diff --git a/README.md b/README.md
index 2083c46..040f8a4 100644
--- a/README.md
+++ b/README.md
@@ -12,3 +12,11 @@ Inspired by:
 - [Naivecoin](https://github.com/lhartikk/naivecoin) of [@lhartikk](https://github.com/lhartikk)
 
 REST API service is built on the open source projects [akka](https://github.com/akka/akka) and [akka-http](https://github.com/akka/akka-http).
+
+API Documentation on Postman: [blockchain-in-scala](https://documenter.getpostman.com/view/1231202/blockchain-in-scala/RVu8iTUP)
+
+Start the service, run this Class:
+
+```
+com.fluency03.blockchain.api.Server
+```
diff --git a/build.sbt b/build.sbt
index ebd2f83..5e54ee7 100644
--- a/build.sbt
+++ b/build.sbt
@@ -6,7 +6,7 @@ organization := "com.fluency03"
 
 name := "blockchain-in-scala"
 
-version := "0.0.2"
+version := "0.0.6"
 
 scalaVersion := "2.12.0"
 
@@ -43,3 +43,6 @@ libraryDependencies ++= {
       "org.bouncycastle" % "bcprov-jdk15on" % "1.59"
   )
 } ++ httpDependencies ++ testDependencies
+
+
+mainClass in assembly := Some("com.fluency03.blockchain.api.Server")
diff --git a/project/plugins.sbt b/project/plugins.sbt
index 5c39736..b34f37d 100644
--- a/project/plugins.sbt
+++ b/project/plugins.sbt
@@ -6,3 +6,4 @@ addSbtPlugin("org.scalastyle" %% "scalastyle-sbt-plugin" % "1.0.0")
 addSbtPlugin("com.artima.supersafe" %% "sbtplugin" % "1.1.3")
 addSbtPlugin("org.scoverage" % "sbt-scoverage" % "1.5.1")
 addSbtPlugin("org.scoverage" % "sbt-coveralls" % "1.2.4")
+addSbtPlugin("com.eed3si9n" % "sbt-assembly" % "0.14.6")
diff --git a/src/main/scala/com/fluency03/blockchain/api/actors/BlockchainActor.scala b/src/main/scala/com/fluency03/blockchain/api/actors/BlockchainActor.scala
index 2c0f293..99de84c 100644
--- a/src/main/scala/com/fluency03/blockchain/api/actors/BlockchainActor.scala
+++ b/src/main/scala/com/fluency03/blockchain/api/actors/BlockchainActor.scala
@@ -3,7 +3,9 @@ package com.fluency03.blockchain.api.actors
 import akka.actor.{ActorSelection, Props}
 import com.fluency03.blockchain.api.actors.BlockchainActor._
 import com.fluency03.blockchain.api._
-import com.fluency03.blockchain.core.Blockchain
+import com.fluency03.blockchain.core.{Block, Blockchain}
+
+import scala.collection.mutable
 
 object BlockchainActor {
   final case object GetBlockchain
@@ -23,6 +25,7 @@ class BlockchainActor extends ActorSupport {
 
   // TODO (Chang): need persistence
   var blockchainOpt: Option[Blockchain] = None
+  var hashIndexMapping = mutable.Map.empty[String, Int]
 
   def receive: Receive = {
     case GetBlockchain => onGetBlockchain()
@@ -31,6 +34,16 @@ class BlockchainActor extends ActorSupport {
     case _ => unhandled _
   }
 
+  /**
+   * TODO (Chang): new APIS:
+   *  - AddBlockOnBlockchain
+   *  - GetBlockFromBlockchain
+   *  - CheckBlockchainIsValid
+   *  - GetTransactionOfABlock
+   *  - MineNextBlock
+   *
+   */
+
   private def onGetBlockchain(): Unit = sender() ! blockchainOpt
 
   private def onCreateBlockchain(): Unit =
@@ -46,8 +59,5 @@ class BlockchainActor extends ActorSupport {
       sender() ! SuccessMsg(s"Blockchain deleted.")
     } else sender() ! FailureMsg(s"Blockchain does not exist.")
 
