iso 1.0.0

An isolates runner that handles bidirectionnal communication. Run some code in an isolate and communicate with it

Iso

An isolates runner that handles bidirectionnal communication. Run some code in an isolate and communicate with it.

Example

import 'package:iso/iso.dart';

void run(IsoRunner iso) async {
  int counter = 0;
  // init the data in channel
  iso.receive();
  // listen to the data coming in
  iso.dataIn.listen((dynamic data) {
    counter = counter + int.parse("$data");
    // send into the main thread
    iso.send(counter);
  });
}

void main() async {
  final iso = Iso(run, onDataOut: (dynamic data) => print("Counter: $data"));
  iso.run();
  await iso.onCanReceive;
  // now we can send messages to the isolate
  while (true) {
    await Future<dynamic>.delayed(Duration(seconds: 1));
    iso.send(1);
  }
}

Usage

Initialize

Define a function to be run in an isolate:

void run(IsoRunner iso) {
   // do something here
}

Important: this must be a top level function or a static method. The function can be async if needed

Initialize a runner:

final iso = Iso(run);

Launch the function in the isolate:

iso.run();
// to terminate it:
iso.dispose();

The function can be run with parameters:

final params = <dynamic>["arg1", "arg2", 3];
iso.run(params);

To grab the parameters in the isolate:

void run(IsoRunner iso) {
   if (iso.hasArgs) {
     final List<dynamic> args = iso.args;
   }
}

Communication channels

Data coming from the isolate

Handle data coming from the isolate using a handler function:

void onDataOut(dynamic data) => print("Data coming from isolate: $data");

final iso = Iso(run, onDataOut: onDataOut);

Another option to handle this data is to listen to a channel:

iso.dataOut.listen((dynamic payload) {
  if (payload == <String, dynamic>{"status": "finished"}) {
    print("Isolate declares it has finished");
    iso.kill();
  }
});

Data coming into the isolate

By default this data channel is not activated: you need to do it in the run function if needed:

void run(IsoRunner iso) {
  iso.receive();
  iso.dataIn.listen((dynamic data) {
    // do something with the data
  });
}

or:

void run(IsoRunner iso) {
  iso.receive()
    ..listen((dynamic data) =>
      print("Data received in isolate -> $data / ${data.runtimeType}"));
}

Send data to the isolate

This has to be initialized in the isolate before sending as explained above.

iso.run();
// wait for the isolate to be ready to receive data
await iso.onCanReceive;
// send data
iso.send("Some data");

Send data from the isolate to the main thread

void run(IsoRunner iso) {
   // ...
   iso.send("Some data");
}

Examples

Check the example folder to see examples for Dart and Flutter