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Description:

data channel

Introduction #
Data Channel for Dart and Flutter.
data_channel (DC) is a simple dart utility for handling exceptions and data routing.
It is not a very ideal solution to handle exceptions using try and catch at every function, use data_channel instead. data_channel will take care of the routing of errors and data.
Installation #
Go to https://pub.dev/packages/data_channel#-installing-tab- for the latest version of data_channel
Example #
Return data from getStarwarsCharacters method
import 'package:data_channel/data_channel.dart';

Future<DC<Exception, StarwarsResponse>> getStarwarsCharacters() async {
try {
final _response = await http.get('https://starwars-api.com/characters');

if (_response.body != null) {
_starWarsData = StarwarsResponse.fromJson(
json.decode(_response.body) as Map<String, dynamic>);
} else {
_exception = Exception('No data available');
}

if (_exception != null) {
return DC.error(
_exception,
);
}

return DC.data(
_starWarsData,
);
} on Exception {
return DC.error(
Exception('Some error occured'),
);
}
}
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Check for errors
void getStarwarsCharacters() async {
final _starWarsData = await getStarwarsCharacters();

if (_starWarsData.hasError) {
// do something
} else if (_starWarsData.hasData) {
// do something
}
}
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DC forward
forward will help to avoid redundant error checks. We can easily forward a different data model to the callee instead of the original incoming data model. DC.forward will forward the error, if present, else data will be returned.
Future<DC<Exception, UserModel>> checkSomethingAndReturn() {
final _starWarsData = await getStarwarsCharacters();

return DC.forward(
loginData,
UserModel(id: _starWarsData.id),
);
}
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DC pick
Cherry pick values using DC.pick

onError will return error, if present
onNoError will return data if error is not present
onData will return data if data is available
onNoData will return if data is not available

final appData = await getSomeLoginData();
appData.pick(
onError: (error) {
if (error is CacheException) {
alerts.setException(context, error);
}
},
onData: (data) {
value1 = data;
},
onNoData: () {
value1 = getDefaultValue();
},
);

// or

appData.pick(
onError: (error) {
if (error is CacheException) {
alerts.setException(context, error);
}
},
onNoError: (data) {
if (data != null) {
value1 = data;

return;
}

value1 = getDefaultValue();
},
);
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Buy me a coffee #
Help me keep the keep building FREE and Open-Source software for all.

Donate Via PayPal: paypal.me/ganeshrvel
Buy Me A Coffee (UPI, PayPal, Credit/Debit Cards, Internet Banking): buymeacoffee.com/ganeshrvel

Contacts #
Please feel free to contact me at ganeshrvel@outlook.com
About #

Author: Ganesh Rathinavel
License: MIT
Package URL: https://pub.dev/packages/data_channel
Repo URL: https://github.com/ganeshrvel/pub-data-channel
Contacts: ganeshrvel@outlook.com

License #
data_channel | Data Channel for Dart and Flutter. MIT License.
Copyright © 2018-Present Ganesh Rathinavel