-  // TODO (Chang): APIs for adding new Block on the chain
-
-
 
 }
diff --git a/src/main/scala/com/fluency03/blockchain/api/actors/BlocksActor.scala b/src/main/scala/com/fluency03/blockchain/api/actors/BlocksActor.scala
index d03a204..a10b252 100644
--- a/src/main/scala/com/fluency03/blockchain/api/actors/BlocksActor.scala
+++ b/src/main/scala/com/fluency03/blockchain/api/actors/BlocksActor.scala
@@ -9,6 +9,7 @@ import scala.collection.mutable
 
 object BlocksActor {
   final case object GetBlocks
+  final case class GetBlocks(hashes: Set[String])
   final case class CreateBlock(block: Block)
   final case class GetBlock(hash: String)
   final case class DeleteBlock(hash: String)
@@ -25,35 +26,48 @@ class BlocksActor extends ActorSupport {
   val transActor: ActorSelection = context.actorSelection(PARENT_UP + TRANS_ACTOR_NAME)
 
   // TODO (Chang): need persistence
-  var blocks = mutable.Map.empty[String, Block]
+  var blocksPool = mutable.Map.empty[String, Block]
 
   def receive: Receive = {
     case GetBlocks => onGetBlocks()
+    case GetBlocks(hashes) => onGetBlocks(hashes)
     case CreateBlock(block) => onCreateBlock(block)
     case GetBlock(hash) => onGetBlock(hash)
     case DeleteBlock(hash) => onDeleteBlock(hash)
     case _ => unhandled _
   }
 
-  private[this] def onGetBlocks(): Unit = sender() ! blocks.values.toSeq
+  /**
+   * TODO (Chang): new APIS:
+   *  - CreateBlock
+   *  - GetBlock (onChain or offChain)
+   *  - GetTransactionOfABlock
+   *  - AddBlockOnChain
+   *
+   */
+
+  private[this] def onGetBlocks(): Unit = sender() ! blocksPool.values.toSeq
+
+  private[this] def onGetBlocks(hashes: Set[String]): Unit = sender() ! blocksPool.filterKeys(
+    k => hashes.contains(k)
+  ).values.toSeq
 
   private[this] def onCreateBlock(block: Block): Unit = {
-    if (blocks.contains(block.hash)) sender() ! FailureMsg(s"Block ${block.hash} already exists.")
+    if (blocksPool.contains(block.hash)) sender() ! FailureMsg(s"Block ${block.hash} already exists.")
     else {
-      blocks += (block.hash -> block)
+      blocksPool += (block.hash -> block)
       sender() ! SuccessMsg(s"Block ${block.hash} created.")
     }
   }
 
-  private[this] def onGetBlock(hash: String): Unit = sender() ! blocks.get(hash)
+  private[this] def onGetBlock(hash: String): Unit = sender() ! blocksPool.get(hash)
 
   private[this] def onDeleteBlock(hash: String): Unit = {
-    if (blocks.contains(hash)) {
-      blocks -= hash
+    if (blocksPool.contains(hash)) {
+      blocksPool -= hash
       sender() ! SuccessMsg(s"Block $hash deleted.")
     } else sender() ! FailureMsg(s"Block $hash does not exist.")
   }
 
 
-
 }
diff --git a/src/main/scala/com/fluency03/blockchain/api/actors/NetworkActor.scala b/src/main/scala/com/fluency03/blockchain/api/actors/NetworkActor.scala
index 3b0b838..c953beb 100644
--- a/src/main/scala/com/fluency03/blockchain/api/actors/NetworkActor.scala
+++ b/src/main/scala/com/fluency03/blockchain/api/actors/NetworkActor.scala
@@ -7,8 +7,12 @@ import com.fluency03.blockchain.api.actors.NetworkActor._
 import com.fluency03.blockchain.api.actors.PeerActor.GetPublicKeys
 import com.fluency03.blockchain.core.Peer
 
+import scala.concurrent.Future
+
 object NetworkActor {
+  final case object GetNetwork
   final case object GetPeers
+  final case class GetPeers(names: Set[String])
   final case class CreatePeer(name: String)
   final case class GetPeer(name: String)
   final case class DeletePeer(name: String)
@@ -28,15 +32,33 @@ class NetworkActor extends ActorSupport {
 
   // TODO (Chang): need persistence
 
+  /**
+   * TODO (Chang):
+   *  - Remove wallet
+   *  - Sign transaction
+   *
+   */
+
   def receive: Receive = {
+    case GetNetwork => onGetNetwork()
     case GetPeers => onGetPeers()
+    case GetPeers(names) => onGetPeers(names)
     case CreatePeer(name) => onCreatePeer(name)
     case GetPeer(name) => onGetPeer(name)
     case DeletePeer(name) => onDeletePeer(name)
     case _ => unhandled _
   }
 
