mDNS discovery with IDE cannot detect the board name

[luc-github]

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• [ x] I have read the documentation at readthedocs and the issue is not addressed there.
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Platform

• Hardware: ESP-12
• Core Version: [latest git ]
• Development Env: [Arduino IDE]
• Operating System: [Windows]

Settings in IDE

• Module: [Generic ESP8266 ]
• Flash Mode: [dio]
• Flash Size: [4MB]
• lwip Variant: [v2 Lower Memory]
• Reset Method: [nodemcu]
• Flash Frequency: [40Mhz]
• CPU Frequency: [160MHz]
• Upload Using: [OTA]
• Upload Speed: [115200|]

Problem Description

OTA description is incomplete - variant is missing in description in Arduino OTA menu unlike for ESP32

it is due to property board which should contain the variant name, but ESP8266 put another string

string is put here (thanks @tobozo to find out)
https://github.com/esp8266/Arduino/blob/master/libraries/ESP8266mDNS/src/LEAmDNS.cpp#L1278
and also https://github.com/esp8266/Arduino/blob/master/libraries/ESP8266mDNS/src/LEAmDNS2Host.cpp#L792
So arduino IDE cannot match the variant with one present in board.txt

if I hardcode "generic" for the variant on board property - the result is correct

[mcspr]

Slight correction: "board" from mDNS (for some reason) should be equal to the ID of the board, not the whatever value we set to either board= or variant=
This is true for both the old IDE and the new one; see arduino-cli board list with mDNS discovery enabled
https://github.com/arduino/Arduino/blob/57a931c9c4c084057417837239ad8136f8a7b1aa/arduino-core/src/cc/arduino/packages/discoverers/NetworkDiscovery.java#L113-L119
https://github.com/arduino/arduino-cli/blob/63b53c0fa6830ce77cfb5508f06b2b4e601c90b5/cli/board/list.go#L134
(where identification prop map of this specific board is {board: d1_mini})

For example, if we select LOLIN(WEMOS) D1 R2 & mini, mDNS should return d1_mini. No relation to the similarly named build.variant=, just the root of the property.

Arduino/boards.txt

Line 3848 in a2982f9

d1_mini.name=LOLIN(WEMOS) D1 R2 & mini

esp32 seems to use a different scheme btw, by introducing ARDUINO_VARIANT flag and using it's value

[mcspr]

(where identification prop map of this specific board is {board: d1_mini})

...which we could find out normally, without going too far into the arduino-cli code

$ arduino-cli.exe board details -b $board_fqbn

for example, huzzah

$ arduino-cli.exe board details -b esp8266com:esp8266:huzzah
Board name:                Adafruit Feather HUZZAH ESP8266
FQBN:                      esp8266com:esp8266:huzzah
Board version:             3.1.0-dev

Identification properties: board=huzzah
...

edit:
Only issue now... how does one inject board ID into the build process? Inject another property ...=$id?
edit2:
Answering myself, we just inject this ${_id} somewhere as string

$ arduino-cli compile --show-properties -b esp8266com:esp8266:d1_mini
_id=d1_mini
...