yahoo_finance_data_reader

Description:

yahoo finance data reader

This project started as a migration of the pandas datareader functionality to read yahoo finance stock prices.
In December of 2022 yahoo started to encrypt the data in the HTML, so I needed to investigate a way of evolving the package.
And then found a yfinance package that used query2 of yahoo finance API, and started to use it
https://github.com/pydata/pandas-datareader/blob/main/pandas_datareader/yahoo/daily.py
This lib have a strong advantage on backtesting strategies as it can give all the dataframe in yahoo finance, this means that can get daily data on futures like NQ=F and ES=F since 2000 and it goes as far as getting data from 1927 on the SP500 yahoo finance symbol ^GSPC

Features #
Get daily data from yahoo finance for the entire dataframe available
Getting started #
Add the dependency to your pubspec.yaml:
yahoo_finance_data_reader: ^1.0.7
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Usage #
YahooFinanceResponse response = await YahooFinanceDailyReader().getDailyDTOs('GOOG');
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Additional information #
To include in your app as a widget you can start with this future builder and debug your way until your desired result
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: 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 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 = 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)}'),
],
),
],
),
),
);
}
}
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Like us on pub.dev #
Package url:
https://pub.dev/packages/yahoo_finance_data_reader
Instruction to publish the package to pub.dev #
dart pub publish