-  private def onGetPeers(): Unit = sender() ! context.children.map(_.path.name).toSet
+  private def onGetNetwork(): Unit = sender() ! context.children.map(_.path.name).toSet
+
+  private def onGetPeers(): Unit = Future.sequence(context.children.map(p => {
+    (p ? GetPublicKeys).mapTo[Set[String]].map(keys => p.path.name -> keys)
+  })).map(_.toMap).pipeTo(sender())
+
+  private def onGetPeers(names: Set[String]): Unit = Future.sequence(context.children
+    .filter(p => names.contains(p.path.name))
+    .map(p => { (p ? GetPublicKeys).mapTo[Set[String]].map(keys => p.path.name -> keys) })
+  ).map(_.toMap).pipeTo(sender())
 
   private def onCreatePeer(name: String): Unit =
     if (context.child(name).isDefined) sender() ! FailureMsg(s"Peer $name has been created.")
@@ -59,8 +81,4 @@ class NetworkActor extends ActorSupport {
       sender() ! SuccessMsg(s"Peer $name deleted.")
     } else sender() ! FailureMsg(s"Peer $name does not exist.")
 
-  // TODO (Chang): APIs for selecting Peers based on Seq of ids
-
-
-
 }
diff --git a/src/main/scala/com/fluency03/blockchain/api/actors/PeerActor.scala b/src/main/scala/com/fluency03/blockchain/api/actors/PeerActor.scala
index bcde51b..92b1d2d 100644
--- a/src/main/scala/com/fluency03/blockchain/api/actors/PeerActor.scala
+++ b/src/main/scala/com/fluency03/blockchain/api/actors/PeerActor.scala
@@ -27,6 +27,13 @@ class PeerActor extends ActorSupport {
   val wallets = mutable.Map.empty[String, Wallet]
   val others = mutable.Map.empty[String, Peer]
 
+  /**
+   * TODO (Chang):
+   *  - Remove wallet
+   *  - Sign transactions
+   *
+   */
+
   def receive: Receive = {
     case GetPublicKeys => sender() ! wallets.values.map(_.address).toSet
     case CreateWallet => sender() ! addWallet()
diff --git a/src/main/scala/com/fluency03/blockchain/api/actors/TransactionsActor.scala b/src/main/scala/com/fluency03/blockchain/api/actors/TransactionsActor.scala
index d6e273d..1fc0699 100644
--- a/src/main/scala/com/fluency03/blockchain/api/actors/TransactionsActor.scala
+++ b/src/main/scala/com/fluency03/blockchain/api/actors/TransactionsActor.scala
@@ -9,9 +9,10 @@ import scala.collection.mutable
 
 object TransactionsActor {
   final case object GetTransactions
+  final case class GetTransactions(ids: Set[String])
   final case class CreateTransaction(tx: Transaction)
-  final case class GetTransaction(hash: String)
-  final case class DeleteTransaction(hash: String)
+  final case class GetTransaction(id: String)
+  final case class DeleteTransaction(id: String)
 
   def props: Props = Props[TransactionsActor]
 }
@@ -21,40 +22,49 @@ class TransactionsActor extends ActorSupport {
   override def postStop(): Unit = log.info("{} stopped!", this.getClass.getSimpleName)
 
   // TODO (Chang): need persistence
-  val currentTransactions: mutable.Map[String, Transaction] = mutable.Map.empty[String, Transaction]
+  val transPool: mutable.Map[String, Transaction] = mutable.Map.empty[String, Transaction]
   val uTxOs: mutable.Map[Outpoint, TxOut] = mutable.Map.empty[Outpoint, TxOut]
 
   val blockchainActor: ActorSelection = context.actorSelection(PARENT_UP + BLOCKCHAIN_ACTOR_NAME)
   val blockActor: ActorSelection = context.actorSelection(PARENT_UP + BLOCKS_ACTOR_NAME)
   val networkActor: ActorSelection = context.actorSelection(PARENT_UP + NETWORK_ACTOR_NAME)
 
+  /**
+   * TODO (Chang):
+   *  - Update transaction
+   *  - Sign transaction
+   *
+   */
+
   def receive: Receive = {
     case GetTransactions => onGetTransactions()
+    case GetTransactions(ids) => onGetTransactions(ids)
     case CreateTransaction(tx) => onCreateTransaction(tx)
-    case GetTransaction(hash) => onGetTransaction(hash)
-    case DeleteTransaction(hash) => onDeleteTransaction(hash)
+    case GetTransaction(id) => onGetTransaction(id)
+    case DeleteTransaction(id) => onDeleteTransaction(id)
     case _ => unhandled _
   }
 
