[FIX] Empty address handling

Author: Michal Mrozek

src/main/scala/io/iohk/ethereum/domain/Address.scala

@@ -31,7 +31,7 @@ object Address {
 
   def apply(hexString: String): Address = {
     val bytes = Hex.decode(hexString.replaceFirst("^0x", ""))
-    require(bytes.length <= Length, s"Invalid address: $hexString")
+    require(bytes.nonEmpty && bytes.length <= Length, s"Invalid address: $hexString")
     Address(bytes)
   }
 

src/main/scala/io/iohk/ethereum/jsonrpc/JsonMethodsImplicits.scala

@@ -94,15 +94,15 @@ trait JsonMethodsImplicits {
 
     for {
       from <- input.get("from") match {
-        case Some(JString(s)) => extractAddress(s)
+        case Some(JString(s)) if s.nonEmpty => extractAddress(s)
+        case Some(JString(_)) => extractAddress("0x0")
         case Some(_) => Left(InvalidAddress)
         case _ => Left(InvalidParams("TX 'from' is required"))
       }
 
       to <- input.get("to") match {
-        case Some(JString(s)) =>
-          extractAddress(s).map(Some(_))
-
+        case Some(JString(s)) if s.nonEmpty => extractAddress(s).map(Option.apply)
+        case Some(JString(_)) => extractAddress("0x0").map(Option.apply)
         case Some(_) => Left(InvalidAddress)
         case None => Right(None)
       }