Merge branch 'master' into update-zio-quickstart-restful

build.sbt

@@ -33,6 +33,7 @@ lazy val root =
       `zio-quickstart-graphql-webservice`,
       `zio-quickstart-streams`,
       `zio-quickstart-encode-decode-json`,
+      `zio-quickstart-cache`,
       `zio-quickstart-prelude`
     )
 
@@ -49,4 +50,5 @@ lazy val `zio-quickstart-graphql-webservice`                  = project
 lazy val `zio-quickstart-streams`                             = project
 lazy val `zio-quickstart-encode-decode-json`                  = project
 lazy val `zio-quickstart-reloadable-services`                 = project
+lazy val `zio-quickstart-cache`                               = project
 lazy val `zio-quickstart-prelude`                             = project

zio-quickstart-cache/build.sbt

@@ -0,0 +1,3 @@
+scalaVersion := "2.13.13"
+
+libraryDependencies += "dev.zio" %% "zio-cache" % "0.2.3"

zio-quickstart-cache/src/main/scala/dev/zio/quickstart/CacheApp.scala

@@ -0,0 +1,43 @@
+package dev.zio.quickstart
+
+import zio._
+import zio.cache.{Cache, Lookup}
+import java.time.temporal.ChronoUnit
+
+object CacheApp extends ZIOAppDefault {
+  private val key = "key1"
+
+  private def timeConsumingEffect(key: String) =
+    ZIO.sleep(5.seconds).as(key.hashCode)
+
+  def run =
+    for {
+      cache <- Cache.make(
+        capacity = 100,
+        timeToLive = Duration.Infinity,
+        lookup = Lookup(timeConsumingEffect)
+      )
+      _         <- Console.printLine(s"Start getting results by $key:")
+      startTime <- Clock.currentTime(ChronoUnit.SECONDS)
+      result <- cache
+        .get(key)
+        .zipPar(cache.get(key))
+        .zipPar(cache.get(key))
+      endTime <- Clock.currentTime(ChronoUnit.SECONDS)
+      _ <- ZIO.debug(
+        s"Result of parallel execution of three effects with $key: $result"
+      )
+
+      hits                 <- cache.cacheStats.map(_.hits)
+      misses               <- cache.cacheStats.map(_.misses)
+      keyLastLoadedTimeOpt <- cache.entryStats(key)
+      keyLastLoadedTime    <- ZIO.fromOption(keyLastLoadedTimeOpt).map(_.loaded)
+      _                    <- ZIO.debug(s"Number of cache hits: $hits")
+      _                    <- ZIO.debug(s"Number of cache misses: $misses")
+      _ <- ZIO.debug(s"The last time of getting $key: $keyLastLoadedTime")
+      _ <- ZIO.debug(
+        s"Time to get result by $key 3 times: ${endTime - startTime} seconds"
+      )
+    } yield ()
+
+}