Broken on ESP8266 after latest update

[serrj-sv]

src/esphome/components/udpserver/udpserver_component.cpp: In constructor 'esphome::udpserver::WiFiUDPClient::WiFiUDPClient()':
src/esphome/components/udpserver/udpserver_component.cpp:23:59: error: invalid use of incomplete type 'class esphome::udpserver::WiFiUDP'
   23 |         WiFiUDPClient::WiFiUDPClient() : udp_(new WiFiUDP()) {}
      |                                                           ^
In file included from src/esphome/components/udpserver/udpserver_component.cpp:1:
src/esphome/components/udpserver/udpserver_component.h:44:11: note: forward declaration of 'class esphome::udpserver::WiFiUDP'
   44 |     class WiFiUDP;
      |           ^~~~~~~
src/esphome/components/udpserver/udpserver_component.cpp: In destructor 'virtual esphome::udpserver::WiFiUDPClient::~WiFiUDPClient()':
src/esphome/components/udpserver/udpserver_component.cpp:26:13: warning: possible problem detected in invocation of 'operator delete' [-Wdelete-incomplete]
   26 |             delete udp_;
      |             ^~~~~~~~~~~
src/esphome/components/udpserver/udpserver_component.cpp:26:20: warning: invalid use of incomplete type 'class esphome::udpserver::WiFiUDP'
   26 |             delete udp_;
      |                    ^~~~
In file included from src/esphome/components/udpserver/udpserver_component.cpp:1:
src/esphome/components/udpserver/udpserver_component.h:44:11: note: forward declaration of 'class esphome::udpserver::WiFiUDP'
   44 |     class WiFiUDP;
      |           ^~~~~~~
src/esphome/components/udpserver/udpserver_component.cpp:26:13: note: neither the destructor nor the class-specific 'operator delete' will be called, even if they are declared when the class is defined
   26 |             delete udp_;
      |             ^~~~~~~~~~~
src/esphome/components/udpserver/udpserver_component.cpp: In member function 'virtual bool esphome::udpserver::WiFiUDPClient::begin(uint16_t)':
src/esphome/components/udpserver/udpserver_component.cpp:30:24: error: invalid use of incomplete type 'class esphome::udpserver::WiFiUDP'
   30 |             return udp_->begin(port);
      |                        ^~
In file included from src/esphome/components/udpserver/udpserver_component.cpp:1:
src/esphome/components/udpserver/udpserver_component.h:44:11: note: forward declaration of 'class esphome::udpserver::WiFiUDP'
   44 |     class WiFiUDP;
      |           ^~~~~~~
src/esphome/components/udpserver/udpserver_component.cpp: In member function 'virtual bool esphome::udpserver::WiFiUDPClient::receive_packet(esphome::udpserver::UDPPacket&)':
src/esphome/components/udpserver/udpserver_component.cpp:34:34: error: invalid use of incomplete type 'class esphome::udpserver::WiFiUDP'
   34 |             int packetSize = udp_->parsePacket();
      |                                  ^~
In file included from src/esphome/components/udpserver/udpserver_component.cpp:1:
src/esphome/components/udpserver/udpserver_component.h:44:11: note: forward declaration of 'class esphome::udpserver::WiFiUDP'
   44 |     class WiFiUDP;
      |           ^~~~~~~
src/esphome/components/udpserver/udpserver_component.cpp:45:27: error: invalid use of incomplete type 'class esphome::udpserver::WiFiUDP'
   45 |             int len = udp_->read(buffer_, packetSize);
      |                           ^~
In file included from src/esphome/components/udpserver/udpserver_component.cpp:1:
src/esphome/components/udpserver/udpserver_component.h:44:11: note: forward declaration of 'class esphome::udpserver::WiFiUDP'
   44 |     class WiFiUDP;
      |           ^~~~~~~
src/esphome/components/udpserver/udpserver_component.cpp:55:41: error: invalid use of incomplete type 'class esphome::udpserver::WiFiUDP'
   55 |             IPAddress remote_addr = udp_->remoteIP();
      |                                         ^~
In file included from src/esphome/components/udpserver/udpserver_component.cpp:1:
src/esphome/components/udpserver/udpserver_component.h:44:11: note: forward declaration of 'class esphome::udpserver::WiFiUDP'
   44 |     class WiFiUDP;
      |           ^~~~~~~
src/esphome/components/udpserver/udpserver_component.cpp:56:38: error: invalid use of incomplete type 'class esphome::udpserver::WiFiUDP'
   56 |             packet.remote_port = udp_->remotePort();
      |                                      ^~
In file included from src/esphome/components/udpserver/udpserver_component.cpp:1:
src/esphome/components/udpserver/udpserver_component.h:44:11: note: forward declaration of 'class esphome::udpserver::WiFiUDP'
   44 |     class WiFiUDP;
      |           ^~~~~~~
src/esphome/components/udpserver/udpserver_component.cpp: In member function 'virtual bool esphome::udpserver::WiFiUDPClient::send_packet(const string&, const string&, uint16_t)':
src/esphome/components/udpserver/udpserver_component.cpp:68:22: error: invalid use of incomplete type 'class esphome::udpserver::WiFiUDP'
   68 |             if (!udp_->beginPacket(ip.c_str(), port)) {
      |                      ^~
In file included from src/esphome/components/udpserver/udpserver_component.cpp:1:
src/esphome/components/udpserver/udpserver_component.h:44:11: note: forward declaration of 'class esphome::udpserver::WiFiUDP'
   44 |     class WiFiUDP;
      |           ^~~~~~~
src/esphome/components/udpserver/udpserver_component.cpp:71:17: error: invalid use of incomplete type 'class esphome::udpserver::WiFiUDP'
   71 |             udp_->write((const uint8_t*)data.c_str(), data.length());
      |                 ^~
In file included from src/esphome/components/udpserver/udpserver_component.cpp:1:
src/esphome/components/udpserver/udpserver_component.h:44:11: note: forward declaration of 'class esphome::udpserver::WiFiUDP'
   44 |     class WiFiUDP;
      |           ^~~~~~~
src/esphome/components/udpserver/udpserver_component.cpp:72:24: error: invalid use of incomplete type 'class esphome::udpserver::WiFiUDP'
   72 |             return udp_->endPacket();
      |                        ^~
In file included from src/esphome/components/udpserver/udpserver_component.cpp:1:
src/esphome/components/udpserver/udpserver_component.h:44:11: note: forward declaration of 'class esphome::udpserver::WiFiUDP'
   44 |     class WiFiUDP;
      |           ^~~~~~~
*** [.pioenvs/dsmr-p1/src/esphome/components/udpserver/udpserver_component.cpp.o] Error 1

