Pickle

mail_intake.credentials.pickle

Local filesystem–based credential persistence for Mail Intake.

Summary

This module provides a file-backed implementation of the CredentialStore abstraction using Python's pickle module.

The pickle-based credential store is intended for local development, single-node deployments, and controlled environments where credentials do not need to be shared across processes or machines.

Due to the security and portability risks associated with pickle-based serialization, this implementation is not suitable for distributed or untrusted environments.

Classes

PickleCredentialStore

PickleCredentialStore(path: str)

Bases: CredentialStore[T]

Filesystem-backed credential store using pickle serialization.

This store persists credentials as a pickled object on the local filesystem. It is a simple implementation intended primarily for development, testing, and single-process execution contexts.

Notes

Guarantees:

- Stores credentials on the local filesystem
- Uses pickle for serialization and deserialization
- Does not provide encryption, locking, or concurrency guarantees

Constraints:

- Credential lifecycle management, validation, and refresh logic are explicitly out of scope for this class

Initialize a pickle-backed credential store.

Parameters:

Name	Type	Description	Default
`path`	`str`	Filesystem path where credentials will be stored. The file will be created or overwritten as needed.	required

Functions

clear

clear() -> None

Remove persisted credentials from the local filesystem.

Notes

Lifecycle:

- This method deletes the credential file if it exists and should be treated as an idempotent operation

load

load() -> Optional[T]

Load credentials from the local filesystem.

Returns:

Type	Description
`Optional[T]`	Optional[T]: An instance of type `T` if credentials are present and successfully deserialized; otherwise `None`.

Notes

Guarantees:

- If the credential file does not exist or cannot be successfully deserialized, this method returns ``None``
- The store does not attempt to validate or interpret the returned credentials

save

save(credentials: T) -> None

Persist credentials to the local filesystem.

Parameters:

Name	Type	Description	Default
`credentials`	`T`	The credential object to persist.	required

Notes

Responsibilities:

1	`- Any previously stored credentials at the configured path are overwritten`