status.py

# 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.

import enum
import logging
import typing

logger = logging.getLogger(__name__)


class StatusCanonicalCode(enum.Enum):
    """Represents the canonical set of status codes of a finished Span."""

    OK = 0
    """Not an error, returned on success."""

    CANCELLED = 1
    """The operation was cancelled, typically by the caller."""

    UNKNOWN = 2
    """Unknown error.

    For example, this error may be returned when a Status value received from
    another address space belongs to an error space that is not known in this
    address space. Also errors raised by APIs that do not return enough error
    information may be converted to this error.
    """

    INVALID_ARGUMENT = 3
    """The client specified an invalid argument.

    Note that this differs from FAILED_PRECONDITION. INVALID_ARGUMENT indicates
    arguments that are problematic regardless of the state of the system (e.g.,
    a malformed file name).
    """

    DEADLINE_EXCEEDED = 4
    """The deadline expired before the operation could complete.

    For operations that change the state of the system, this error may be
    returned even if the operation has completed successfully. For example, a
    successful response from a server could have been delayed long
    """

    NOT_FOUND = 5
    """Some requested entity (e.g., file or directory) was not found.

    Note to server developers: if a request is denied for an entire class of
    users, such as gradual feature rollout or undocumented whitelist, NOT_FOUND
    may be used. If a request is denied for some users within a class of users,
    such as user-based access control, PERMISSION_DENIED must be used.
    """

    ALREADY_EXISTS = 6
    """The entity that a client attempted to create (e.g., file or directory)
    already exists.
    """

    PERMISSION_DENIED = 7
    """The caller does not have permission to execute the specified operation.

    PERMISSION_DENIED must not be used for rejections caused by exhausting some
    resource (use RESOURCE_EXHAUSTED instead for those errors).
    PERMISSION_DENIED must not be used if the caller can not be identified (use
    UNAUTHENTICATED instead for those errors). This error code does not imply
    the request is valid or the requested entity exists or satisfies other
    pre-conditions.
    """

    RESOURCE_EXHAUSTED = 8
    """Some resource has been exhausted, perhaps a per-user quota, or perhaps
    the entire file system is out of space.
    """

    FAILED_PRECONDITION = 9
    """The operation was rejected because the system is not in a state required
    for the operation's execution.

    For example, the directory to be deleted is non-empty, an rmdir operation
    is applied to a non-directory, etc. Service implementors can use the
    following guidelines to decide between FAILED_PRECONDITION, ABORTED, and
    UNAVAILABLE:

        (a) Use UNAVAILABLE if the client can retry just the failing call.
        (b) Use ABORTED if the client should retry at a higher level (e.g.,
            when a client-specified test-and-set fails, indicating the client
            should restart a read-modify-write sequence).
        (c) Use FAILED_PRECONDITION if the client should not retry until the
            system state has been explicitly fixed.

    E.g., if an "rmdir" fails because the directory is non-empty,
    FAILED_PRECONDITION should be returned since the client should not retry
    unless the files are deleted from the directory.
    """

    ABORTED = 10
    """The operation was aborted, typically due to a concurrency issue such as a
    sequencer check failure or transaction abort.

    See the guidelines above for deciding between FAILED_PRECONDITION, ABORTED,
    and UNAVAILABLE.
    """

    OUT_OF_RANGE = 11
    """The operation was attempted past the valid range.

    E.g., seeking or reading past end-of-file. Unlike INVALID_ARGUMENT, this
    error indicates a problem that may be fixed if the system state changes.
    For example, a 32-bit file system will generate INVALID_ARGUMENT if asked
    to read at an offset that is not in the range [0,2^32-1],but it will
    generate OUT_OF_RANGE if asked to read from an offset past the current file
    size. There is a fair bit of overlap between FAILED_PRECONDITION and
    OUT_OF_RANGE. We recommend using OUT_OF_RANGE (the more specific error)
    when it applies so that callers who are iterating through a space can
    easily look for an OUT_OF_RANGE error to detect when they are done.
    """

    UNIMPLEMENTED = 12
    """The operation is not implemented or is not supported/enabled in this
    service.
    """

    INTERNAL = 13
    """Internal errors.

    This means that some invariants expected by the underlying system have been
    broken. This error code is reserved for serious errors.
    """

    UNAVAILABLE = 14
    """The service is currently unavailable.

    This is most likely a transient condition, which can be corrected by
    retrying with a backoff.  Note that it is not always safe to retry
    non-idempotent operations.
    """

    DATA_LOSS = 15
    """Unrecoverable data loss or corruption."""

    UNAUTHENTICATED = 16
    """The request does not have valid authentication credentials for the
    operation.
    """


class Status:
    """Represents the status of a finished Span.

    Args:
        canonical_code: The canonical status code that describes the result
            status of the operation.
        description: An optional description of the status.
    """

    def __init__(
        self,
        canonical_code: StatusCanonicalCode = StatusCanonicalCode.OK,
        description: typing.Optional[str] = None,
    ):
        self._canonical_code = canonical_code
        self._description = None
        if description is not None and not isinstance(description, str):
            logger.warning("Invalid status description type, expected str")
        else:
            self._description = description

    @property
    def canonical_code(self) -> StatusCanonicalCode:
        """Represents the canonical status code of a finished Span."""
        return self._canonical_code

    @property
    def description(self) -> typing.Optional[str]:
        """Status description"""
        return self._description

    @property
    def is_ok(self) -> bool:
        """Returns false if this represents an error, true otherwise."""
        return self._canonical_code is StatusCanonicalCode.OK