--json Outputs JSON objects for --nodes, --request-telemetry/position

[aikomastboom]

In a attempt to make the output of meshtastic a bit more machine parsing friendly (eg by nushell) I propose the addition of '--json' to switch the output to something easily parsable when piped on the commandline.

[CLAassistant]

All committers have signed the CLA.

[holdenweb]

Am I alone in thinking that any output produced in the presence of a --json option should actually be readable as a JSON document? I'm quite happy for other formats to exist, but please let's not mangle existing standards. Transforming JSON is a straightforward task, for which many support libraries exist. Parsing invented almost-JSON formats isn't.

[ianmcorvidae]

It appears that these formats are, in fact, JSON (everything is produced via json.dumps) and could be treated as such.

However, they do look fairly ad-hoc and I think we need a consistent approach, as we're discussing over in #569 -- the discussed plan there so far has largely been to do as little modification of protobufs as we can other than turning them to JSON, and to identify things by the (lowercased) name of the protobuf. This will probably require a bit of internal refactoring for some things (e.g. I don't believe right now we're holding onto a copy of the actual NodeInfo protobufs for nodes, but packing into our own structure instead), but would be much more easily extensible to any other commands and straightforwardly documented in terms of the protobuf definitions.

[aikomastboom]

I totally agree.. it would be preferred to eliminate conversions back and forth into JSON like this. Refactoring the whole codebase to facilitate a clear separation of concern / interface was not my intention. I guess It's best to close this PR and keep the effort to myself while a proper solution is drafted in Discussion: machine-readable output

[Copilot]

Pull Request Overview

This PR enhances meshtastic's command line output by adding a --json flag to produce machine-parsable JSON output for nodes, telemetry, and position requests.

• Updated test cases and mocks to verify the JSON output behavior for node listing.
• Modified methods in mesh_interface.py to accept a jsonResponse flag and print JSON output instead of formatted tables or plain text.
• Enhanced main.py to integrate the --json command line option and adjust its execution flow accordingly.

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
meshtastic/tests/test_main.py	Added and updated test cases to verify JSON output for the --nodes command flag.
meshtastic/mesh_interface.py	Modified showNodes, sendPosition, onResponsePosition, sendTelemetry, and onResponseTelemetry for JSON output; added printJsonPosition and printJsonTelemetry.
meshtastic/main.py	Integrated the --json flag with conditional output behavior for various commands.

Comments suppressed due to low confidence (1)

meshtastic/mesh_interface.py:457

• [nitpick] The JSON output formatting in printJsonPosition and printJsonTelemetry is very similar. Consider creating a shared helper function for JSON formatting to reduce duplication and improve maintainability.

def printJsonPosition(position: mesh_pb2.Position, destinationId: Union[int, str] = BROADCAST_ADDR):

[Copilot]

[nitpick] The showNodes function prints either a table or JSON but always returns the rows list. Consider separating the logic for generating node data from the presentation logic to maintain consistency and better testability.