-  private def onGetTransactions(): Unit = sender() ! currentTransactions.values.toSeq
+  private def onGetTransactions(): Unit = sender() ! transPool.values.toSeq
+
+  private def onGetTransactions(ids: Set[String]): Unit = sender() ! transPool.filterKeys(
+    k => ids.contains(k)
+  ).values.toSeq
 
   private def onCreateTransaction(tx: Transaction): Unit = {
-    if (currentTransactions.contains(tx.id)) sender() ! FailureMsg(s"Transaction ${tx.id} already exists.")
+    if (transPool.contains(tx.id)) sender() ! FailureMsg(s"Transaction ${tx.id} already exists.")
     else {
-      currentTransactions += (tx.id -> tx)
+      transPool += (tx.id -> tx)
       sender() ! SuccessMsg(s"Transaction ${tx.id} created.")
     }
   }
 
-  private def onGetTransaction(id: String): Unit = sender() ! currentTransactions.get(id)
+  private def onGetTransaction(id: String): Unit = sender() ! transPool.get(id)
 
   private def onDeleteTransaction(id: String): Unit =
-    if (currentTransactions contains id) {
-      currentTransactions -= id
+    if (transPool contains id) {
+      transPool -= id
       sender() ! SuccessMsg(s"Transaction $id deleted.")
     } else sender() ! FailureMsg(s"Transaction $id does not exist.")
 
-  // TODO (Chang): APIs for selecting transactions based on Seq of ids
-
-
 }
diff --git a/src/main/scala/com/fluency03/blockchain/api/routes/BlockRoutes.scala b/src/main/scala/com/fluency03/blockchain/api/routes/BlockRoutes.scala
index 172f9d8..d3b1351 100644
--- a/src/main/scala/com/fluency03/blockchain/api/routes/BlockRoutes.scala
+++ b/src/main/scala/com/fluency03/blockchain/api/routes/BlockRoutes.scala
@@ -2,14 +2,14 @@ package com.fluency03.blockchain.api.routes
 
 import akka.actor.ActorRef
 import akka.event.Logging
-import akka.http.scaladsl.model.StatusCodes
 import akka.http.scaladsl.server.Directives._
 import akka.http.scaladsl.server.Route
 import akka.http.scaladsl.server.directives.MethodDirectives.{delete, get, post}
 import akka.http.scaladsl.server.directives.PathDirectives.path
 import akka.http.scaladsl.server.directives.RouteDirectives.complete
+import akka.http.scaladsl.unmarshalling.PredefinedFromStringUnmarshallers.CsvSeq
 import akka.pattern.ask
-import com.fluency03.blockchain.api.{Blocks, FailureMsg, Message, SuccessMsg}
+import com.fluency03.blockchain.api.{Blocks, Message}
 import com.fluency03.blockchain.api.actors.BlocksActor._
 import com.fluency03.blockchain.core.Block
 
@@ -20,10 +20,21 @@ trait BlockRoutes extends RoutesSupport {
 
   def blocksActor: ActorRef
 
+  /**
+   * TODO (Chang): new APIS:
+   *  - CreateBlock
+   *  - GetBlock (onChain or offChain)
+   *  - GetTransactionOfABlock
+   *  - AddBlockOnChain
+   *
+   */
+
   lazy val blockRoutes: Route =
     path(BLOCKS) {
-      get {
-        val blocks: Future[Blocks] = (blocksActor ? GetBlocks).mapTo[Blocks]
+      parameters( 'hashes.as(CsvSeq[String]) ? ) { hashes =>
+        val blocks: Future[Blocks] =
+          if (hashes.isDefined) (blocksActor ? GetBlocks(hashes.get.toSet)).mapTo[Blocks]
+          else (blocksActor ? GetBlocks).mapTo[Blocks]
         complete(blocks)
       }
     } ~
diff --git a/src/main/scala/com/fluency03/blockchain/api/routes/BlockchainRoutes.scala b/src/main/scala/com/fluency03/blockchain/api/routes/BlockchainRoutes.scala
index fb0ef81..c32da2c 100644
--- a/src/main/scala/com/fluency03/blockchain/api/routes/BlockchainRoutes.scala
+++ b/src/main/scala/com/fluency03/blockchain/api/routes/BlockchainRoutes.scala
@@ -18,6 +18,16 @@ trait BlockchainRoutes extends RoutesSupport {
 
