yahoo_finance_data_reader 1.0.10

Data reader for yahoo finance to get daily stocks prices. It can be used to develop backtests and it can get all the historic daily data on yahoo finance

example/lib/main.dart

import 'package:flutter/material.dart';
import 'package:intl/intl.dart';
import 'package:yahoo_finance_data_reader/yahoo_finance_data_reader.dart';

void main() {
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return const MaterialApp(
      title: 'Flutter Demo',
      debugShowCheckedModeBanner: false,
      home: BottomSelectionWidget(),
    );
  }
}

class BottomSelectionWidget extends StatefulWidget {
  const BottomSelectionWidget({super.key});

  @override
  State<BottomSelectionWidget> createState() => _BottomSelectionWidgetState();
}

class _BottomSelectionWidgetState extends State<BottomSelectionWidget> {
  int _selectedIndex = 0;
  final PageController _pageController = PageController();

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Yahoo Finance Example'),
      ),
      body: Container(
        padding: const EdgeInsets.all(20.0),
        child: PageView(
          physics: const NeverScrollableScrollPhysics(),
          controller: _pageController,
          onPageChanged: _onItemSelected,
          children: const [
            YahooFinanceServiceWidget(),
            DTOSearch(),
            RawSearch(),
          ],
        ),
      ),
      bottomNavigationBar: BottomNavigationBar(
        onTap: _onItemSelected,
        currentIndex: _selectedIndex,
        items: const [
          BottomNavigationBarItem(
            icon: Icon(Icons.storage),
            label: 'Service',
          ),
          BottomNavigationBarItem(
            icon: Icon(Icons.format_list_numbered),
            label: 'DTO',
          ),
          BottomNavigationBarItem(
            icon: Icon(Icons.raw_on),
            label: 'Raw',
          ),
        ],
      ),
    );
  }

  void _onItemSelected(int index) {
    setState(() {
      _pageController.animateToPage(index,
          duration: const Duration(milliseconds: 200), curve: Curves.easeOut);
      _selectedIndex = index;
    });
    debugPrint(index.toString());
  }
}

class RawSearch extends StatefulWidget {
  const RawSearch({
    super.key,
  });

  @override
  State<RawSearch> createState() => _RawSearchState();
}

class _RawSearchState extends State<RawSearch> {
  @override
  Widget build(BuildContext context) {
    String ticker = 'GOOG';
    YahooFinanceDailyReader yahooFinanceDataReader =
        const YahooFinanceDailyReader();

    Future<Map<String, dynamic>> future =
        yahooFinanceDataReader.getDailyData(ticker);

    return FutureBuilder(
      future: future,
      builder:
          (BuildContext context, AsyncSnapshot<Map<String, dynamic>> snapshot) {
        if (snapshot.connectionState == ConnectionState.done) {
          if (snapshot.data == null) {
            return const Text('No data');
          }

          Map<String, dynamic> historicalData = snapshot.data!;
          return SingleChildScrollView(
            child: Text(historicalData.toString()),
          );
        } else if (snapshot.hasError) {
          return Text('Error ${snapshot.error}');
        }

        return const Center(
          child: SizedBox(
            height: 50,
            width: 50,
            child: CircularProgressIndicator(),
          ),
        );
      },
    );
  }

  String generateDescription(DateTime date, Map<String, dynamic> day) {
    return '''$date
open: ${day['open']}
close: ${day['close']}
high: ${day['high']}
low: ${day['low']}
adjclose: ${day['adjclose']}
''';
  }
}

class DTOSearch extends StatefulWidget {
  const DTOSearch({super.key});

  @override
  State<DTOSearch> createState() => _DTOSearchState();
}

class _DTOSearchState extends State<DTOSearch> {
  final TextEditingController controller = TextEditingController(
    text: 'GOOG',
  );
  late Future<YahooFinanceResponse> future;

