the-algorithm/product-mixer/component-library/src/main/scala/com/twitter/product_mixer/component_library/premarshaller/urt/builder/PinEntryInstructionBuilder.scala
twitter-team ef4c5eb65e Twitter Recommendation Algorithm
Please note we have force-pushed a new initial commit in order to remove some publicly-available Twitter user information. Note that this process may be required in the future.
2023-03-31 17:36:31 -05:00

24 lines
1.0 KiB
Scala

package com.twitter.product_mixer.component_library.premarshaller.urt.builder
import com.twitter.product_mixer.core.model.marshalling.response.urt.PinEntryTimelineInstruction
import com.twitter.product_mixer.core.model.marshalling.response.urt.TimelineEntry
import com.twitter.product_mixer.core.pipeline.PipelineQuery
import com.twitter.product_mixer.core.model.marshalling.response.urt.metadata.PinnableEntry
case class PinEntryInstructionBuilder()
extends UrtInstructionBuilder[PipelineQuery, PinEntryTimelineInstruction] {
override def build(
query: PipelineQuery,
entries: Seq[TimelineEntry]
): Seq[PinEntryTimelineInstruction] = {
// Only one entry can be pinned and the desirable behavior is to pick the entry with the highest
// sort index in the event that multiple pinned items exist. Since the entries are already
// sorted we can accomplish this by picking the first one.
entries.collectFirst {
case entry: PinnableEntry if entry.isPinned.getOrElse(false) =>
PinEntryTimelineInstruction(entry)
}.toSeq
}
}