   def blockchainActor: ActorRef
 
+  /**
+   * TODO (Chang): new APIS:
+   *  - AddBlockOnBlockchain
+   *  - GetBlockFromBlockchain
+   *  - CheckBlockchainIsValid
+   *  - GetTransactionOfABlock
+   *  - MineNextBlock
+   *
+   */
+
   lazy val blockchainRoutes: Route =
     pathPrefix(BLOCKCHAIN) {
       pathEnd {
diff --git a/src/main/scala/com/fluency03/blockchain/api/routes/NetworkRoutes.scala b/src/main/scala/com/fluency03/blockchain/api/routes/NetworkRoutes.scala
index 64991df..d4f301a 100644
--- a/src/main/scala/com/fluency03/blockchain/api/routes/NetworkRoutes.scala
+++ b/src/main/scala/com/fluency03/blockchain/api/routes/NetworkRoutes.scala
@@ -2,15 +2,15 @@ package com.fluency03.blockchain.api.routes
 
 import akka.actor.ActorRef
 import akka.event.Logging
-import akka.http.scaladsl.model.StatusCodes
 import akka.http.scaladsl.server.Directives._
 import akka.http.scaladsl.server.Route
 import akka.http.scaladsl.server.directives.MethodDirectives.{delete, get, post}
 import akka.http.scaladsl.server.directives.PathDirectives.path
 import akka.http.scaladsl.server.directives.RouteDirectives.complete
+import akka.http.scaladsl.unmarshalling.PredefinedFromStringUnmarshallers.CsvSeq
 import akka.pattern.ask
-import com.fluency03.blockchain.api.actors.NetworkActor.{CreatePeer, DeletePeer, GetPeer, GetPeers}
-import com.fluency03.blockchain.api.{FailureMsg, Message, SuccessMsg}
+import com.fluency03.blockchain.api.Message
+import com.fluency03.blockchain.api.actors.NetworkActor._
 import com.fluency03.blockchain.core.{Peer, PeerSimple}
 
 import scala.concurrent.Future
@@ -20,11 +20,27 @@ trait NetworkRoutes extends RoutesSupport {
 
   def networkActor: ActorRef
 
+  /**
+   * TODO (Chang):
+   *  - Sign transaction
+   *
+   */
+
   lazy val networkRoutes: Route =
+    path(NETWORK) {
+      get {
+        val network: Future[Set[String]] = (networkActor ? GetNetwork).mapTo[Set[String]]
+        complete(network)
+      }
+    } ~
     path(PEERS) {
       get {
-        val peers: Future[Set[String]] = (networkActor ? GetPeers).mapTo[Set[String]]
-        complete(peers)
+        parameters( 'names.as(CsvSeq[String]) ? ) { names =>
+          val peers: Future[Map[String, Set[String]]] =
+            if (names.isDefined) (networkActor ? GetPeers(names.get.toSet)).mapTo[Map[String, Set[String]]]
+            else (networkActor ? GetPeers).mapTo[Map[String, Set[String]]]
+          complete(peers)
+        }
       }
     } ~
     pathPrefix(PEER) {
@@ -41,10 +57,10 @@ trait NetworkRoutes extends RoutesSupport {
           val maybePeer: Future[Option[Peer]] = (networkActor ? GetPeer(name)).mapTo[Option[Peer]]
           rejectEmptyResponse { complete(maybePeer) }
         } ~
-          delete {
-            val peerDeleted: Future[Message] = (networkActor ? DeletePeer(name)).mapTo[Message]
-            onSuccess(peerDeleted) { respondOnDeletion }
-          }
+        delete {
+          val peerDeleted: Future[Message] = (networkActor ? DeletePeer(name)).mapTo[Message]
+          onSuccess(peerDeleted) { respondOnDeletion }
+        }
       }
     }
 
diff --git a/src/main/scala/com/fluency03/blockchain/api/routes/TransactionRoutes.scala b/src/main/scala/com/fluency03/blockchain/api/routes/TransactionRoutes.scala
index 3f241b2..4f63ace 100644
--- a/src/main/scala/com/fluency03/blockchain/api/routes/TransactionRoutes.scala
+++ b/src/main/scala/com/fluency03/blockchain/api/routes/TransactionRoutes.scala
@@ -2,15 +2,15 @@ package com.fluency03.blockchain.api.routes
 
 import akka.actor.ActorRef
 import akka.event.Logging
-import akka.http.scaladsl.model.StatusCodes
 import akka.http.scaladsl.server.Directives._
 import akka.http.scaladsl.server.Route
 import akka.http.scaladsl.server.directives.MethodDirectives.{delete, get, post}
 import akka.http.scaladsl.server.directives.PathDirectives.path
 import akka.http.scaladsl.server.directives.RouteDirectives.complete
+import akka.http.scaladsl.unmarshalling.PredefinedFromStringUnmarshallers.CsvSeq
 import akka.pattern.ask
-import com.fluency03.blockchain.api.{FailureMsg, Message, SuccessMsg, Transactions}
 import com.fluency03.blockchain.api.actors.TransactionsActor._
+import com.fluency03.blockchain.api.{Message, Transactions}
 import com.fluency03.blockchain.core.Transaction
 
