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- """runid util."""
- import os
- import random
- import secrets
- from string import ascii_lowercase, digits
- _ID_CHARS = f"{ascii_lowercase}{digits}"
- # Create a dedicated Random instance with its own state so it
- # is not affected by global random.seed() calls
- _random = random.Random()
- # Reset the random number generator on forking a new process to avoid multiple processes using the same seed.
- # The `random` module basically does this internally for python's global random state.
- # This is only necessary on platforms that support the `fork` multiprocessing start method (e.g. POSIX).
- if hasattr(os, "fork"):
- os.register_at_fork(after_in_child=_random.seed)
- def generate_id(length: int = 8) -> str:
- """Generate a random base-36 string of `length` digits."""
- # There are ~2.8T base-36 8-digit strings. If we generate 210k ids,
- # we'll have a ~1% chance of collision.
- return "".join(secrets.choice(_ID_CHARS) for _ in range(length))
- def generate_fast_id(length: int = 8) -> str:
- """Faster alternative to `generate_id` if cryptographic strength isn't needed.
- In local testing at the time of implementation, this is ~30-50x faster than
- `generate_id` when generating 128-character IDs.
- Uses a dedicated Random instance to avoid being affected by global
- random.seed() calls from user code or libraries.
- """
- return "".join(_random.choices(_ID_CHARS, k=length))
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