use http client from play, which is called WS

.gitignore

@@ -2,3 +2,4 @@
 .ensime_cache
 target
 *.class
+*.log

src/main/scala/net/hiogawa/playground/ws/IndependentClient.scala

@@ -0,0 +1,27 @@
+package net.hiogawa.playground.ws
+
+// java
+import com.ning.http.client.AsyncHttpClientConfig
+
+// scala
+import scala.concurrent.Future
+import play.api.libs.ws.{WS, WSClient, WSResponse}
+import play.api.libs.ws.ning.NingWSClient
+
+// implicits
+import scala.concurrent.ExecutionContext.Implicits.global // ExecutionContext
+
+
+object IndependentClient {
+
+  def getNonBlockWithClient(url : String)(implicit c : WSClient) : Future[String] = {
+    WS.clientUrl(url).get() map (resp => resp.body)
+  }
+
+  // NOTE: implicit val implicitClient = IndependentClient.makeDummyClient
+  def makeDummyClient : NingWSClient = {
+    val builder = new AsyncHttpClientConfig.Builder()
+    val client = new NingWSClient(builder.build())
+    client
+  }
+}

src/main/scala/net/hiogawa/playground/ws/WSStuff.scala

@@ -0,0 +1,31 @@
+package net.hiogawa.playground.ws
+
+import scala.concurrent.Future
+import play.api.libs.ws.{WS, WSResponse}
+
+// implicits
+import scala.concurrent.ExecutionContext.Implicits.global // ExecutionContext
+import play.api.Play.current // Application
+
+
+object WSStuff {
+
+  def getNonBlock(url : String) : Future[String] = {
+    WS.url(url).get() map (resp => resp.body)
+  }
+
+  def getParallelAndProcess[T](urls : List[String])(f : WSResponse => T) : Future[List[T]] = {
+    sequence(urls.map((url) => WS.url(url).get() map f))
+  }
+
+  // TODO: use applicative from scalaz
+  // cf. https://www.haskell.org/hoogle/?hoogle=sequence
+  def sequence[T](ms : List[Future[T]]) : Future[List[T]] = {
+    ms.foldLeft[Future[List[T]]](Future(List.empty))((accFutures, future) =>
+      for {
+        accResps <- accFutures
+        resp <- future
+      } yield (resp :: accResps)
+    )
+  }
+}

src/test/scala/net/hiogawa/playground/ws/IndependentClientTest.scala

@@ -0,0 +1,23 @@
+package net.hiogawa.playground.ws
+
+import org.specs2.mutable._
+
+import scala.concurrent.Await
+import scala.concurrent.duration.Duration
+
+class IndependentClientTest extends Specification {
+
+  "IndependentClient" >> {
+
+
+    // TODO: how to inject implicit declaration as an before all context or anything
+    //       https://etorreborre.github.io/specs2/guide/SPECS2-3.6.5/org.specs2.guide.ContextObjects.html
+    "getNonBlock" >> {
+      implicit val implicitClient = IndependentClient.makeDummyClient
+      val f = IndependentClient.getNonBlockWithClient("http://stackoverflow.com/questions/24881145/how-do-i-use-play-ws-library-in-normal-sbt-project-instead-of-play")
+      Await.result(f.map((body) => {body.substring(0, 100).length}), Duration.Inf) must be_==(100)
+      implicitClient.close()
+      true
+    }
+  }
+}

src/test/scala/net/hiogawa/playground/ws/WSStuffTest.scala

@@ -0,0 +1,29 @@
+package net.hiogawa.playground.ws
+
+import org.specs2.mutable._
+import play.api.test.{FakeApplication, WithApplication}
+
+import scala.concurrent.Await
+import scala.concurrent.duration.Duration
+
+// implicits
+import scala.concurrent.ExecutionContext.Implicits.global
+
+class WSStuffTest extends Specification {
+
+  "WSStuff" >> {
+
+    ".getParallelAndProcess" in new WithApplication(new FakeApplication) {
+      val urls = List(
+        "http://stackoverflow.com/questions/33718775/changing-bootstrap-btn-css-and-hover-action-issue",
+        "http://stackoverflow.com/questions/33718719/github-hot-to-avoid-exceeding-search-limit-while-searching-for-accounts-detail",
+        "http://stackoverflow.com/questions/33718754/my-javascript-script-for-changing-css-dont-seem-to-be-workin"
+      )
+      // NOTE: you would see output order is defferent between each test run
+      Await.result(WSStuff.getParallelAndProcess(urls){(resp) =>
+        println("-----------")
+        println(resp.body.substring(0, 200))
+      }, Duration.Inf).length must be_==(3)
+    }
+  }
+}