Add auto base and auto abstract

CHANGELOG.md

@@ -11,9 +11,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 -
 -
 ### Changed
-
+
+- Create `AutoBase` and `AutoAbstract` classes, some of `Auto` class's logic moved there ([#1114](https://github.com/tinkoff-ai/etna/pull/1114)) 
 - Impose specific order of columns on return value of TSDataset.to_flatten ([#1095](https://github.com/tinkoff-ai/etna/pull/1095))
--
 ### Fixed
 
 - Fix bug in `GaleShapleyFeatureSelectionTransform` with wrong number of remaining features ([#1110](https://github.com/tinkoff-ai/etna/pull/1110))

etna/auto/auto.py

@@ -1,3 +1,5 @@
+from abc import ABC
+from abc import abstractmethod
 from typing import Callable
 from typing import List
 from typing import Optional
@@ -37,8 +39,96 @@ def __call__(self, pipeline: Pipeline) -> None:
         ...
 
 
-class Auto:
-    """Automatic pipeline selection via defined or custom pipeline pool."""
+class AutoAbstract(ABC):
+    """Interface for ``Auto`` object."""
+
+    @abstractmethod
+    def fit(
+        self,
+        ts: TSDataset,
+        timeout: Optional[int] = None,
+        n_trials: Optional[int] = None,
+        initializer: Optional[_Initializer] = None,
+        callback: Optional[_Callback] = None,
+        **optuna_kwargs,
+    ) -> Pipeline:
+        """
+        Start automatic pipeline selection.
+
+        Parameters
+        ----------
+        ts:
+            tsdataset to fit on
+        timeout:
+            timeout for optuna. N.B. this is timeout for each worker
+        n_trials:
+            number of trials for optuna. N.B. this is number of trials for each worker
+        initializer:
+            is called before each pipeline backtest, can be used to initialize loggers
+        callback:
+            is called after each pipeline backtest, can be used to log extra metrics
+        optuna_kwargs:
+            additional kwargs for optuna :py:meth:`optuna.study.Study.optimize`
+        """
+        pass
+
+    @abstractmethod
+    def _init_optuna(self):
+        """Initialize optuna."""
+
+    @abstractmethod
+    def summary(self) -> pd.DataFrame:
+        """Get Auto trials summary."""
+        pass
+
+    @abstractmethod
+    def top_k(self, k: int = 5) -> List[Pipeline]:
+        """
+        Get top k pipelines.
+
+        Parameters
+        ----------
+        k:
+            number of pipelines to return
+        """
+        pass
+
+    @staticmethod
+    @abstractmethod
+    def objective(
+        ts: TSDataset,
+        target_metric: Metric,
+        metric_aggregation: MetricAggregationStatistics,
+        metrics: List[Metric],
+        backtest_params: dict,
+        initializer: Optional[_Initializer] = None,
+        callback: Optional[_Callback] = None,
+    ) -> Callable[[Trial], float]:
+        """
+        Optuna objective wrapper.
+
+        Parameters
+        ----------
+        ts:
+            tsdataset to fit on
+        target_metric:
+            metric to optimize
+        metric_aggregation:
+            aggregation method for per-segment metrics
+        metrics:
+            list of metrics to compute
+        backtest_params:
+            custom parameters for backtest instead of default backtest parameters
+        initializer:
+            is called before each pipeline backtest, can be used to initialize loggers
+        callback:
+            is called after each pipeline backtest, can be used to log extra metrics
+        """
+        pass
+
+
+class AutoBase(AutoAbstract):
+    """Base Class for ``Auto`` and ``Tune``, implementing core logic behind these classes."""
 
     def __init__(
         self,
@@ -47,13 +137,12 @@ def __init__(
         metric_aggregation: MetricAggregationStatistics = "mean",
         backtest_params: Optional[dict] = None,
         experiment_folder: Optional[str] = None,
-        pool: Union[Pool, List[Pipeline]] = Pool.default,
         runner: Optional[AbstractRunner] = None,
         storage: Optional[BaseStorage] = None,
         metrics: Optional[List[Metric]] = None,
     ):
         """
-        Initialize Auto class.
+        Initialize AutoBase class.
 
         Parameters
         ----------
@@ -67,8 +156,6 @@ def __init__(
             custom parameters for backtest instead of default backtest parameters
         experiment_folder:
             folder to store experiment results and name for optuna study
-        pool:
-            pool of pipelines to choose from
         runner:
             runner to use for distributed training
         storage:
@@ -79,12 +166,11 @@ def __init__(
         if target_metric.greater_is_better is None:
             raise ValueError("target_metric.greater_is_better is None")
         self.target_metric = target_metric
-
-        self.metric_aggregation = metric_aggregation
-        self.backtest_params = {} if backtest_params is None else backtest_params
         self.horizon = horizon
+        self.metric_aggregation: MetricAggregationStatistics = metric_aggregation
+        self.backtest_params = {} if backtest_params is None else backtest_params
         self.experiment_folder = experiment_folder
-        self.pool = pool
+
         self.runner = LocalRunner() if runner is None else runner
         self.storage = RDBStorage("sqlite:///etna-auto.db") if storage is None else storage
 