  @override
  void initState() {
    super.initState();
    load();
  }

  @override
  Widget build(BuildContext context) {
    return Column(
      children: [
        const Text('Ticker from yahoo finance'),
        TextField(
          controller: controller,
        ),
        MaterialButton(
          onPressed: load,
          child: const Text('Load'),
          color: Theme.of(context).primaryColor,
        ),
        Expanded(
          child: FutureBuilder(
            future: future,
            builder: (BuildContext context,
                AsyncSnapshot<YahooFinanceResponse> snapshot) {
              if (snapshot.connectionState == ConnectionState.done) {
                if (snapshot.data == null) {
                  return const Text('No data');
                }

                YahooFinanceResponse response = snapshot.data!;
                return ListView.builder(
                    itemCount: response.candlesData.length,
                    itemBuilder: (BuildContext context, int index) {
                      YahooFinanceCandleData candle =
                          response.candlesData[index];

                      return _CandleCard(candle);
                    });
              } else {
                return const Center(
                  child: SizedBox(
                    height: 50,
                    width: 50,
                    child: CircularProgressIndicator(),
                  ),
                );
              }
            },
          ),
        ),
      ],
    );
  }

  void load() {
    future = const YahooFinanceDailyReader().getDailyDTOs(controller.text);
    setState(() {});
  }
}

class _CandleCard extends StatelessWidget {
  final YahooFinanceCandleData candle;

  const _CandleCard(this.candle);

  @override
  Widget build(BuildContext context) {
    final String date = candle.date.toIso8601String().split('T').first;

    return Card(
      child: Container(
        margin: const EdgeInsets.all(10),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Row(
              mainAxisAlignment: MainAxisAlignment.spaceEvenly,
              children: [
                Text(date),
              ],
            ),
            const SizedBox(
              height: 10,
            ),
            Row(
              mainAxisAlignment: MainAxisAlignment.spaceEvenly,
              children: [
                Text('open: ${candle.open.toStringAsFixed(2)}'),
                Text('close: ${candle.close.toStringAsFixed(2)}'),
              ],
            ),
            Row(
              mainAxisAlignment: MainAxisAlignment.spaceEvenly,
              children: [
                Text('low: ${candle.low.toStringAsFixed(2)}'),
                Text('high: ${candle.high.toStringAsFixed(2)}'),
              ],
            ),
            Row(
              mainAxisAlignment: MainAxisAlignment.spaceEvenly,
              children: [
                Text('volume: ${candle.volume}'),
                Text('adjclose: ${candle.adjClose.toStringAsFixed(2)}'),
              ],
            ),
          ],
        ),
      ),
    );
  }
}

class YahooFinanceServiceWidget extends StatefulWidget {
  const YahooFinanceServiceWidget({super.key});

  @override
  State<YahooFinanceServiceWidget> createState() =>
      _YahooFinanceServiceWidgetState();
}

class _YahooFinanceServiceWidgetState extends State<YahooFinanceServiceWidget> {
  TextEditingController controller = TextEditingController(
    text: 'GOOG',
  );
  List<YahooFinanceCandleData> pricesList = [];
  List? cachedPrices;
  bool loading = true;
  bool adjust = true;
  DateTime? startDate;

  @override
  void initState() {
    super.initState();
    load();
  }

  void load() async {
    loading = false;
    setState(() {});

    // Get response for the first time
    pricesList = await YahooFinanceService().getTickerData(
      controller.text,
      startDate: startDate,
      adjust: adjust,
    );

    loading = false;
    setState(() {});
  }

  void deleteCache() async {
    loading = true;
    setState(() {});

    await YahooFinanceDAO().removeDailyData(controller.text);
    cachedPrices = await YahooFinanceDAO().getAllDailyData(controller.text);
    loading = false;
    setState(() {});
  }

  void refresh() async {
    cachedPrices = await YahooFinanceDAO().getAllDailyData(controller.text);
    setState(() {});
  }

