Integrations

Edify ships lightweight integration modules that let you drop a compiled edify.Pattern into the field-validation layers of the frameworks most Python teams actually use. Each integration is an opt-in extra — pip install edify never pulls the framework in, and importing an integration module never imports the framework at module load time. The first helper call resolves the framework lazily; when the extra is missing you get a clean edify.errors.integration.MissingIntegrationDependencyError with the exact install line to run.

Install any one, or all three:

pip install 'edify[pydantic]'
pip install 'edify[fastapi]'
pip install 'edify[django]'
pip install 'edify[all]'

Pydantic

Pydantic integration — validate string fields against an edify Pattern.

Requires the pydantic extra: pip install edify[pydantic]. Importing this module without the framework installed raises ImportError at import time.

Typical usage:

from typing import Annotated
from pydantic import AfterValidator, BaseModel
from edify.integrations.pydantic import pattern_validator
from edify.library import email

class Contact(BaseModel):
    address: Annotated[str, AfterValidator(pattern_validator(email))]

edify.integrations.pydantic.pattern_validator(pattern: Pattern) → Callable[[str], str]

Return a Pydantic-compatible validator callable for pattern.

The returned callable accepts a string and returns it unchanged when the pattern matches; otherwise raises edify.errors.integration.PatternDidNotMatchError (a ValueError subclass) that Pydantic embeds in its ValidationError.

Parameters:

pattern – The edify.Pattern the field must match anywhere in.

FastAPI

FastAPI integration — validate request paths and queries against an edify Pattern.

Requires the fastapi extra: pip install edify[fastapi]. Importing this module without the framework installed raises ImportError at import time.

edify.integrations.fastapi.pattern_path(pattern: Pattern, description: str | None = None) → Path

Return a fastapi.Path value pinned to pattern.

Parameters:

• pattern – The edify.Pattern a path parameter must match anywhere in.

• description – Optional OpenAPI description forwarded to fastapi.Path().

edify.integrations.fastapi.pattern_query(pattern: Pattern, default: str | None = None, description: str | None = None) → Query

Return a fastapi.Query value pinned to pattern.

Parameters:

• pattern – The edify.Pattern a query parameter must match anywhere in.

• default – Optional default value; when None the parameter is required.

• description – Optional OpenAPI description forwarded to fastapi.Query().

Django

Django integration — validate model / form fields against an edify Pattern.

Requires the django extra: pip install edify[django]. Django ships no type information, so the module is loaded through importlib.import_module() and its one used entry point is described by a local Protocol.

edify.integrations.django.pattern_validator(pattern: Pattern, message: str | None = None, code: str = 'invalid') → _RegexValidator

Return a django.core.validators.RegexValidator pinned to pattern.

Parameters:

• pattern – The edify.Pattern a field must match anywhere in.

• message – The error message the validator raises on rejection. Defaults to a message that reproduces the pattern’s regex string.

• code – The Django validation-error code the validator raises on rejection.