prefect.server.schemas.states

State schemas.

State

Bases: StateBaseModel, Generic[R]

Represents the state of a run.

Source code in prefect/server/schemas/states.py

class State(StateBaseModel, Generic[R]):
    """Represents the state of a run."""

    class Config:
        orm_mode = True

    type: StateType
    name: Optional[str] = Field(default=None)
    timestamp: DateTimeTZ = Field(default_factory=lambda: pendulum.now("UTC"))
    message: Optional[str] = Field(default=None, example="Run started")
    data: Optional[Any] = Field(
        default=None,
        description=(
            "Data associated with the state, e.g. a result. "
            "Content must be storable as JSON."
        ),
    )
    state_details: StateDetails = Field(default_factory=StateDetails)

    @classmethod
    def from_orm_without_result(
        cls,
        orm_state: Union[
            "prefect.server.database.orm_models.ORMFlowRunState",
            "prefect.server.database.orm_models.ORMTaskRunState",
        ],
        with_data: Optional[Any] = None,
    ):
        """
        During orchestration, ORM states can be instantiated prior to inserting results
        into the artifact table and the `data` field will not be eagerly loaded. In
        these cases, sqlalchemy will attept to lazily load the the relationship, which
        will fail when called within a synchronous pydantic method.

        This method will construct a `State` object from an ORM model without a loaded
        artifact and attach data passed using the `with_data` argument to the `data`
        field.
        """

        field_keys = cls.schema()["properties"].keys()
        state_data = {
            field: getattr(orm_state, field, None)
            for field in field_keys
            if field != "data"
        }
        state_data["data"] = with_data
        return cls(**state_data)

    @validator("name", always=True)
    def default_name_from_type(cls, v, *, values, **kwargs):
        """If a name is not provided, use the type"""

        # if `type` is not in `values` it means the `type` didn't pass its own
        # validation check and an error will be raised after this function is called
        if v is None and values.get("type"):
            v = " ".join([v.capitalize() for v in values.get("type").value.split("_")])
        return v

    @root_validator
    def default_scheduled_start_time(cls, values):
        """
        TODO: This should throw an error instead of setting a default but is out of
              scope for https://github.com/PrefectHQ/orion/pull/174/ and can be rolled
              into work refactoring state initialization
        """
        if values.get("type") == StateType.SCHEDULED:
            state_details = values.setdefault(
                "state_details", cls.__fields__["state_details"].get_default()
            )
            if not state_details.scheduled_time:
                state_details.scheduled_time = pendulum.now("utc")
        return values

    def is_scheduled(self) -> bool:
        return self.type == StateType.SCHEDULED

    def is_pending(self) -> bool:
        return self.type == StateType.PENDING

    def is_running(self) -> bool:
        return self.type == StateType.RUNNING

    def is_completed(self) -> bool:
        return self.type == StateType.COMPLETED

    def is_failed(self) -> bool:
        return self.type == StateType.FAILED

    def is_crashed(self) -> bool:
        return self.type == StateType.CRASHED

    def is_cancelled(self) -> bool:
        return self.type == StateType.CANCELLED

    def is_final(self) -> bool:
        return self.type in TERMINAL_STATES

    def is_paused(self) -> bool:
        return self.type == StateType.PAUSED

    def copy(self, *, update: dict = None, reset_fields: bool = False, **kwargs):
        """
        Copying API models should return an object that could be inserted into the
        database again. The 'timestamp' is reset using the default factory.
        """
        update = update or {}
        update.setdefault("timestamp", self.__fields__["timestamp"].get_default())
        return super().copy(reset_fields=reset_fields, update=update, **kwargs)

    def result(self, raise_on_failure: bool = True, fetch: Optional[bool] = None):
        # Backwards compatible `result` handling on the server-side schema
        from prefect.states import State

        warnings.warn(
            (
                "`result` is no longer supported by"
                " `prefect.server.schemas.states.State` and will be removed in a future"
                " release. When result retrieval is needed, use `prefect.states.State`."
            ),
            DeprecationWarning,
            stacklevel=2,
        )

        state = State.parse_obj(self)
        return state.result(raise_on_failure=raise_on_failure, fetch=fetch)

    def to_state_create(self):
        # Backwards compatibility for `to_state_create`
        from prefect.client.schemas import State

        warnings.warn(
            (
                "Use of `prefect.server.schemas.states.State` from the client is"
                " deprecated and support will be removed in a future release. Use"
                " `prefect.states.State` instead."
            ),
            DeprecationWarning,
            stacklevel=2,
        )

        state = State.parse_obj(self)
        return state.to_state_create()

    def __repr__(self) -> str:
        """
        Generates a complete state representation appropriate for introspection
        and debugging, including the result:

