Struggling to properly generate Matter code (or IDL)

[JetForMe]

I've successfully modified one of the connectedhomeip examples (temperature-measurement-app) and it works using Matter and Thread on a couple of different ESP32-C6 devices I have. Now I'm trying to add additional endpoints (e.g. PowerSource), and I have to generate the IDL from a modified ZAP file, and then let the build system generate the code from that. But it keeps generating empty code (e.g. FIXED_ENDPOINT_COUNT is defined as 0). I've attached the .zap, and generated .matter files, but I don't understand why the generated code ends up being essentially empty.

The command I used to generate the .matter file:

% cd $(PROJECTPATH)
% ${ESPPATH}/zap-mac-arm64/zap-cli generate --zcl ${ESPPATH}/esp-matter/connectedhomeip/connectedhomeip/src/app/zap-templates/zcl/zcl.json --generationTemplate ${ESPPATH}/esp-matter/connectedhomeip/connectedhomeip/src/app/zap-templates/matter-idl-server.json -i main/datamodel.zap -o zap-generated

The generated .matter file seems correct to me, but I can't be sure at all.

(I had to add filename extensions so Github would accept the files.)

datamodel.zap.json

Clusters.matter.txt

Any suggestions on what I might be doing wrong would be greatly appreciated!

[bzbarsky-apple]

That .matter file looks fine, yes. The codegen that ends up generating FIXED_ENDPOINT_COUNT uses the .zap file as input, not the .matter file, for what it's worth. I don't know exactly which build system you are using and which commands it's running, so hard to say anything intelligent about that part; see the docs in docs/zap_and_codegen/code_generation.md in the Matter repo about "codepregen" and maybe look into what that script does to get a sense of what codegen should end up doing at build-time?

[JetForMe]

I'm building with Espressif's idf.py, and at least some of my tooling issues stem from their .cmake files. I eventually got things to kind-of work by creating a manual step that calls zap-cli to generate a .matter file from my .zap file. Then, because of how that command works, I need a manual step to move the file next to the .zap file, and then passing that to the rest of the build lets it finally generate the full set of code. It took many days to get this to work. (I also had to separately install a pre-built version of zap and zap-cli). In case it helps anyone else, this is how I generated the .matter file:

MATTER_CHIP_PATH points to the connectedhomeip subdirectory of the Espressif Matter clone.

ZAP_CLI=~/Projects/Personal/ESP-IDF/zap-mac-arm64/zap-cli
TPL="$MATTER_CHIP_PATH/src/app/zap-templates/matter-idl-server.json"
ZCL="$MATTER_CHIP_PATH/src/app/zap-templates/zcl/zcl.json"
ZAP="$PWD/main/datamodel.zap"
IDL_OUT="$PWD/main/datamodel.matter"

"$ZAP_CLI" generate									\
	--tempState	--noUi --noServer					\
	--zcl "$ZCL"									\
	--generationTemplate "$TPL"						\
	-i "$ZAP"										\
	-o zap-generated

mv zap-generated/Clusters.matter "$IDL_OUT"