feat: Adds the /explore endpoint to the v1 API (#20399)

* feat: Adds the /explore endpoint to the v1 API

* Fixes pylint errors

* Fixes tests

* Changes the tests logic

* Removes ABC reference

* Improves indentation

* Addresses review comments

* Rebases code

* Improves dataset and slice assertions

* Fixes tests

* Removes schema and table name assertions

* Removes fixed IDs

* Fixes datasource ID

superset/explore/api.py

@@ -0,0 +1,137 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you 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 logging
+
+from flask import g, request, Response
+from flask_appbuilder.api import BaseApi, expose, protect, safe
+
+from superset.charts.commands.exceptions import ChartNotFoundError
+from superset.constants import MODEL_API_RW_METHOD_PERMISSION_MAP, RouteMethod
+from superset.explore.commands.get import GetExploreCommand
+from superset.explore.commands.parameters import CommandParameters
+from superset.explore.exceptions import DatasetAccessDeniedError, WrongEndpointError
+from superset.explore.permalink.exceptions import ExplorePermalinkGetFailedError
+from superset.explore.schemas import ExploreContextSchema
+from superset.extensions import event_logger
+from superset.temporary_cache.commands.exceptions import (
+    TemporaryCacheAccessDeniedError,
+    TemporaryCacheResourceNotFoundError,
+)
+
+logger = logging.getLogger(__name__)
+
+
+class ExploreRestApi(BaseApi):
+    method_permission_name = MODEL_API_RW_METHOD_PERMISSION_MAP
+    include_route_methods = {RouteMethod.GET}
+    allow_browser_login = True
+    class_permission_name = "Explore"
+    resource_name = "explore"
+    openapi_spec_tag = "Explore"
+    openapi_spec_component_schemas = (ExploreContextSchema,)
+
+    @expose("/", methods=["GET"])
+    @protect()
+    @safe
+    @event_logger.log_this_with_context(
+        action=lambda self, *args, **kwargs: f"{self.__class__.__name__}.get",
+        log_to_statsd=True,
+    )
+    def get(self) -> Response:
+        """Assembles Explore related information (form_data, slice, dataset)
+         in a single endpoint.
+        ---
+        get:
+          summary: >-
+            Assembles Explore related information (form_data, slice, dataset)
+             in a single endpoint.
+          description: >-
+            Assembles Explore related information (form_data, slice, dataset)
+             in a single endpoint.<br/><br/>
+            The information can be assembled from:<br/>
+            - The cache using a form_data_key<br/>
+            - The metadata database using a permalink_key<br/>
+            - Build from scratch using dataset or slice identifiers.
+          parameters:
+          - in: query
+            schema:
+              type: string
+            name: form_data_key
+          - in: query
+            schema:
+              type: string
+            name: permalink_key
+          - in: query
+            schema:
+              type: integer
+            name: slice_id
+          - in: query
+            schema:
+              type: integer
+            name: dataset_id
+          - in: query
+            schema:
+              type: string
+            name: dataset_type
+          responses:
+            200:
+              description: Returns the initial context.
+              content:
+                application/json:
+                  schema:
+                    $ref: '#/components/schemas/ExploreContextSchema'
+            400:
+              $ref: '#/components/responses/400'
+            401:
+              $ref: '#/components/responses/401'
+            404:
+              $ref: '#/components/responses/404'
+            422:
+              $ref: '#/components/responses/422'
+            500:
+              $ref: '#/components/responses/500'
+        """
+        try:
+            params = CommandParameters(
+                actor=g.user,
+                permalink_key=request.args.get("permalink_key", type=str),
+                form_data_key=request.args.get("form_data_key", type=str),
+                dataset_id=request.args.get("dataset_id", type=int),
+                dataset_type=request.args.get("dataset_type", type=str),
+                slice_id=request.args.get("slice_id", type=int),
+            )
+            result = GetExploreCommand(params).run()
+            if not result:
+                return self.response_404()
+            return self.response(200, result=result)
+        except ValueError as ex:
+            return self.response(400, message=str(ex))
+        except DatasetAccessDeniedError as ex:
+            return self.response(
+                403,
+                message=ex.message,
+                dataset_id=ex.dataset_id,
+                dataset_type=ex.dataset_type,
+            )
+        except (ChartNotFoundError, ExplorePermalinkGetFailedError) as ex:
+            return self.response(404, message=str(ex))
+        except WrongEndpointError as ex:
+            return self.response(302, redirect=ex.redirect)
+        except TemporaryCacheAccessDeniedError as ex:
+            return self.response(403, message=str(ex))
+        except TemporaryCacheResourceNotFoundError as ex:
+            return self.response(404, message=str(ex))

superset/explore/commands/__init__.py

@@ -0,0 +1,16 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you 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.

