Network discovery and mDNS management. More...

Macros
#define	EIF_MDNS_TXT_RECORDS_MAX_COUNT 32
	Maximum number of mDNS txt-records.

Functions
esp_err_t	eif_set_mdns (const char const hostname, const char const instance_name)
	Configure the mDNS hostname and instance name. More...

esp_err_t	eif_set_mdns_records (const mdns_txt_item_t txt_records[EIF_MDNS_TXT_RECORDS_MAX_COUNT], size_t txt_records_count)
	Set custom TXT records for mDNS service discovery. More...

Detailed Description

Note: This module is available when Kconfig option CONFIG_EIF_ENABLE_MDNS is enabled and you include this line at the beginning of the file.:
#include <esp_iot_framework_core_mdns.h>

This module allows you to configure mDNS. mDNS enables the device to be discovered via a human-readable name (e.g., my-device.local) instead of an IP address.

The framework automatically appends a unique identifier based on the MAC address to prevent network collisions (e.g., common hostname set: esp32.local, the framework turns this into esp32-1a2b3c.local on a device with MAC XX:XX:XX:1A:2B:3C).

Note: In case the mDNS hostname is not set, device will be used as the common hostname. To disable mDNS, turn off Kconfig option CONFIG_EIF_ENABLE_MDNS.

If you frequently need to enable and disable mDNS during development, you can use the following construct:

#include <mdns.h>
#include <esp_err.h>
#include <esp_iot_framework_core.h>
#ifdef CONFIG_EIF_ENABLE_MDNS
    #include <esp_iot_framework_core_mdns.h>
#endif
 
// Not necessary, but nice :)
#ifdef CONFIG_EIF_ENABLE_MDNS
    static const mdns_txt_item_t my_txt_records[] = {
        {"friendly_name", "Kitchen Main Light"},
        {"room",          "Kitchen"},
        {"hardware",      "ESP32-S3-DevKit"},
        {"v",             "1.0.4"}
    };
#endif
 
void app_main(void) {
    ESP_ERROR_CHECK(eif_core_initialize());
    ESP_ERROR_CHECK(eif_nvs_initialize());
 
    #ifdef CONFIG_EIF_ENABLE_MDNS
        ESP_ERROR_CHECK(eif_set_mdns("my-esp", "Smart Controller"));
        ESP_ERROR_CHECK(eif_set_mdns_records(my_txt_records, 4));
    #endif
 
    // Further code...
}

Function Documentation

◆ eif_set_mdns()

esp_err_t eif_set_mdns	(	const char *const	hostname,
		const char *const	instance_name
	)

Sets the base identity of the device on the local network.

Note: This function must be called after eif_core_initialize() but before eif_wifi_initialize().

Parameters

hostname	Base name prefix (e.g., "my-sensor"). Max length: `32`.
instance_name	Friendly name for discovery tools (e.g., "Main Hall Sensor"). If `NULL` or empty, the formatted `mdns_hostname`(with MAC) will be used as the instance name by default.

Returns

ESP_OK: Configuration stored.
ESP_ERR_INVALID_ARG: The pointer hostname or instance_name is NULL.
ESP_ERR_INVALID_SIZE: The length of the hostname or instance_name is outside the acceptable range.

Example of use:

#include <esp_err.h>
#include <esp_iot_framework_core.h>
#include <esp_iot_framework_core_mdns.h>
 
void app_main(void) {
    ESP_ERROR_CHECK(eif_core_initialize());
    ESP_ERROR_CHECK(eif_nvs_initialize());
    ESP_ERROR_CHECK(eif_set_mdns("my-esp", "Smart Controller"));
 
    // Further code...
}  

◆ eif_set_mdns_records()

esp_err_t eif_set_mdns_records	(	const mdns_txt_item_t	txt_records[EIF_MDNS_TXT_RECORDS_MAX_COUNT],
		size_t	txt_records_count
	)

TXT records allow you to broadcast additional metadata about the device (e.g., firmware version, model, or status). The framework creates an internal copy of the structure, so the original data's lifecycle no longer matters after the call.

Note: This function must be called after eif_core_initialize() but before eif_wifi_initialize().

Warning: The handler array length must be equal to txt_records_count. If the count exceeds the actual array length, a Buffer Overread will occur. If the count is less than the actual length, error ESP_ERR_INVALID_ARG will return.
If the array is accessible by value at the function call site, you can use the following code to automatically calculate the length:
sizeof(array) / sizeof(array[0])