RxScala – Reactive Extensions for Scala
RxScala is a library for composing asynchronous and event-based programs using observable sequences.
RxScala is open sourced and available under the Apache License, Version 2.0
Questions tagged [rx-scala]
91 questions
0
votes
1 answer
Scala Observable Creation Blocks My Futures
I am wanting to process ea. query fetch (potentially multiple fetches per query) asynchronously. In order to do this, I pass the processing function (which returns a Future) to my query method to call it for ea. fetch. I don't know beforehand the…
juanchito
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1 answer
Scala future-derived observable callbacks not getting called
Using scala 2.11.7, rxscala_2.11 0.25.0, rxjava 1.0.16, my oddFutures callbacks don't get called in AsyncDisjointedChunkMultiprocessing.process():
package jj.async
import scala.concurrent.Future
import scala.concurrent.ExecutionContext
import…
juanchito
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0
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1 answer
`delay` on `interval` will throw `NoSuchElementException`?
Some simple rxscala code:
val s = Observable.interval(Duration("100 millis"))
.zip(Seq(1, 2, 3)).map(_._2).delay(Duration("2 s"))
println(s.toBlocking.toList)
When run it, it throws exception:
Exception in thread "main"…
Freewind
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How to get historical data from a PublishSubject?
How to get all historical data from a PublishSubject?
val ob = PublishSubject[Int]()
ob.subscribe(x => println("a: " + x))
ob.onNext(1)
ob.subscribe(x => println("b: " + x))
ob.onNext(2)
It prints:
a: 1
a: 2
b: 2
You can see there is no b: 1…
Freewind
- 193,756
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0
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0 answers
Combining Observables in RxScala
i was wondering if someone can give me some hints here. I am learning RxScala and i have the following exercise to do:
- Implement an observable object that emits an event every 5 seconds and every 12 seconds
I was wondering if the following code…
user1068378
- 333
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RxScala behave differently in worksheet and after compile
I was playing around with RxScala and Subject in scala worksheet. But something weird happened.
as we can see, subscription c also get numbers and output them. After that, I find subscription c is var not val. So, I change the declare. And get…
Nks Sai
- 23
- 2
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1 answer
How to cause a backpressure exception zipping two Observables?
I'm trying to write a test to see the use of onBackPressureDrop in RxScala.
I'm zipping a fast Obserable with a slow one, with a simple zipping function.
The curious thing is that the same example in RxJava produces the exception but with RxScala…
juanpavergara
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1 answer
RxJava: Blocking on an observable after subscription?
I have a special need for an observable.
Usually, my observables run in a different thread. But, sometimes they need to block another thread in the middle of subscription. Something the way a future behaves.
An example:
val o = Observable.create(/*…
stojanman
- 325
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How to observe on reverse dependency order?
I'd like to observe a tree of objects, in reverse dependency order, but do not know what combinators to use. The specific case is iterating through AWS Resources in order for deletion, for example deleting S3 Objects before deleting their S3…
Julio Faerman
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1 answer
RxScala Observables with replay
I'm trying to understand replay in RxScala. I create an observable like this:
lazy val toyObservable : Observable[Int] = {
val coldObservable : Observable[Int] = intPerSecond
val hotObservable : ConnectableObservable[Int] =…
thund
- 1,842
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0
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1 answer
Scala Reactive Extensions Observable apply Method
From the API docs of Rx Observable in scala:
http://reactivex.io/rxscala/scaladoc/#rx.lang.scala.Observable
There are two apply methods, one that takes a Subscriber and the other that takes an Observer. What is the difference between these two apply…
joesan
- 13,963
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1 answer
RxScala Observer and Subscription
I'm just getting started with RxScala and came across a few examples. I understand that there is an Observable contract in which the Observer trait is defined as follows:
trait Observer[T] {
def onNext(event: T): Unit
def onError(error:…
joesan
- 13,963
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1 answer
RxScala buffer elements
I have application where I need parse strings and I use for it RxScala. My code:
import java.util.concurrent.TimeUnit
import rx.lang.scala.Subject
import rx.lang.scala.schedulers.NewThreadScheduler
import rx.lang.scala.subjects.{SerializedSubject,…
krynio
- 2,442
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2 answers
Implement a recurring job repeating not more than once per second
Suppose we have something like this:
while (true) {
val job = Future { doSomething(); 1 }
val timeout = Future { Thread.sleep(1000); 2 }
val both = for (j <- job; t <- timeout) {
println("Done")
}
Await.result(both)
}
What is the…
Tair
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Reactive Extensions (RxScala) equivalent of fold ifEmpty
I was wondering if there is any equivalent of the Scala fold ifEmpty function that exists for collections and options:
fold[B](ifEmpty: => B)(f: (A) => B)
This function is powerful in that it can transform between different monad types - for…
mixja
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