  @override
  Widget build(BuildContext context) {
    if (loading) {
      return const Center(
        child: CircularProgressIndicator(),
      );
    }

    return ListView.builder(
      itemCount: pricesList.length + 1,
      itemBuilder: (context, i) {
        if (i == 0) {
          final List<String> tickerOptions = [
            'GOOG',
            'ES=F',
            'GC=F',
            'ES=F-0.5, GC=F-0.5',
            'ES=F, GC=F',
            'GOOG, AAPL',
            'AAPL',
            'AMZN',
          ];
          return Card(
            child: Container(
              margin: const EdgeInsets.all(10),
              child: Column(
                children: [
                  SingleChildScrollView(
                    scrollDirection: Axis.horizontal,
                    child: Row(
                      children: tickerOptions
                          .map(
                            (option) => Container(
                              margin: const EdgeInsets.all(5),
                              child: MaterialButton(
                                child: Text(option),
                                onPressed: controller.text == option
                                    ? null
                                    : () {
                                        setState(() {
                                          controller.text = option;
                                        });
                                        load();
                                      },
                                color: Colors.amberAccent,
                              ),
                            ),
                          )
                          .toList(),
                    ),
                  ),
                  SingleChildScrollView(
                    scrollDirection: Axis.horizontal,
                    child: Row(
                      children: [
                        Text(
                          startDate != null
                              ? 'Selected Date:\n ${DateFormat('yyyy-MM-dd').format(startDate!)}'
                              : 'No Date Selected',
                        ),
                        MaterialButton(
                          onPressed: () async {
                            DateTime? picked = await showDatePicker(
                              context: context,
                              initialDate: startDate ?? DateTime.now(),
                              firstDate: DateTime(2000),
                              lastDate: DateTime(2101),
                            );
                            if (picked != null && picked != startDate) {
                              setState(() {
                                startDate = picked;
                              });
                            }
                          },
                          child: const Text(
                            'Select Date',
                            style: TextStyle(color: Colors.blue),
                          ),
                        ),
                      ],
                    ),
                  ),
                  CheckboxListTile(
                    title: const Text('Adjust'),
                    value: adjust,
                    onChanged: (value) =>
                        setState(() => adjust = value ?? false),
                  ),
                  const Text('Ticker from yahoo finance:'),
                  TextField(
                    controller: controller,
                  ),
                  SingleChildScrollView(
                    scrollDirection: Axis.horizontal,
                    child: Row(
                      mainAxisAlignment: MainAxisAlignment.spaceEvenly,
                      children: [
                        MaterialButton(
                          color: Theme.of(context).primaryColor,
                          onPressed: load,
                          child: const Text('Load'),
                        ),
                        const SizedBox(
                          width: 10,
                        ),
                        MaterialButton(
                          color: Theme.of(context).colorScheme.error,
                          onPressed: deleteCache,
                          child: const Text('Delete Cache'),
                        ),
                        const SizedBox(
                          width: 10,
                        ),
                        MaterialButton(
                          color: Theme.of(context).colorScheme.onPrimary,
                          onPressed: refresh,
                          child: const Text('Refresh'),
                        ),
                      ],
                    ),
                  ),
                  Text('Prices in the service ${pricesList.length}'),
                  Text('First date: ${pricesList.first.date}'),
                  Text('First price: ${pricesList.first.adjClose}'),
                  Text('Last date: ${pricesList.last.date}'),
                  Text('Last price: ${pricesList.last.adjClose}'),
                  Text(
                      'Variation: ${((pricesList.last.adjClose / pricesList.first.adjClose - 1) * 100).toStringAsFixed(2)} %'),
                  Text('Prices in the cache ${cachedPrices?.length}'),
                  pricesList.isEmpty
                      ? const Text('No data')
                      : const SizedBox.shrink()
                ],
              ),
            ),
          );
        } else {
          final YahooFinanceCandleData candleData = pricesList[i - 1];
          return _CandleCard(
            candleData,
          );
        }
      },
    );
  }
}