 import scala.concurrent.Future
@@ -20,10 +20,19 @@ trait TransactionRoutes extends RoutesSupport {
 
   def transActor: ActorRef
 
+  /**
+   * TODO (Chang):
+   *  - Update transaction
+   *  - Sign transaction
+   *
+   */
+
   lazy val transRoutes: Route =
     path(TRANSACTIONS) {
-      get {
-        val transactions: Future[Transactions] = (transActor ? GetTransactions).mapTo[Transactions]
+      parameters( 'ids.as(CsvSeq[String]) ? ) { ids =>
+        val transactions: Future[Transactions] =
+          if (ids.isDefined) (transActor ? GetTransactions(ids.get.toSet)).mapTo[Transactions]
+          else (transActor ? GetTransactions).mapTo[Transactions]
         complete(transactions)
       }
     } ~
diff --git a/src/main/scala/com/fluency03/blockchain/api/routes/package.scala b/src/main/scala/com/fluency03/blockchain/api/routes/package.scala
index 29d2cbd..8990774 100644
--- a/src/main/scala/com/fluency03/blockchain/api/routes/package.scala
+++ b/src/main/scala/com/fluency03/blockchain/api/routes/package.scala
@@ -21,6 +21,7 @@ package object routes {
   val BLOCK = "block"
 
   // network
+  val NETWORK = "network"
   val PEERS = "peers"
   val PEER = "peer"
 
diff --git a/src/main/scala/com/fluency03/blockchain/core/Peer.scala b/src/main/scala/com/fluency03/blockchain/core/Peer.scala
index 94e2f9b..69c24fb 100644
--- a/src/main/scala/com/fluency03/blockchain/core/Peer.scala
+++ b/src/main/scala/com/fluency03/blockchain/core/Peer.scala
@@ -1,7 +1,4 @@
 package com.fluency03.blockchain.core
 
-trait PeerSimple {
-  def name: String
-}
-
-case class Peer(name: String, publicKeys: Set[String]) extends PeerSimple
+case class PeerSimple(name: String)
+case class Peer(name: String, publicKeys: Set[String])
diff --git a/src/main/scala/com/fluency03/blockchain/package.scala b/src/main/scala/com/fluency03/blockchain/package.scala
index f5046cb..d947e31 100644
--- a/src/main/scala/com/fluency03/blockchain/package.scala
+++ b/src/main/scala/com/fluency03/blockchain/package.scala
@@ -5,10 +5,10 @@ import java.security.{MessageDigest, PrivateKey, PublicKey}
 import java.time.Instant
 
 import com.fluency03.blockchain.Crypto.{privateKeyToHex, publicKeyToHex}
-import com.fluency03.blockchain.core.{TxIn, TxOut}
+import com.fluency03.blockchain.core.{Peer, PeerSimple, TxIn, TxOut}
 import org.bouncycastle.util.encoders.{Base64, Hex}
-import org.json4s.{Formats, NoTypeHints}
 import org.json4s.native.Serialization
+import org.json4s.{Formats, NoTypeHints}
 
 import scala.io.Source
 
@@ -52,6 +52,10 @@ package object blockchain {
     def toHex: String = privateKeyToHex(privateKey)
   }
 
+  implicit class PeerImplicit(val peer: Peer) {
+    def toSimple: PeerSimple = PeerSimple(peer.name)
+  }
+
 
   /**
    * Generate SHA256 Hash from a input String.
diff --git a/src/test/scala/com/fluency03/blockchain/api/actors/BlocksActorTest.scala b/src/test/scala/com/fluency03/blockchain/api/actors/BlocksActorTest.scala
index 958751c..ee51ed5 100644
--- a/src/test/scala/com/fluency03/blockchain/api/actors/BlocksActorTest.scala
+++ b/src/test/scala/com/fluency03/blockchain/api/actors/BlocksActorTest.scala
@@ -23,6 +23,9 @@ class BlocksActorTest extends TestKit(ActorSystem("BlocksActorTest")) with Impli
       blocksActor ! GetBlocks
       expectMsg(Seq.empty[Block])
 
+      blocksActor ! GetBlocks(Set("somehash"))
+      expectMsg(Seq.empty[Block])
+
       blocksActor ! CreateBlock(Block.genesisBlock)
       expectMsg(SuccessMsg(s"Block ${Block.genesisBlock.hash} created."))
 