        `MyCompletedState(message="my message", type=COMPLETED, result=...)`
        """
        from prefect.deprecated.data_documents import DataDocument

        if isinstance(self.data, DataDocument):
            result = self.data.decode()
        else:
            result = self.data

        display = dict(
            message=repr(self.message),
            type=str(self.type.value),
            result=repr(result),
        )

        return f"{self.name}({', '.join(f'{k}={v}' for k, v in display.items())})"

    def __str__(self) -> str:
        """
        Generates a simple state representation appropriate for logging:

        `MyCompletedState("my message", type=COMPLETED)`
        """

        display = []

        if self.message:
            display.append(repr(self.message))

        if self.type.value.lower() != self.name.lower():
            display.append(f"type={self.type.value}")

        return f"{self.name}({', '.join(display)})"

    def __hash__(self) -> int:
        return hash(
            (
                getattr(self.state_details, "flow_run_id", None),
                getattr(self.state_details, "task_run_id", None),
                self.timestamp,
                self.type,
            )
        )

from_orm_without_result classmethod

During orchestration, ORM states can be instantiated prior to inserting results into the artifact table and the data field will not be eagerly loaded. In these cases, sqlalchemy will attept to lazily load the the relationship, which will fail when called within a synchronous pydantic method.

This method will construct a State object from an ORM model without a loaded artifact and attach data passed using the with_data argument to the data field.

Source code in prefect/server/schemas/states.py

@classmethod
def from_orm_without_result(
    cls,
    orm_state: Union[
        "prefect.server.database.orm_models.ORMFlowRunState",
        "prefect.server.database.orm_models.ORMTaskRunState",
    ],
    with_data: Optional[Any] = None,
):
    """
    During orchestration, ORM states can be instantiated prior to inserting results
    into the artifact table and the `data` field will not be eagerly loaded. In
    these cases, sqlalchemy will attept to lazily load the the relationship, which
    will fail when called within a synchronous pydantic method.

    This method will construct a `State` object from an ORM model without a loaded
    artifact and attach data passed using the `with_data` argument to the `data`
    field.
    """

    field_keys = cls.schema()["properties"].keys()
    state_data = {
        field: getattr(orm_state, field, None)
        for field in field_keys
        if field != "data"
    }
    state_data["data"] = with_data
    return cls(**state_data)

StateBaseModel

Bases: IDBaseModel

Source code in prefect/server/schemas/states.py

class StateBaseModel(IDBaseModel):
    def orm_dict(
        self, *args, shallow: bool = False, json_compatible: bool = False, **kwargs
    ) -> dict:
        """
        This method is used as a convenience method for constructing fixtues by first
        building a `State` schema object and converting it into an ORM-compatible
        format. Because the `data` field is not writable on ORM states, this method
        omits the `data` field entirely for the purposes of constructing an ORM model.
        If state data is required, an artifact must be created separately.
        """

        schema_dict = self.dict(
            *args, shallow=shallow, json_compatible=json_compatible, **kwargs
        )
        # remove the data field in order to construct a state ORM model
        schema_dict.pop("data", None)
        return schema_dict

StateType

Bases: AutoEnum

Enumeration of state types.

Source code in prefect/server/schemas/states.py

class StateType(AutoEnum):
    """Enumeration of state types."""

    SCHEDULED = AutoEnum.auto()
    PENDING = AutoEnum.auto()
    RUNNING = AutoEnum.auto()
    COMPLETED = AutoEnum.auto()
    FAILED = AutoEnum.auto()
    CANCELLED = AutoEnum.auto()
    CRASHED = AutoEnum.auto()
    PAUSED = AutoEnum.auto()
    CANCELLING = AutoEnum.auto()

AwaitingRetry

Convenience function for creating AwaitingRetry states.

Returns:

Name	Type	Description
State	State	a AwaitingRetry state

Source code in prefect/server/schemas/states.py

def AwaitingRetry(
    scheduled_time: datetime.datetime = None, cls: Type[State] = State, **kwargs
) -> State:
    """Convenience function for creating `AwaitingRetry` states.

    Returns:
        State: a AwaitingRetry state
    """
    return Scheduled(
        cls=cls, scheduled_time=scheduled_time, name="AwaitingRetry", **kwargs
    )

Cancelled

Convenience function for creating Cancelled states.

Returns:

Name	Type	Description
State	State	a Cancelled state

Source code in prefect/server/schemas/states.py

def Cancelled(cls: Type[State] = State, **kwargs) -> State:
    """Convenience function for creating `Cancelled` states.

    Returns:
        State: a Cancelled state
    """
    return cls(type=StateType.CANCELLED, **kwargs)

Cancelling

Convenience function for creating Cancelling states.

Returns:

Name	Type	Description
State	State	a Cancelling state

Source code in prefect/server/schemas/states.py

def Cancelling(cls: Type[State] = State, **kwargs) -> State:
    """Convenience function for creating `Cancelling` states.

