Micro-ros Ping utility issue

[apurva-peppermint]

Issue template

• Hardware description: esp32s3 devkit
• RTOS: freertos
• Installation type: standard
• Version or commit hash: humble

Steps to reproduce the issue

try the rmw_uros_ping_agent() utility to see whether the Agent is up or not it does not require creating a micro-ros context first...

Expected behavior

When I turn the Agent on it should output as RMW_RET_OK else it should throw an error value

Actual behavior

There is a variable called agent_state_flag in the code which gives 0 when agent is off and 1 when agent is on...

Here I have not started the agent yet

Here I have started the agent

Still it the rmw_uros_ping_agent() is not giving me a RMW_RET_OK even when the agent is alive

Additional information

The code snippet which I am using...

[pablogs9]

Hello @apurva-peppermint please provide code for replicating this.

[apurva-peppermint]

Hey @pablogs9 I'm using this code for the agent liveliness testing...

#include <string.h>
#include <stdio.h>
#include <unistd.h>

#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "esp_log.h"
#include "esp_system.h"
#include "driver/gpio.h"
#include "freertos/queue.h"
#include "driver/uart.h"

#include <uros_network_interfaces.h>
#include <rcl/rcl.h>
#include <rcl/error_handling.h>
// #include <std_msgs/msg/int32.h>
#include <std_msgs/msg/float32.h>
#include <rclc/rclc.h>
#include <rclc/executor.h>

#ifdef CONFIG_MICRO_ROS_ESP_XRCE_DDS_MIDDLEWARE
#include <rmw_microros/rmw_microros.h>
#endif

#define RCCHECK(fn) { rcl_ret_t temp_rc = fn; if((temp_rc != RCL_RET_OK)){printf("Failed status on line %d: %d. Aborting.\n",__LINE__,(int)temp_rc);vTaskDelete(NULL);}}
#define RCSOFTCHECK(fn) { rcl_ret_t temp_rc = fn; if((temp_rc != RCL_RET_OK)){printf("Failed status on line %d: %d. Continuing.\n",__LINE__,(int)temp_rc);}}

int agent_state_flag = 0;

void agent_notifier(void *arg)
{
    while(1)
    {
        if(rmw_uros_ping_agent(100, 1) == RMW_RET_OK)
        {
            agent_state_flag = 1;
            printf("agent_state_flag = %d\n", agent_state_flag);
        }
        else
        {
            agent_state_flag = 0;
            printf("agent_state_flag = %d\n", agent_state_flag);
        }
    }       
}

void app_main(void)
{
#if defined(CONFIG_MICRO_ROS_ESP_NETIF_WLAN) || defined(CONFIG_MICRO_ROS_ESP_NETIF_ENET)
    ESP_ERROR_CHECK(uros_network_interface_initialize());
#endif

     xTaskCreate(agent_notifier,
                "agent_notifier_task",
                1024 * 4,
                NULL,
                CONFIG_MICRO_ROS_APP_TASK_PRIO ,
                NULL);
}

[pablogs9]

Please paste here the output of the micro-ROS Agent using the flag -v6 to increase verbosity.

[apurva-peppermint]

[pablogs9]

If you use a normal micro-ROS example (publisher for example), does it works?

[apurva-peppermint]

I have not tried that yet. So I want the client to start the context only when it detects that an agent has started or has become alive again. This ping function works when I first start the Agent and then my client with all the initializations and running the executor. but if I try pinging the agent before creating anything as I have written in the code it does not work

[pablogs9]

Probable dealing with an agent pinging on a non-initialized session can be weird due to the fact that it will try to open/close sockets...In your example, does the board send any UDP packet to multicast or to the agent IP address?

[apurva-peppermint]

I will check and let you know here

[apurva-peppermint]

hey @pablogs9 I just checked it and the board does not send any kind of UDP packet to the agents IP address. It only sends a packet when a micro ros session is on.