superset/common/utils.py

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# 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
#
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# 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 typing import Any, Dict, Optional

from flask_caching import Cache
from pandas import DataFrame

from superset import app
from superset.constants import CacheRegion
from superset.exceptions import CacheLoadError
from superset.extensions import cache_manager
from superset.models.helpers import QueryResult
from superset.stats_logger import BaseStatsLogger
from superset.utils.cache import set_and_log_cache
from superset.utils.core import error_msg_from_exception, get_stacktrace, QueryStatus

config = app.config
stats_logger: BaseStatsLogger = config["STATS_LOGGER"]
logger = logging.getLogger(__name__)

_cache: Dict[CacheRegion, Cache] = {
    CacheRegion.DEFAULT: cache_manager.cache,
    CacheRegion.DATA: cache_manager.data_cache,
}


class QueryCacheManager:
    """
    Class for manage query-cache getting and setting
    """

    # pylint: disable=too-many-instance-attributes,too-many-arguments
    def __init__(
        self,
        df: DataFrame = DataFrame(),
        query: str = "",
        annotation_data: Optional[Dict[str, Any]] = None,
        status: Optional[str] = None,
        error_message: Optional[str] = None,
        is_loaded: bool = False,
        stacktrace: Optional[str] = None,
        is_cached: Optional[bool] = None,
        cache_dttm: Optional[str] = None,
        cache_value: Optional[Dict[str, Any]] = None,
    ) -> None:
        self.df = df
        self.query = query
        self.annotation_data = {} if annotation_data is None else annotation_data
        self.status = status
        self.error_message = error_message

        self.is_loaded = is_loaded
        self.stacktrace = stacktrace
        self.is_cached = is_cached
        self.cache_dttm = cache_dttm
        self.cache_value = cache_value

    # pylint: disable=too-many-arguments
    def set_query_result(
        self,
        key: str,
        query_result: QueryResult,
        annotation_data: Optional[Dict[str, Any]] = None,
        force_query: Optional[bool] = False,
        timeout: Optional[int] = None,
        datasource_uid: Optional[str] = None,
        region: CacheRegion = CacheRegion.DEFAULT,
    ) -> None:
        """
        Set dataframe of query-result to specific cache region
        """
        try:
            self.status = query_result.status
            self.query = query_result.query
            self.error_message = query_result.error_message
            self.df = query_result.df
            self.annotation_data = {} if annotation_data is None else annotation_data

            if self.status != QueryStatus.FAILED:
                stats_logger.incr("loaded_from_source")
                if not force_query:
                    stats_logger.incr("loaded_from_source_without_force")
                self.is_loaded = True

            value = {
                "df": self.df,
                "query": self.query,
                "annotation_data": self.annotation_data,
            }
            if self.is_loaded and key and self.status != QueryStatus.FAILED:
                self.set(
                    key=key,
                    value=value,
                    timeout=timeout,
                    datasource_uid=datasource_uid,
                    region=region,
                )
        except Exception as ex:  # pylint: disable=broad-except
            logger.exception(ex)
            if not self.error_message:
                self.error_message = str(ex)
            self.status = QueryStatus.FAILED
            self.stacktrace = get_stacktrace()

    @classmethod
    def get(
        cls,
        key: Optional[str],
        region: CacheRegion = CacheRegion.DEFAULT,
        force_query: Optional[bool] = False,
        force_cached: Optional[bool] = False,
    ) -> "QueryCacheManager":
        """
        Initialize QueryCacheManager by query-cache key
        """
        query_cache = cls()
        if not key or not _cache[region] or force_query:
            return query_cache

        cache_value = _cache[region].get(key)
        if cache_value:
            logger.info("Cache key: %s", key)
            stats_logger.incr("loading_from_cache")
            try:
                query_cache.df = cache_value["df"]
                query_cache.query = cache_value["query"]
                query_cache.annotation_data = cache_value.get("annotation_data", {})
                query_cache.status = QueryStatus.SUCCESS
                query_cache.is_loaded = True
                query_cache.is_cached = cache_value is not None
                query_cache.cache_dttm = (
                    cache_value["dttm"] if cache_value is not None else None
                )
                query_cache.cache_value = cache_value
                stats_logger.incr("loaded_from_cache")
            except KeyError as ex:
                logger.exception(ex)
                logger.error(
                    "Error reading cache: %s",
                    error_msg_from_exception(ex),
                    exc_info=True,
                )
            logger.info("Serving from cache")

        if force_cached and not query_cache.is_loaded:
            logger.warning(
                "force_cached (QueryContext): value not found for key %s", key
            )
            raise CacheLoadError("Error loading data from cache")
        return query_cache

    @staticmethod
    def set(
        key: Optional[str],
        value: Dict[str, Any],
        timeout: Optional[int] = None,
        datasource_uid: Optional[str] = None,
        region: CacheRegion = CacheRegion.DEFAULT,
    ) -> None:
        """
        set value to specify cache region, proxy for `set_and_log_cache`
        """
        if key:
            set_and_log_cache(_cache[region], key, value, timeout, datasource_uid)