Control config changes

Config flags can be set on a container and inherited by its children. The default for both flags is off.

Read-only

OmegaConf.set_readonly(cfg, True) prevents modification. Use read_write() for a scoped update without leaving the config writable afterward:

>>> from omegaconf import OmegaConf, read_write
>>> cfg = OmegaConf.create({"port": 80})
>>> OmegaConf.set_readonly(cfg, True)
>>> with read_write(cfg):
...     cfg.port = 8080
>>> cfg.port
8080
>>> OmegaConf.is_readonly(cfg)
True

Struct

OmegaConf.set_struct(cfg, True) prevents adding unknown keys. Existing keys remain writable unless the config is also read-only. Use open_dict() for a scoped addition:

>>> from omegaconf import open_dict
>>> cfg = OmegaConf.create({"port": 80})
>>> OmegaConf.set_struct(cfg, True)
>>> with open_dict(cfg):
...     cfg.host = "localhost"
>>> cfg.host
'localhost'
>>> OmegaConf.is_struct(cfg)
True

Frozen structured config classes also produce read-only config values. Use the Python API for set_readonly, set_struct, and the context managers.