Constants and Exceptions

These two modules sit at Layer 0 — they have zero internal dependencies and form the foundation that every other module builds on.

Constants — sayt2.constants

Three str-based enums define the valid values for field configuration. Using enums (rather than bare strings) gives IDE autocomplete and catches typos at validation time.

class FieldTypeEnum(str, enum.Enum):
    STORED = "stored"
    KEYWORD = "keyword"
    TEXT = "text"
    NGRAM = "ngram"
    NUMERIC = "numeric"
    DATETIME = "datetime"
    BOOLEAN = "boolean"

FieldTypeEnum lists the seven field types. Each value matches the type discriminator on the corresponding BaseField subclass.

class TokenizerEnum(str, enum.Enum):
    DEFAULT = "default"
    EN_STEM = "en_stem"

TokenizerEnum enumerates the built-in tokenisers available for TextField.

class NumericKindEnum(str, enum.Enum):
    I64 = "i64"
    U64 = "u64"
    F64 = "f64"

NumericKindEnum specifies the numeric precision for NumericField — signed 64-bit integer, unsigned 64-bit integer, or 64-bit float.

Exceptions — sayt2.exc

Three custom exceptions provide clear, catchable error signals.

class MalformedFieldSettingError(ValueError):
    """Raised when a field configuration is invalid."""

    pass


class MalformedDatasetSettingError(ValueError):
    """Raised when a DataSet configuration is invalid (e.g. duplicate field names)."""

    pass


class TrackerIsLockedError(RuntimeError):
    """Raised when attempting to acquire a lock that is already held and not expired."""

    pass

Exception	Base class	When it is raised
MalformedFieldSettingError	ValueError	A field definition fails validation (e.g. max_gram < min_gram).
MalformedDatasetSettingError	ValueError	A DataSet configuration is invalid (e.g. duplicate field names).
TrackerIsLockedError	RuntimeError	lock_it() cannot acquire the lock because another process holds it and it has not expired.