@@ -32,6 +35,12 @@ class BlocksActorTest extends TestKit(ActorSystem("BlocksActorTest")) with Impli
       blocksActor ! GetBlocks
       expectMsg(Seq(Block.genesisBlock))
 
+      blocksActor ! GetBlocks(Set("somehash"))
+      expectMsg(Seq.empty[Block])
+
+      blocksActor ! GetBlocks(Set(Block.genesisBlock.hash))
+      expectMsg(Seq(Block.genesisBlock))
+
       blocksActor ! GetBlock(Block.genesisBlock.hash)
       expectMsg(Some(Block.genesisBlock))
 
diff --git a/src/test/scala/com/fluency03/blockchain/api/actors/NetworkActorTest.scala b/src/test/scala/com/fluency03/blockchain/api/actors/NetworkActorTest.scala
index 7b4116a..2e78763 100644
--- a/src/test/scala/com/fluency03/blockchain/api/actors/NetworkActorTest.scala
+++ b/src/test/scala/com/fluency03/blockchain/api/actors/NetworkActorTest.scala
@@ -20,9 +20,15 @@ class NetworkActorTest extends TestKit(ActorSystem("NetworkActorTest")) with Imp
     "Respond with a Set of Peers." in {
       NetworkActor.props shouldEqual Props[NetworkActor]
 
-      networkActor ! GetPeers
+      networkActor ! GetNetwork
       expectMsg(Set.empty[String])
 
+      networkActor ! GetPeers
+      expectMsg(Map.empty[String, Set[String]])
+
+      networkActor ! GetPeers(Set("somename"))
+      expectMsg(Map.empty[String, Set[String]])
+
       val name = "peer"
       networkActor ! CreatePeer(name)
       expectMsg(SuccessMsg(s"Peer $name created."))
@@ -30,9 +36,22 @@ class NetworkActorTest extends TestKit(ActorSystem("NetworkActorTest")) with Imp
       networkActor ! CreatePeer(name)
       expectMsg(FailureMsg(s"Peer $name has been created."))
 
-      networkActor ! GetPeers
+      networkActor ! GetNetwork
       expectMsg(Set(name))
 
+      networkActor ! GetPeers
+      val peers = expectMsgType[Map[String, Set[String]]]
+      peers.size shouldEqual 1
+      peers.contains(name) shouldEqual true
+      peers(name).size shouldEqual 1
+
+      networkActor ! GetPeers(Set("somename"))
+      expectMsg(Map.empty[String, Set[String]])
+
+      networkActor ! GetPeers(Set(name))
+      val peers2 = expectMsgType[Map[String, Set[String]]]
+      peers2 shouldEqual peers
+
       networkActor ! GetPeer(name)
       val peerOpt = expectMsgType[Some[Peer]]
       peerOpt.isDefined shouldEqual true
diff --git a/src/test/scala/com/fluency03/blockchain/api/actors/TransactionsActorTest.scala b/src/test/scala/com/fluency03/blockchain/api/actors/TransactionsActorTest.scala
index 5bc716d..d0162e6 100644
--- a/src/test/scala/com/fluency03/blockchain/api/actors/TransactionsActorTest.scala
+++ b/src/test/scala/com/fluency03/blockchain/api/actors/TransactionsActorTest.scala
@@ -25,6 +25,9 @@ class TransactionsActorTest extends TestKit(ActorSystem("TransactionsActorTest")
       transActor ! GetTransactions
       expectMsg(Seq.empty[Transaction])
 
+      transActor ! GetTransactions(Set("someid"))
+      expectMsg(Seq.empty[Transaction])
+
       val genesisTx: Transaction = createCoinbaseTx(0, genesisMiner, genesisTimestamp)
       transActor ! CreateTransaction(genesisTx)
       expectMsg(SuccessMsg(s"Transaction ${genesisTx.id} created."))
@@ -35,6 +38,12 @@ class TransactionsActorTest extends TestKit(ActorSystem("TransactionsActorTest")
       transActor ! GetTransactions
       expectMsg(Seq(genesisTx))
 