@@ -94,6 +180,87 @@ def __init__(
         self.metrics = metrics
         self._optuna: Optional[Optuna] = None
 
+    def summary(self) -> pd.DataFrame:
+        """Get Auto trials summary.
+
+        Returns
+        -------
+        study_dataframe:
+            dataframe with detailed info on each performed trial
+        """
+        if self._optuna is None:
+            self._optuna = self._init_optuna()
+
+        study = self._optuna.study.get_trials()
+
+        study_params = [
+            {**trial.user_attrs, "pipeline": get_from_params(**trial.user_attrs["pipeline"]), "state": trial.state}
+            for trial in study
+        ]
+
+        return pd.DataFrame(study_params)
+
+    def top_k(self, k: int = 5) -> List[Pipeline]:
+        """
+        Get top k pipelines.
+
+        Parameters
+        ----------
+        k:
+            number of pipelines to return
+        """
+        summary = self.summary()
+        df = summary.sort_values(
+            by=[f"{self.target_metric.name}_{self.metric_aggregation}"],
+            ascending=(not self.target_metric.greater_is_better),
+        )
+        return [pipeline for pipeline in df["pipeline"].values[:k]]  # noqa: C416
+
+
+class Auto(AutoBase):
+    """Automatic pipeline selection via defined or custom pipeline pool."""
+
+    def __init__(
+        self,
+        target_metric: Metric,
+        horizon: int,
+        metric_aggregation: MetricAggregationStatistics = "mean",
+        backtest_params: Optional[dict] = None,
+        experiment_folder: Optional[str] = None,
+        pool: Union[Pool, List[Pipeline]] = Pool.default,
+        runner: Optional[AbstractRunner] = None,
+        storage: Optional[BaseStorage] = None,
+        metrics: Optional[List[Metric]] = None,
+    ):
+        """
+        Initialize Auto class.
+
+        Parameters
+        ----------
+        target_metric:
+            metric to optimize
+        horizon:
+            horizon to forecast for
+        metric_aggregation:
+            aggregation method for per-segment metrics
+        backtest_params:
+            custom parameters for backtest instead of default backtest parameters
+        experiment_folder:
+            folder to store experiment results and name for optuna study
+        pool:
+            pool of pipelines to choose from
+        runner:
+            runner to use for distributed training
+        storage:
+            optuna storage to use
+        metrics:
+            list of metrics to compute
+        """
+        super().__init__(
+            target_metric, horizon, metric_aggregation, backtest_params, experiment_folder, runner, storage, metrics
+        )
+        self.pool = pool
+
     def fit(
         self,
         ts: TSDataset,
@@ -142,53 +309,6 @@ def fit(
 
         return get_from_params(**self._optuna.study.best_trial.user_attrs["pipeline"])
 
-    def _init_optuna(self):
-        """Initialize optuna."""
-        if isinstance(self.pool, Pool):
-            pool: List[Pipeline] = self.pool.value.generate(horizon=self.horizon)
-        else:
-            pool = self.pool
-
-        pool_ = [pipeline.to_dict() for pipeline in pool]
-
-        optuna = Optuna(
-            direction="maximize" if self.target_metric.greater_is_better else "minimize",
-            study_name=self.experiment_folder,
-            storage=self.storage,
-            sampler=ConfigSampler(configs=pool_),
-        )
-        return optuna
-
-    def summary(self) -> pd.DataFrame:
-        """Get Auto trials summary."""
-        if self._optuna is None:
-            self._optuna = self._init_optuna()
-
-        study = self._optuna.study.get_trials()
-
-        study_params = [
-            {**trial.user_attrs, "pipeline": get_from_params(**trial.user_attrs["pipeline"]), "state": trial.state}
-            for trial in study
-        ]
-
-        return pd.DataFrame(study_params)
-
-    def top_k(self, k: int = 5) -> List[Pipeline]:
-        """
-        Get top k pipelines.
-
-        Parameters
-        ----------
-        k:
-            number of pipelines to return
-        """
-        summary = self.summary()
-        df = summary.sort_values(
-            by=[f"{self.target_metric.name}_{self.metric_aggregation}"],
-            ascending=(not self.target_metric.greater_is_better),
-        )
-        return [pipeline for pipeline in df["pipeline"].values[:k]]  # noqa: C416
-
     @staticmethod
     def objective(
         ts: TSDataset,
@@ -243,3 +363,20 @@ def _objective(trial: Trial) -> float:
             return aggregated_metrics[f"{target_metric.name}_{metric_aggregation}"]
 
         return _objective
+
+    def _init_optuna(self):
+        """Initialize optuna."""
+        if isinstance(self.pool, Pool):
+            pool: List[Pipeline] = self.pool.value.generate(horizon=self.horizon)
+        else:
+            pool = self.pool
+
+        pool_ = [pipeline.to_dict() for pipeline in pool]
+
+        optuna = Optuna(
+            direction="maximize" if self.target_metric.greater_is_better else "minimize",
+            study_name=self.experiment_folder,
+            storage=self.storage,
+            sampler=ConfigSampler(configs=pool_),
+        )
+        return optuna