Experminental PR for adding metadata to protobufs

[jp-bennett]

Can we set devices to DIY vs fully-assembled, and then hide the diy-only options in the apps when connected to a pre-assembled board? Let's find out!

[github-actions]

The latest Buf updates on your PR. Results from workflow pull-request / build (pull_request).

Build	Format	Lint	Breaking	Updated (UTC)
✅ passed	✅ passed	✅ passed	✅ passed	Apr 30, 2026, 8:47 PM

[ianmcorvidae]

Just noting here for good measure, the following patch is needed to make this work in python:

diff --git a/bin/regen-protobufs.sh b/bin/regen-protobufs.sh
index 23def7b..c48b856 100755
--- a/bin/regen-protobufs.sh
+++ b/bin/regen-protobufs.sh
@@ -45,6 +45,8 @@ $SEDCMD 's/^import "meshtastic\//import "meshtastic\/protobuf\//' "${INDIR}/"*.p
 
 $SEDCMD 's/^import "nanopb.proto"/import "meshtastic\/protobuf\/nanopb.proto"/' "${INDIR}/"*.proto
 
+$SEDCMD 's/\(meshtastic.config_field\)/(meshtastic.protobuf.config_field)/' "${INDIR}/"*.proto
+
 # Generate the python files
 ./nanopb-0.4.8/generator-bin/protoc -I=$TMPDIR/in --python_out "${OUTDIR}" "--mypy_out=${PYIDIR}" $INDIR/*.proto

once done, the following procedure gets access to the values:

from meshtastic.protobuf import config_pb2,field_metadata_pb2
field_descriptor = config_pb2.Config.PositionConfig.DESCRIPTOR.fields_by_name['rx_gpio']
options = field_descriptor.GetOptions()
options.Extensions[field_metadata_pb2.config_field].diy_only # returns True

[jamesarich]

Updated to use scalars:

Proto Simplification: field_metadata.proto → scalar extensions

TL;DR: Flattening (meshtastic.config_field).diy_only to a simple (meshtastic.diy_only) bool extension eliminates ~200 lines of custom Wire build code on Android and simplifies access for every downstream client.

What changes in the proto

- message ConfigFieldMetadata {
-   required bool diy_only = 1 [default = false];
- }
- extend google.protobuf.FieldOptions {
-   optional ConfigFieldMetadata config_field = 51001;
- }
+ extend google.protobuf.FieldOptions {
+   optional bool diy_only = 51001 [default = false];
+ }

Usage: [(meshtastic.config_field).diy_only = true] → [(meshtastic.diy_only) = true]

Impact per client

Client	Tool	Impact
Android	Wire 6.2	✅ Wire natively emits @DiyOnlyOption(true) on generated fields
Apple	protoc-gen-swift	✅ generates var diyOnly: Bool extension on FieldOptions directly
Python	protoc	✅ Extensions[diy_only] returns bool directly instead of unwrapping a message
Firmware	nanopb	✅ No impact — nanopb ignores custom options

Extensibility

Future metadata (e.g. admin_only, min_value) → just add more scalar extensions in the 51000–51999 range. No shared wrapper message to evolve.

[jamesarich]

Superseded by #952 — generalizes this experiment into a structured FieldMetadata option (one FieldOptions extension) plus build-time generators that expose it as reflection-free accessors in KMP/Wire, C, Python, TypeScript, Rust, and Swift. Review request is on #952; thanks for the original spike, @jp-bennett!