ROS parameter store

NOTE: I no longer work in the field of robotics, this is not maintained. But hopefully the ideas and techniques presented here might be of use to you. Or the software itself might even still work!

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Implements parameter store to file. Inspired by mongodb_store but designed to be simpler and more reliable to power failures. The API is designed to be similar to a subset of mongodb_store.

File format

The file format used both for default values and the persisted data is YAML, but slightly different than what mongodb_store uses. The keys are the parameter names and the value the parameter value. You should not use YAML dictionaries to represent namespaces. For example:

/my_parameter_in_root_ns: 2
/namespace/my_list_parameter:
  - {some_key: some_value}
  - 42

Parameters

This node has two mandatory parameters:

• ~defaults_path (string) - Path to directory containing default YAML files that should be loaded
• ~save_path (string) - Path to file that will be used to store parameters to.

Services

• save_param (ros_parameter_store_msgs/SaveParam) - Save a single parameter, reading the current value from the parameter server. Always use absolute paths for the parameter name to ensure consistency even if this node runs in a namespace.