[morris2009]

I have exactly the same error messages when trying to newly implement this.
Also tried on ESPhome 2026-5-0-dev

Maybe removing
class WiFiUDP;

And adding
#include <WiFiUdp.h>
to the top of the .h file and the .cpp file will fix it.

[morris2009]

These changes fixed it for me: #6

[jsimonetti]

thank you! I will have a look at your suggestions. I am not yet on latest esphome so i didn't notice it yet.

[jsimonetti]

@serrj-sv you mention it broke after latest update. Do you mean it is broken on the latest esphome or the latest version of this custom component?

Would you be able to share you device config so I can try to replicate it?

[Tazzios]

I also get the error:

ESPhome 2026.6.4
config that i use is:

substitutions:
  device_name: slimmelezer
  device_description: "DIY P1 module to read your smart meter"

esphome:
  name: ${device_name}
  comment: "${device_description}"

  name_add_mac_suffix: false
  project:
    name: zuidwijk.slimmelezer
    version: "2.0"

esp8266:
  board: d1_mini
  

# Enable logging
logger:
  baud_rate: 0

# Enable Home Assistant API
api:
  encryption:
    key: "key stuff"

ota:
  - platform: esphome
    password: "password"

wifi:
  ssid: !secret wifi_ssid
  password: !secret wifi_password

  # Enable fallback hotspot (captive portal) in case wifi connection fails
  ap:
    ssid: "Slimmelezer Fallback Hotspot"
    password: "password"

captive_portal:

web_server:
  port: 80

uart:
  baud_rate: 115200
  rx_pin: D7
  rx_buffer_size: 1700

dsmr:
  max_telegram_length: 1700

text_sensor:
  - platform: version
    name: "Firmware Version"

  
sensor:
  - platform: dsmr
    energy_delivered_tariff1:
      id: energy_consumed_tariff1
      internal: true #alleen op de ESP bruikbaar
      name: "Energy Consumed Tariff 1"
      accuracy_decimals: 0
    energy_delivered_tariff2:
      id: energy_consumed_tariff2
      internal: true
      name: "Energy Consumed Tariff 2"
      accuracy_decimals: 0
    energy_returned_tariff1:
      id: energy_produced_tariff1
      internal: true
      name: "Energy Produced Tariff 1"
      accuracy_decimals: 0
    energy_returned_tariff2:
      id: energy_produced_tariff2
      internal: true
      name: "Energy Produced Tariff 2"
      accuracy_decimals: 0
    power_delivered:
      id: power_consumed
      internal: true
      name: "Power Consumed"
      accuracy_decimals: 3
    power_returned:
      id: power_produced
      internal: true
      name: "Power Produced"
      accuracy_decimals: 3
    electricity_failures:
      name: "Electricity Failures"
      icon: mdi:alert
    electricity_long_failures:
      name: "Long Electricity Failures"
      icon: mdi:alert
    voltage_l1:
      name: "Voltage Phase 1"
    voltage_l2:
      name: "Voltage Phase 2"
    voltage_l3:
      name: "Voltage Phase 3"
    power_delivered_l1:
      id: power_consumed_l1
      internal: true
      name: "Power Consumed Phase 1"
      accuracy_decimals: 3
    power_delivered_l2:
      id: power_consumed_l2
      internal: true
      name: "Power Consumed Phase 2"
      accuracy_decimals: 3
    power_delivered_l3:
      id: power_consumed_l3
      internal: true
      name: "Power Consumed Phase 3"
      accuracy_decimals: 3
    power_returned_l1:
      id: power_produced_l1
      internal: true
      name: "Power Produced Phase 1"
      accuracy_decimals: 3
    power_returned_l2:
      id: power_produced_l2
      internal: true
      name: "Power Produced Phase 2"
      accuracy_decimals: 3
    power_returned_l3:
      id: power_produced_l3
      internal: true
      name: "Power Produced Phase 3"
      accuracy_decimals: 3
#    gas_delivered:
#      name: "Gas Consumed"

