Module pyquaca.cache

Cache class for caching query results.

Classes

class Cache (cache_dir: str, file_extension: str = '')

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class Cache:
    """Cache class for caching query results."""

    def __init__(self, cache_dir: str, file_extension: str = "") -> None:
        self.cache_dir = cache_dir
        self.file_extension = file_extension
        # Create the cache directory if it does not exist
        Path(self.cache_dir).mkdir(parents=True, exist_ok=True)
        self.logger = logging.getLogger("Cache")

    def retrieve(self, key: str) -> None | str:
        """
        Retrieve data from the cache.

        Args:
            key (str): The cache key to lookup.

        Returns:
            the data string if it is found in the cache, None otherwise.
        """
        full_path = os.path.join(self.cache_dir, key + self.file_extension)
        try:
            with open(full_path, "r", encoding="utf-8") as cache_file:
                return cache_file.read()
        except (FileNotFoundError, PermissionError, IOError) as e:
            self.logger.error("Could not read from cache %s", e)
        return None

    def store(self, key: str, value: Any) -> bool:
        """
        Store data in the cache.

        Args:
            key (str): The key string.
            value (str): The data to store.

        Returns:
            True if the data is successfully stored, False otherwise.
        """
        if not key or len(key) < 1:
            self.logger.error("Invalid key")
            return False
        full_path = os.path.join(self.cache_dir, key + self.file_extension)
        try:
            with open(full_path, "w", encoding="utf-8") as cache_file:
                cache_file.write(value)
            return True
        except (PermissionError, IOError) as e:
            self.logger.error("Could not write to cache %s", e)
        return False

Cache class for caching query results.

Subclasses

• JSONCache

Methods

def retrieve(self, key: str) ‑> str | None

Expand source code

def retrieve(self, key: str) -> None | str:
    """
    Retrieve data from the cache.

    Args:
        key (str): The cache key to lookup.

    Returns:
        the data string if it is found in the cache, None otherwise.
    """
    full_path = os.path.join(self.cache_dir, key + self.file_extension)
    try:
        with open(full_path, "r", encoding="utf-8") as cache_file:
            return cache_file.read()
    except (FileNotFoundError, PermissionError, IOError) as e:
        self.logger.error("Could not read from cache %s", e)
    return None

Retrieve data from the cache.

Args

key : str

The cache key to lookup.

Returns

the data string if it is found in the cache, None otherwise.

def store(self, key: str, value: Any) ‑> bool

Expand source code

def store(self, key: str, value: Any) -> bool:
    """
    Store data in the cache.

    Args:
        key (str): The key string.
        value (str): The data to store.

    Returns:
        True if the data is successfully stored, False otherwise.
    """
    if not key or len(key) < 1:
        self.logger.error("Invalid key")
        return False
    full_path = os.path.join(self.cache_dir, key + self.file_extension)
    try:
        with open(full_path, "w", encoding="utf-8") as cache_file:
            cache_file.write(value)
        return True
    except (PermissionError, IOError) as e:
        self.logger.error("Could not write to cache %s", e)
    return False

Store data in the cache.

Args

key : str

The key string.

value : str

The data to store.

Returns

True if the data is successfully stored, False otherwise.