+      transActor ! GetTransactions(Set("someid"))
+      expectMsg(Seq.empty[Transaction])
+
+      transActor ! GetTransactions(Set(genesisTx.id))
+      expectMsg(Seq(genesisTx))
+
       transActor ! GetTransaction(genesisTx.id)
       expectMsg(Some(genesisTx))
 
diff --git a/src/test/scala/com/fluency03/blockchain/api/routes/BlockRoutesTest.scala b/src/test/scala/com/fluency03/blockchain/api/routes/BlockRoutesTest.scala
index 486af66..aff84b5 100644
--- a/src/test/scala/com/fluency03/blockchain/api/routes/BlockRoutesTest.scala
+++ b/src/test/scala/com/fluency03/blockchain/api/routes/BlockRoutesTest.scala
@@ -1,8 +1,9 @@
 package com.fluency03.blockchain.api.routes
 
 import akka.http.scaladsl.testkit.ScalatestRouteTest
+import com.fluency03.blockchain.api.JsonSupport
 import org.scalatest.{Matchers, WordSpec}
 
-class BlockRoutesTest extends WordSpec with Matchers with ScalatestRouteTest {
+class BlockRoutesTest extends WordSpec with Matchers with ScalatestRouteTest with JsonSupport {
 
 }
diff --git a/src/test/scala/com/fluency03/blockchain/api/routes/BlockchainRoutesTest.scala b/src/test/scala/com/fluency03/blockchain/api/routes/BlockchainRoutesTest.scala
index 2b8a8a1..ed3a460 100644
--- a/src/test/scala/com/fluency03/blockchain/api/routes/BlockchainRoutesTest.scala
+++ b/src/test/scala/com/fluency03/blockchain/api/routes/BlockchainRoutesTest.scala
@@ -1,9 +1,10 @@
 package com.fluency03.blockchain.api.routes
 
 import akka.http.scaladsl.testkit.ScalatestRouteTest
+import com.fluency03.blockchain.api.JsonSupport
 import org.scalatest.{Matchers, WordSpec}
 
-class BlockchainRoutesTest extends WordSpec with Matchers with ScalatestRouteTest {
+class BlockchainRoutesTest extends WordSpec with Matchers with ScalatestRouteTest with JsonSupport {
 
 
 
diff --git a/src/test/scala/com/fluency03/blockchain/api/routes/NetworkRoutesTest.scala b/src/test/scala/com/fluency03/blockchain/api/routes/NetworkRoutesTest.scala
index f5f013d..28e9567 100644
--- a/src/test/scala/com/fluency03/blockchain/api/routes/NetworkRoutesTest.scala
+++ b/src/test/scala/com/fluency03/blockchain/api/routes/NetworkRoutesTest.scala
@@ -1,8 +1,9 @@
 package com.fluency03.blockchain.api.routes
 
 import akka.http.scaladsl.testkit.ScalatestRouteTest
+import com.fluency03.blockchain.api.JsonSupport
 import org.scalatest.{Matchers, WordSpec}
 
-class NetworkRoutesTest extends WordSpec with Matchers with ScalatestRouteTest {
+class NetworkRoutesTest extends WordSpec with Matchers with ScalatestRouteTest with JsonSupport {
 
 }
diff --git a/src/test/scala/com/fluency03/blockchain/api/routes/TransactionRoutesTest.scala b/src/test/scala/com/fluency03/blockchain/api/routes/TransactionRoutesTest.scala
index 7788748..6dbe8cc 100644
--- a/src/test/scala/com/fluency03/blockchain/api/routes/TransactionRoutesTest.scala
+++ b/src/test/scala/com/fluency03/blockchain/api/routes/TransactionRoutesTest.scala
@@ -1,8 +1,9 @@
 package com.fluency03.blockchain.api.routes
 
 import akka.http.scaladsl.testkit.ScalatestRouteTest
+import com.fluency03.blockchain.api.JsonSupport
 import org.scalatest.{Matchers, WordSpec}
 
-class TransactionRoutesTest extends WordSpec with Matchers with ScalatestRouteTest {
+class TransactionRoutesTest extends WordSpec with Matchers with ScalatestRouteTest with JsonSupport {
 
 }
diff --git a/src/test/scala/com/fluency03/blockchain/core/PeerTest.scala b/src/test/scala/com/fluency03/blockchain/core/PeerTest.scala
index c95d101..619c589 100644
--- a/src/test/scala/com/fluency03/blockchain/core/PeerTest.scala
+++ b/src/test/scala/com/fluency03/blockchain/core/PeerTest.scala
@@ -8,8 +8,11 @@ class PeerTest extends FlatSpec with Matchers {
     val p = Peer("peer", Set("abcd"))
     p.name shouldEqual "peer"
     p.publicKeys shouldEqual Set("abcd")
-    p shouldBe a[PeerSimple]
     p shouldBe a[Peer]
+    p should not be a[PeerSimple]
+    val ps = p.toSimple
+    ps shouldBe a[PeerSimple]
+    ps.name shouldEqual "peer"
   }
 
 }