    Returns:
        State: a Cancelling state
    """
    return cls(type=StateType.CANCELLING, **kwargs)

Completed

Convenience function for creating Completed states.

Returns:

Name	Type	Description
State	State	a Completed state

Source code in prefect/server/schemas/states.py

def Completed(cls: Type[State] = State, **kwargs) -> State:
    """Convenience function for creating `Completed` states.

    Returns:
        State: a Completed state
    """
    return cls(type=StateType.COMPLETED, **kwargs)

Crashed

Convenience function for creating Crashed states.

Returns:

Name	Type	Description
State	State	a Crashed state

Source code in prefect/server/schemas/states.py

def Crashed(cls: Type[State] = State, **kwargs) -> State:
    """Convenience function for creating `Crashed` states.

    Returns:
        State: a Crashed state
    """
    return cls(type=StateType.CRASHED, **kwargs)

Failed

Convenience function for creating Failed states.

Returns:

Name	Type	Description
State	State	a Failed state

Source code in prefect/server/schemas/states.py

def Failed(cls: Type[State] = State, **kwargs) -> State:
    """Convenience function for creating `Failed` states.

    Returns:
        State: a Failed state
    """
    return cls(type=StateType.FAILED, **kwargs)

Late

Convenience function for creating Late states.

Returns:

Name	Type	Description
State	State	a Late state

Source code in prefect/server/schemas/states.py

def Late(
    scheduled_time: datetime.datetime = None, cls: Type[State] = State, **kwargs
) -> State:
    """Convenience function for creating `Late` states.

    Returns:
        State: a Late state
    """
    return Scheduled(cls=cls, scheduled_time=scheduled_time, name="Late", **kwargs)

Paused

Convenience function for creating Paused states.

Returns:

Name	Type	Description
State	State	a Paused state

Source code in prefect/server/schemas/states.py

def Paused(
    cls: Type[State] = State,
    timeout_seconds: int = None,
    pause_expiration_time: datetime.datetime = None,
    reschedule: bool = False,
    pause_key: str = None,
    **kwargs,
) -> State:
    """Convenience function for creating `Paused` states.

    Returns:
        State: a Paused state
    """
    state_details = StateDetails.parse_obj(kwargs.pop("state_details", {}))

    if state_details.pause_timeout:
        raise ValueError("An extra pause timeout was provided in state_details")

    if pause_expiration_time is not None and timeout_seconds is not None:
        raise ValueError(
            "Cannot supply both a pause_expiration_time and timeout_seconds"
        )

    if pause_expiration_time is None and timeout_seconds is None:
        pass
    else:
        state_details.pause_timeout = pause_expiration_time or (
            pendulum.now("UTC") + pendulum.Duration(seconds=timeout_seconds)
        )

    state_details.pause_reschedule = reschedule
    state_details.pause_key = pause_key

    return cls(type=StateType.PAUSED, state_details=state_details, **kwargs)

Pending

Convenience function for creating Pending states.

Returns:

Name	Type	Description
State	State	a Pending state

Source code in prefect/server/schemas/states.py

def Pending(cls: Type[State] = State, **kwargs) -> State:
    """Convenience function for creating `Pending` states.

    Returns:
        State: a Pending state
    """
    return cls(type=StateType.PENDING, **kwargs)

Retrying

Convenience function for creating Retrying states.

Returns:

Name	Type	Description
State	State	a Retrying state

Source code in prefect/server/schemas/states.py

def Retrying(cls: Type[State] = State, **kwargs) -> State:
    """Convenience function for creating `Retrying` states.

    Returns:
        State: a Retrying state
    """
    return cls(type=StateType.RUNNING, name="Retrying", **kwargs)

Running

Convenience function for creating Running states.

Returns:

Name	Type	Description
State	State	a Running state

Source code in prefect/server/schemas/states.py

def Running(cls: Type[State] = State, **kwargs) -> State:
    """Convenience function for creating `Running` states.

    Returns:
        State: a Running state
    """
    return cls(type=StateType.RUNNING, **kwargs)

Scheduled

Convenience function for creating Scheduled states.

Returns:

Name	Type	Description
State	State	a Scheduled state

Source code in prefect/server/schemas/states.py

def Scheduled(
    scheduled_time: datetime.datetime = None, cls: Type[State] = State, **kwargs
) -> State:
    """Convenience function for creating `Scheduled` states.

    Returns:
        State: a Scheduled state
    """
    # NOTE: `scheduled_time` must come first for backwards compatibility

    state_details = StateDetails.parse_obj(kwargs.pop("state_details", {}))
    if scheduled_time is None:
        scheduled_time = pendulum.now("UTC")
    elif state_details.scheduled_time:
        raise ValueError("An extra scheduled_time was provided in state_details")
    state_details.scheduled_time = scheduled_time

    return cls(type=StateType.SCHEDULED, state_details=state_details, **kwargs)