otel_command_it

OpenTelemetry instrumentation for package:command_it — Thomas Burkhart's Command pattern for Flutter UI actions (renamed from flutter_command at v9.0).

Adds a CLIENT-kind span around every command execution so you can see exactly which button taps / form submits / refresh handlers are slow and which ones throw.

Install

dependencies:
  command_it: ^9.0.0
  otel_command_it: ^0.2.0

If you're still on the legacy package, use otel_flutter_command instead.

Use

Replace .run(...) with .runTraced(...) and .runAsync(...) with .runAsyncTraced(...):

import 'package:command_it/command_it.dart';
import 'package:dartastic_opentelemetry/dartastic_opentelemetry.dart';
import 'package:otel_command_it/otel_command_it.dart';

// Define a command, as usual.
final saveNote = Command.createAsyncNoResult<String>(
  (text) async { await db.save(text); },
);

// In your button handler:
ElevatedButton(
  onPressed: () => saveNote.runAsyncTraced(
    textController.text,
    'saveNote',
  ),
  child: const Text('Save'),
);

For sync commands:

final clearForm = Command.createSyncNoParamNoResult(() {
  textController.clear();
});

ElevatedButton(
  onPressed: () => clearForm.runTraced(null, 'clearForm'),
  child: const Text('Clear'),
);

Span shape

Attribute	Source
command.name	the spanName you pass (defaults to <anonymous>)
command.system	hardcoded command_it
command.result	success or error
error.type	exception class on throw

Span name: command_it <spanName>.

The span captures the full duration of:

• runTraced — from call until run(...) returns (or throws). For async commands this is just the synchronous dispatch; use runAsyncTraced for the awaited duration.
• runAsyncTraced — from call until the underlying Future completes (success or error).

Why call-site instrumentation?

command_it ships two global hooks:

• Command.loggingHandler — fires once at the end of execution. Can't measure duration.
• Command.globalExceptionHandler — fires when an exception escapes a command. Can't measure duration either.

And the per-command results ValueListenable filters out no-op updates with ==. So a createSyncNoParamNoResult command (whose result type is void) emits no result events at all when run, because the new CommandResult compares equal to the initial one.

Call-site instrumentation sidesteps both issues.

Note on async errors

For the runAsyncTraced error path to complete properly, command_it 9.x requires either a local error handler on the command or a global Command.globalExceptionHandler. Without one, runAsync rethrows synchronously and the future never resolves. Set a global handler once at app startup — even a no-op (cmd, err) {} — to keep all async commands well-behaved.

Suppression

await runWithoutCommandItInstrumentationAsync(() async {
  await myCommand.runAsyncTraced(p, 'hot.path');  // skipped
});

See also

• otel_flutter_command — the legacy package wrapper (same API as command_it 8.x).
• otel_get_it — Thomas Burkhart's service locator.
• otel_watch_it — Thomas Burkhart's Flutter binding to get_it.

License

Apache 2.0 — copyright Mindful Software LLC.