# ESP info
  - platform: uptime
    name: "SlimmeLezer Uptime"
  - platform: wifi_signal
    name: "SlimmeLezer Wi-Fi Signal"
    update_interval: 60s

# Extra verzamel sensors

# Energie 
  - platform: template
    name: "Energy Consumed"
    device_class: energy
    state_class: total_increasing
    unit_of_measurement: "kWh"
    accuracy_decimals: 0
    lambda: |-
      return id(energy_consumed_tariff1).state + id(energy_consumed_tariff2).state;
    update_interval: 10s

  - platform: template
    name: "Energy Produced"
    device_class: energy
    state_class: total_increasing
    unit_of_measurement: "kWh"
    accuracy_decimals: 0
    lambda: |-
      return id(energy_produced_tariff1).state + id(energy_produced_tariff2).state;
    update_interval: 10s

# Vermogen    
  - platform: template
    name: "Power"
    device_class: power
    state_class: measurement
    unit_of_measurement: "kW"
    accuracy_decimals: 3
    lambda: |-
      return id(power_consumed).state - id(power_produced).state;
    update_interval: 1s    

# Vermogen per fase

  - platform: template
    name: "Power fase 1"
    device_class: power
    state_class: measurement
    unit_of_measurement: "kW"
    accuracy_decimals: 3
    lambda: |-
      return id(power_consumed_l1).state - id(power_produced_l1).state;
    update_interval: 1s

  - platform: template
    name: "Power fase 2"
    device_class: power
    state_class: measurement
    unit_of_measurement: "kW"
    accuracy_decimals: 3
    lambda: |-
      return id(power_consumed_l2).state - id(power_produced_l2).state;
    update_interval: 1s

  - platform: template
    name: "Power fase 3"
    device_class: power
    state_class: measurement
    unit_of_measurement: "kW"
    accuracy_decimals: 3
    lambda: |-
      return id(power_consumed_l3).state - id(power_produced_l3).state;
    update_interval: 1s


# Shelly pro 3-EM emulator tbv Marstek

external_components:
  - source: github://jsimonetti/esphome-udpserver
    components: [ udpserver ]


udpserver:
  id: fake_shelly_em
  listen_port: 1010
  allowed_ips:
    - 192.168.178.0/24
  on_string_data:
    - text_filter: "\"method\":\"EM.GetStatus\""
      filter_mode: CONTAINS
      then:
        - lambda: |-
            char buf[512];
            float l1_in = id(power_consumed_l1).state * 1000; // Convert kW to W
            float l1_out = id(power_produced_l1).state * 1000; // Convert kW to W
            float l2_in = id(power_consumed_l2).state * 1000; // Convert kW to W
            float l2_out = id(power_produced_l2).state * 1000; // Convert kW to W
            float l3_in = id(power_consumed_l3).state * 1000; // Convert kW to W
            float l3_out = id(power_produced_l3).state * 1000; // Convert kW to W

            float l1 = l1_in - l1_out; // Net power
            float l2 = l2_in - l2_out; // Net power
            float l3 = l3_in - l3_out; // Net power
            float total = l1 + l2 + l3; // Total power

            int len = snprintf(buf, sizeof(buf),
              "{"
                "\"id\":0,"
                "\"src\":\"shellypro3em-e682e89c1724\","
                "\"dst\":\"unknown\","
                "\"result\":{"
                  "\"a_act_power\":%.1f,"
                  "\"b_act_power\":%.1f,"
                  "\"c_act_power\":%.1f,"
                  "\"total_act_power\":%.3f"
                "}"
              "}",
            l1,
            l2,
            l3,
            total
            ); // Format the JSON response
            
            // Send a response back to the sender
            udp.send_response(buf);

I`m not sure how i can apply #6 by my self.

[jsimonetti]

@Tazzios i also have a zuidwijk p1 meter, only i have an esp32 one. I know I have to older model too, but I don't know where it is unfortunately.
I have merged #6 for now. Perhaps you can test this for us.

[Tazzios]

After cleaning build files it now compiles and installs. Not sure how to test it tough. The Marstek battery will come tomorrow.

the one from jaapp also had a sensor for it to show if it was runnig or not:
https://github.com/jaapp/slimmelezer-shelly-emulator/tree/main

Not sure which one I`m going to use.