(parent, OtelSpanContext):
                parent = NonRecordingSpan(parent)

            valid_links = []
            if references:
                for ref in references:
                    if ref.referenced_context.unwrap() is not INVALID_SPAN_CONTEXT:
                        valid_links.append(Link(ref.referenced_context.unwrap()))

            if valid_links and parent is None:
                parent = NonRecordingSpan(valid_links[0].context)

            parent_span_context = set_span_in_context(parent)

            # The OpenTracing API expects time values to be `float` values which
            # represent the number of seconds since the epoch. OpenTelemetry
            # represents time values as nanoseconds since the epoch.
            start_time_ns = start_time
            if start_time_ns is not None:
                start_time_ns = util.time_seconds_to_ns(start_time)

            span = self._otel_tracer.start_span(
                operation_name,
                context=parent_span_context,
                links=valid_links,
                attributes=tags,
                start_time=start_time_ns,
            )

            context = SpanContextShim(span.get_span_context())
            return SpanShim(self, context, span)

        def inject(self, span_context, format: object, carrier: object):
            """Injects ``span_context`` into ``carrier``.

            See base class for more details.

            Args:
                span_context: The ``opentracing.SpanContext`` to inject.
                format: a Python object instance that represents a given
                    carrier format. `format` may be of any type, and `format`
                    equality is defined by Python ``==`` operator.
                carrier: the format-specific carrier object to inject into
            """

            # pylint: disable=redefined-builtin
            # This implementation does not perform the injecting by itself but
            # uses the configured propagators in opentelemetry.propagators.
            # TODO: Support Format.BINARY once it is supported in
            # opentelemetry-python.

            if format not in self._supported_formats:
                raise UnsupportedFormatException

            propagator = get_global_textmap()

            span = span_context.unwrap() if span_context else None
            if isinstance(span, OtelSpanContext):
                span = NonRecordingSpan(span)

            ctx = set_span_in_context(span)
            propagator.inject(carrier, context=ctx)

        def extract(self, format: object, carrier: object):
            """Returns an ``opentracing.SpanContext`` instance extracted from a
            ``carrier``.

            See base class for more details.

            Args:
                format: a Python object instance that represents a given
                    carrier format. ``format`` may be of any type, and ``format``
                    equality is defined by python ``==`` operator.
                carrier: the format-specific carrier object to extract from

            Returns:
                An ``opentracing.SpanContext`` extracted from ``carrier`` or
                ``None`` if no such ``SpanContext`` could be found.
            """

            # pylint: disable=redefined-builtin
            # This implementation does not perform the extracting by itself but
            # uses the configured propagators in opentelemetry.propagators.
            # TODO: Support Format.BINARY once it is supported in
            # opentelemetry-python.
            if format not in self._supported_formats:
                raise UnsupportedFormatException

            propagator = get_global_textmap()
            ctx = propagator.extract(carrier)
            span = get_current_span(ctx)
            if span is not None:
                otel_context = span.get_span_context()
            else:
                otel_context = INVALID_SPAN_CONTEXT

            return SpanContextShim(otel_context)