Is it possible for a saga to "trace" the effect "chain"?

[David Schontzler]

I'm curious if there's any way for a generator to get information about where it is being used in the effect "chain" to put some trace clues in logs. I'm thinking something like so:

function* sagaOne() {
  const sagaInfo = yield call(getSagaInfo);
  console.log('something important', sagaInfo.effectIds);
  const value = yield call(sagaTwo);
  console.log('the value is', value, sagaInfo.effectIds);
}

function* sagaTwo() {
  const sagaInfo = yield call(getSagaInfo);
  console.log('something else important', sagaInfo.effectIds);
  return 2;
}

I'm imagining the log output might be something like so:

something important [1, 2]
something else important [1, 2, 3]
the value is 2 [1, 2]

And we could then reconstruct a trace of effects that are all strung together. Since there may be any number of effects going on simultaneously, our logs are hard to trace, as async things are not sequential.

[Vlad]

Did you tried simlple-saga-monitor ?

[David Schontzler]

I assumed using the saga monitor would be part of the equation. I'm just not sure if there's a way to match up monitor data and an effect, i.e.: yield call(getSagaMonitorDataForCurrentEffect)

[Vlad]

You will be able to inspect the payload as well.

[Eric Bower]

Saga monitor is where, historically, our effort has gone into tracability.

Having said that, saga-query is a new experimental library that acts as a middleware system for your sagas using express-like middleware.

Using that system, tracability is dramatically improved because you can easily attach loggers to most of your sagas.