server: Add endpoint "POST /transactions/latest"

This retrieves the latest transaction id for the given addresses.

server/app/com/xsn/explorer/services/TransactionService.scala

@@ -114,6 +114,11 @@ class TransactionService @Inject() (
 
     result.toFuture
   }
+
+  def getLatestTransactionBy(addresses: List[Address]): FutureApplicationResult[Map[String, String]] = {
+    transactionFutureDataHandler.getLatestTransactionBy(addresses)
+  }
+
   private def getTransactionValue(vin: TransactionVIN): FutureApplicationResult[TransactionValue] = {
     val valueMaybe = for {
       value <- vin.value

server/app/controllers/TransactionsController.scala

@@ -3,6 +3,7 @@ package controllers
 import javax.inject.Inject
 
 import com.alexitc.playsonify.models.PublicContextWithModel
+import com.xsn.explorer.models.Address
 import com.xsn.explorer.models.request.SendRawTransactionRequest
 import com.xsn.explorer.services.TransactionService
 import controllers.common.{MyJsonController, MyJsonControllerComponents}
@@ -23,4 +24,8 @@ class TransactionsController @Inject() (
   def sendRawTransaction() = publicWithInput { ctx: PublicContextWithModel[SendRawTransactionRequest] =>
     transactionService.sendRawTransaction(ctx.model.hex)
   }
+
+  def getLatestByAddresses() = publicWithInput { ctx: PublicContextWithModel[List[Address]] =>
+    transactionService.getLatestTransactionBy(ctx.model)
+  }
 }

server/conf/routes

@@ -8,6 +8,7 @@ GET   /health                controllers.HealthController.check()
 GET   /transactions/:txid        controllers.TransactionsController.getTransaction(txid: String)
 GET   /transactions/:txid/raw    controllers.TransactionsController.getRawTransaction(txid: String)
 POST  /transactions              controllers.TransactionsController.sendRawTransaction()
+POST  /transactions/latest       controllers.TransactionsController.getLatestByAddresses()
 
 GET   /addresses/:address                 controllers.AddressesController.getBy(address: String)
 GET   /addresses/:address/transactions    controllers.AddressesController.getTransactions(address: String, offset: Int ?= 0, limit: Int ?= 10, orderBy: String ?= "")