PublisherOps

Attributes

chunkSize

setup the number of elements asked each time from the Publisher. A high number may be useful if the publisher is triggering from IO, like requesting elements from a database. A high number will also lead to more elements in memory. The stream will not emit new element until, either the Chunk is filled or the publisher finishes.

Example:

scala> import cats.effect.IO
scala> import fs2.Stream
scala> import fs2.interop.flow.syntax._
scala> import java.util.concurrent.Flow.Publisher
scala>
scala> def getThirdPartyPublisher(): Publisher[Int] = ???
scala>
scala> // Interop with the third party library.
scala> Stream.eval(IO.delay(getThirdPartyPublisher())).flatMap { publisher =>
    |   publisher.toStream[IO](chunkSize = 16)
    | }
res0: Stream[IO, Int] = Stream(..)

Source:

syntax.scala