superset/explore/commands/get.py

@@ -0,0 +1,171 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you 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 logging
+from abc import ABC
+from typing import Any, cast, Dict, Optional
+
+import simplejson as json
+from flask import current_app as app
+from flask_babel import gettext as __, lazy_gettext as _
+from sqlalchemy.exc import SQLAlchemyError
+
+from superset import db, security_manager
+from superset.commands.base import BaseCommand
+from superset.connectors.base.models import BaseDatasource
+from superset.connectors.sqla.models import SqlaTable
+from superset.datasets.commands.exceptions import DatasetNotFoundError
+from superset.datasource.dao import DatasourceDAO
+from superset.exceptions import SupersetException
+from superset.explore.commands.parameters import CommandParameters
+from superset.explore.exceptions import DatasetAccessDeniedError, WrongEndpointError
+from superset.explore.form_data.commands.get import GetFormDataCommand
+from superset.explore.form_data.commands.parameters import (
+    CommandParameters as FormDataCommandParameters,
+)
+from superset.explore.permalink.commands.get import GetExplorePermalinkCommand
+from superset.explore.permalink.exceptions import ExplorePermalinkGetFailedError
+from superset.models.sql_lab import Query
+from superset.utils import core as utils
+from superset.views.utils import (
+    get_datasource_info,
+    get_form_data,
+    sanitize_datasource_data,
+)
+
+logger = logging.getLogger(__name__)
+
+
+class GetExploreCommand(BaseCommand, ABC):
+    def __init__(
+        self,
+        params: CommandParameters,
+    ) -> None:
+        self._actor = params.actor
+        self._permalink_key = params.permalink_key
+        self._form_data_key = params.form_data_key
+        self._dataset_id = params.dataset_id
+        self._dataset_type = params.dataset_type
+        self._slice_id = params.slice_id
+
+    # pylint: disable=too-many-locals,too-many-branches,too-many-statements
+    def run(self) -> Optional[Dict[str, Any]]:
+        initial_form_data = {}
+
+        if self._permalink_key is not None:
+            command = GetExplorePermalinkCommand(self._actor, self._permalink_key)
+            permalink_value = command.run()
+            if not permalink_value:
+                raise ExplorePermalinkGetFailedError()
+            state = permalink_value["state"]
+            initial_form_data = state["formData"]
+            url_params = state.get("urlParams")
+            if url_params:
+                initial_form_data["url_params"] = dict(url_params)
+        elif self._form_data_key:
+            parameters = FormDataCommandParameters(
+                actor=self._actor, key=self._form_data_key
+            )
+            value = GetFormDataCommand(parameters).run()
+            initial_form_data = json.loads(value) if value else {}
+
+        message = None
+
+        if not initial_form_data:
+            if self._slice_id:
+                initial_form_data["slice_id"] = self._slice_id
+                if self._form_data_key:
+                    message = _(
+                        "Form data not found in cache, reverting to chart metadata."
+                    )
+            elif self._dataset_id:
+                initial_form_data["datasource"] = f"{self._dataset_id}__table"
+                if self._form_data_key:
+                    message = _(
+                        "Form data not found in cache, reverting to dataset metadata."
+                    )
+
+        form_data, slc = get_form_data(
+            use_slice_data=True, initial_form_data=initial_form_data
+        )
+        try:
+            self._dataset_id, self._dataset_type = get_datasource_info(
+                self._dataset_id, self._dataset_type, form_data
+            )
+        except SupersetException:
+            self._dataset_id = None
+            # fallback unkonw datasource to table type
+            self._dataset_type = SqlaTable.type
+
+        dataset: Optional[BaseDatasource] = None
+        if self._dataset_id is not None:
+            try:
+                dataset = DatasourceDAO.get_datasource(
+                    db.session, cast(str, self._dataset_type), self._dataset_id
+                )
+            except DatasetNotFoundError:
+                pass
+        dataset_name = dataset.name if dataset else _("[Missing Dataset]")
+
+        if dataset:
+            if app.config["ENABLE_ACCESS_REQUEST"] and (
+                not security_manager.can_access_datasource(dataset)
+            ):
+                message = __(security_manager.get_datasource_access_error_msg(dataset))
+                raise DatasetAccessDeniedError(
+                    message=message,
+                    dataset_type=self._dataset_type,
+                    dataset_id=self._dataset_id,
+                )
+
+        viz_type = form_data.get("viz_type")
+        if not viz_type and dataset and dataset.default_endpoint:
+            raise WrongEndpointError(redirect=dataset.default_endpoint)
+
+        form_data["datasource"] = (
+            str(self._dataset_id) + "__" + cast(str, self._dataset_type)
+        )
+
+        # On explore, merge legacy and extra filters into the form data
+        utils.convert_legacy_filters_into_adhoc(form_data)
+        utils.merge_extra_filters(form_data)
+
+        dummy_dataset_data: Dict[str, Any] = {
+            "type": self._dataset_type,
+            "name": dataset_name,
+            "columns": [],
+            "metrics": [],
+            "database": {"id": 0, "backend": ""},
+        }
+        try:
+            dataset_data = dataset.data if dataset else dummy_dataset_data
+        except (SupersetException, SQLAlchemyError):
+            dataset_data = dummy_dataset_data
+
+        if dataset:
+            dataset_data["owners"] = dataset.owners_data
+            if isinstance(dataset, Query):
+                dataset_data["columns"] = dataset.columns
+
+        return {
+            "dataset": sanitize_datasource_data(dataset_data),
+            "form_data": form_data,
+            "slice": slc.data if slc else None,
+            "message": message,
+        }
+
+    def validate(self) -> None:
+        pass

superset/explore/commands/parameters.py

@@ -0,0 +1,30 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you 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.
+from dataclasses import dataclass
+from typing import Optional
+
+from flask_appbuilder.security.sqla.models import User
+
+
+@dataclass
+class CommandParameters:
+    actor: User
+    permalink_key: Optional[str]
+    form_data_key: Optional[str]
+    dataset_id: Optional[int]
+    dataset_type: Optional[str]
+    slice_id: Optional[int]

superset/explore/exceptions.py

@@ -0,0 +1,35 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you 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.
+from typing import Optional
+
+from superset.commands.exceptions import CommandException, ForbiddenError
+
+
+class DatasetAccessDeniedError(ForbiddenError):
+    def __init__(
+        self, message: str, dataset_id: Optional[int], dataset_type: Optional[str]
+    ) -> None:
+        self.message = message
+        self.dataset_id = dataset_id
+        self.dataset_type = dataset_type
+        super().__init__(self.message)
+
+
+class WrongEndpointError(CommandException):
+    def __init__(self, redirect: str) -> None:
+        self.redirect = redirect
+        super().__init__()