activity_files 0.7.2

A pure Dart toolkit for parsing, editing, validating, and converting workout activity files in GPX, TCX, FIT, GeoJSON, and CSV formats.

activity_files

A pure Dart toolkit for parsing, editing, validating, and converting workout activity files in GPX, TCX, FIT, GeoJSON, and CSV formats.

Highlights

• Format-agnostic RawActivity model covering GPS points, laps, sensor channels, and device metadata.
• ActivityFiles facade and CLI: load, normalize, validate, and convert between all five formats in a few calls.
• Stream-aware builders (builderFromStreams, convertAndExport) accept raw timestamp/value tuples, so servers can skip manual model assembly.
• Parsers never throw on malformed files; every issue is reported as a diagnostic with a stable code, a suggestedFix, and a priority.
• FIT session and lap statistics on ActivitySummary and Lap, mapped per the official FIT profile and verified against real device files, including swim metrics (pool length, stroke, lengths) and strength sets (WorkoutSet).
• Point-level editing on RawEditor: insertPoint, deletePointAt, updatePoint, deleteRange, insertPause, removePause.
• Multi-sport workflows: ActivityFiles.merge(preserveSportPerLap: true) combines swim/bike/run files into one triathlon; splitBySport() breaks a multi-sport file back into single-sport activities.
• Batch import (ActivityFiles.loadBatch) with per-file error capture and progress reporting.
• Multi-track GPX round-trips: extra <trk> elements survive GPX export; single-track targets (TCX/FIT/CSV/GeoJSON) merge them so no points are lost.
• Encoder options for GPX 1.0/1.1 and TCX v1/v2 output, channel tolerances, and coordinate precision.

Call for real-world files

As I only have one fitness tracking device, real-world GPX, TCX, FIT, GeoJSON, and CSV files are highly appreciated. Contributed files are used for local testing only; they are never published or committed to the repository. Please send them to: [e-mail]

Quick links

• Usage guide – Flutter, CLI, streaming, and error-handling walkthroughs.
• Example app – runnable end-to-end demo: load, edit, validate, export.
• CHANGELOG – migration notes and release history.

Getting started

Add the package to pubspec.yaml:

dependencies:
  activity_files: ^0.7.2

Then install dependencies:

dart pub get

Then jump straight into the facade:

import 'package:activity_files/activity_files.dart';

Future<void> convertGpxToFit(Uint8List bytes) async {
  // 1) Load + auto-detect format.
  final load = await ActivityFiles.load(
    bytes,
    useIsolate: true,
  );
  if (load.hasErrors) {
    throw StateError('Load failed:\n${load.diagnosticsSummary()}');
  }

  // 2) Normalize (sort/dedup + trim invalid points) before exporting.
  final normalized = ActivityFiles.normalizeActivity(load.activity);

  // 3) Export with validation so warnings/errors surface alongside the payload.
  final export = ActivityFiles.export(
    activity: normalized,
    to: ActivityFileFormat.fit,
    runValidation: true,
  );
  if (export.hasErrors) {
    throw StateError('Export failed:\n${export.diagnosticsSummary()}');
  }

  // 4) Use the payload. FIT is binary; GPX/TCX use `asString()`.
  final fitBytes = export.asBytes();
  // upload(fitBytes);
}

For the detailed Flutter, streaming, CLI, and isolate walkthroughs, see the usage guide; for a complete runnable program (load → normalize → validate → export), see example/main.dart.

Working with large or malformed files

• Parsing/export never throw on malformed input; check hasErrors and diagnosticsSummary() on the result (see error handling).
• Inline payloads/streams are capped at 64MB (ActivityFiles.defaultMaxPayloadBytes); use useIsolate/exportInIsolate and the streaming APIs for bigger files (see async export & streaming).
• GPX multi-track inputs are flattened when exported to single-track formats (no points lost); TCX multi-activity inputs are merged on parse instead, with per-lap sport preserved. See format handling for details.

Contributing

Issues and pull requests are welcome, especially for additional format fixtures. The package is released under the BSD 3-Clause license.