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ROS2: How to query all parameters from RViz using Python

The following script will query all parameters from RViz (/rviz/get_parameters) using Python.

This is achieved by first listing all parameters, then querying and printing them.

#!/usr/bin/env python3

import rclpy
from rclpy.node import Node
from rcl_interfaces.srv import GetParameters, ListParameters

class RvizParamQuery(Node):
    def __init__(self):
        super().__init__('rviz_param_query')
        self.get_client = self.create_client(GetParameters, '/rviz2/get_parameters')
        self.list_client = self.create_client(ListParameters, '/rviz2/list_parameters')
        
        # Wait for services
        while not all([
            self.get_client.wait_for_service(timeout_sec=1.0),
            self.list_client.wait_for_service(timeout_sec=1.0)
        ]):
            self.get_logger().info('Services not available, waiting...')

    def list_all_parameters(self):
        request = ListParameters.Request()
        future = self.list_client.call_async(request)
        rclpy.spin_until_future_complete(self, future)
        return future.result().result.names

    def query_parameters(self, param_names):
        request = GetParameters.Request()
        request.names = param_names
        future = self.get_client.call_async(request)
        rclpy.spin_until_future_complete(self, future)
        return future.result()

def main():
    rclpy.init()
    param_query = RvizParamQuery()
    
    # Get list of all parameters
    param_names = param_query.list_all_parameters()
    
    # Query values for all parameters
    result = param_query.query_parameters(param_names)
    
    # Display results
    for name, value in zip(param_names, result.values):
        if value.type == 1:  # PARAMETER_BOOL
            val = value.bool_value
        elif value.type == 2:  # PARAMETER_INTEGER
            val = value.integer_value
        elif value.type == 3:  # PARAMETER_DOUBLE
            val = value.double_value
        elif value.type == 4:  # PARAMETER_STRING
            val = value.string_value
        elif value.type == 5:  # PARAMETER_BYTE_ARRAY
            val = value.byte_array_value
        elif value.type == 6:  # PARAMETER_BOOL_ARRAY
            val = value.bool_array_value
        elif value.type == 7:  # PARAMETER_INTEGER_ARRAY
            val = value.integer_array_value
        elif value.type == 8:  # PARAMETER_DOUBLE_ARRAY
            val = value.double_array_value
        elif value.type == 9:  # PARAMETER_STRING_ARRAY
            val = value.string_array_value
        else:
            val = "Unknown type"
        print(f"{name}: {val}")
    
    param_query.destroy_node()
    rclpy.shutdown()

if __name__ == '__main__':
    main()

Example output

qos_overrides./parameter_events.publisher.depth: 1000
qos_overrides./parameter_events.publisher.durability: volatile
qos_overrides./parameter_events.publisher.history: keep_last
qos_overrides./parameter_events.publisher.reliability: reliable
start_type_description_service: True
tf_buffer_cache_time_ms: 10000
use_sim_time: False