dartrosa_external_data

ODK Collect's external data ("dynamic preload") for DartRosa: pulldata() and search() appearances over CSV form media. A port of Collect's dynamicpreload package and the entities module's PullDataFunctionHandler.

• Add an ExternalDataPlugin to DartRosaConfig.plugins: CSV media are imported when the form loads (into an ExternalDataRepository; in memory by default, or your own persistent one to import only changed files), pulldata() is registered, and saved instances are typed as Collect types them.
• Read the choices of selects with a search() appearance with loadSelectChoices; dartrosa_flutter does this for you.
• PullDataInstanceAdapter lets other sources (such as dartrosa_entities' local entity lists) answer pulldata() first.

Install

dart pub add dartrosa_external_data

Example

import 'dart:convert';

import 'package:dartrosa/dartrosa.dart';
import 'package:dartrosa_external_data/dartrosa_external_data.dart';

Future<void> main() async {
  final config = DartRosaConfig(
    // Form media, read as jr://file/<name>.
    resolver: MapResourceResolver({
      'jr://file/fruits.csv': utf8.encode('name,price\nmango,1.5\n'),
    }),
    plugins: [
      ExternalDataPlugin(listMedia: (_) => ['fruits.csv']),
    ],
  );
  // The form calculates pulldata('fruits', 'price', 'name', /data/fruit).
  final definition = await FormDefinition.parse(xform, config: config);
  final session = definition.createSession();
  final [fruit, price] = session.root.children.cast<QuestionNode>();
  session.answer(fruit.index, const StringValue('mango'));
  print(price.value?.displayText); // 1.5
}

See example/example.dart for the complete program.

Documentation

• API reference
• Documentation index
• Use CSV data and entities
• Plugins and extension points
• Getting started
• Compatibility matrix
• Migrating from JavaRosa

License

Apache License 2.0 (see LICENSE). Ports ODK Collect code (Apache-2.0); see the licensing notes.