Parameters versioning

Automatic parameters versioning

Parameters versioning is automatic when the MlflowNodeHook is added to the hook list of the ProjectContext. The mlflow.yml configuration file has a parameter called flatten_dict_params which enables to log as distinct parameters the (key, value) pairs of a ```Dict`` parameter.

You do not need any additional configuration to benefit from parameters versioning.

How does MlflowNodeHook operates under the hood?

The medium post which introduces hooks explains in detail the differents execution steps Kedro executes when the user calls the kedro run command.

The MlflowNodeHook registers the parameters before each node (entry point number 3 on above picture) by calling mlflow.log_parameter(param_name, param_value) on each parameters of the node.

Frequently Asked Questions

Will parameters be recorded if the pipeline fails during execution?

The parameters are registered node by node (and not in a single batch at the beginning of the execution). If the pipeline fails in the middle of its execution, the parameters of the nodes who have been run will be recorded, but not the parameters of non executed nodes.

How are parameters detected by the plugin?

The hook detects parameters through their prefix params: or the value parameters. These are the reserved keywords used by Kedro to define parameters in the file(s).

How can I register a parameter if I use a TemplatedConfigLoader?

If you use a TemplatedConfigLoader to enable dynamic parameters contruction at runtime or dependency between configuration files, and if we assume your src/<project-name>/ file looks like:

from kedro.config import TemplatedConfigLoader  # new import
from datetime import date

class ProjectContext(KedroContext):
    def _create_config_loader(self, conf_paths: Iterable[str]) -> TemplatedConfigLoader:
        return TemplatedConfigLoader(
            globals_pattern="*globals.yml",  # read the globals dictionary from project config
            globals_dict={  # extra keys to add to the globals dictionary, take precedence over globals_pattern

Then you need to add this entry in your conf/<env>/parameters to ensure that the parameter will be properly recorded:

execution_date: ${execution_date}