server: Add unique constraint to the blocks table

This also changes the upsert method to insert on the BlockDataHandler,
this is piece for fixing the bug #6

server/app/com/xsn/explorer/data/BlockDataHandler.scala

@@ -8,7 +8,7 @@ import scala.language.higherKinds
 
 trait BlockDataHandler[F[_]] {
 
-  def upsert(block: Block): F[Block]
+  def insert(block: Block): F[Block]
 
   def getBy(blockhash: Blockhash): F[Block]
 

server/app/com/xsn/explorer/data/anorm/BlockPostgresDataHandler.scala

@@ -5,7 +5,7 @@ import javax.inject.Inject
 import com.alexitc.playsonify.core.ApplicationResult
 import com.xsn.explorer.data.BlockBlockingDataHandler
 import com.xsn.explorer.data.anorm.dao.BlockPostgresDAO
-import com.xsn.explorer.errors.{BlockNotFoundError, BlockUnknownError}
+import com.xsn.explorer.errors._
 import com.xsn.explorer.models.Blockhash
 import com.xsn.explorer.models.rpc.Block
 import org.scalactic.{One, Or}
@@ -17,9 +17,19 @@ class BlockPostgresDataHandler @Inject() (
     extends BlockBlockingDataHandler
     with AnormPostgresDataHandler {
 
-  override def upsert(block: Block): ApplicationResult[Block] = database.withConnection { implicit conn =>
-    val maybe = blockPostgresDAO.upsert(block)
-    Or.from(maybe, One(BlockUnknownError))
+  override def insert(block: Block): ApplicationResult[Block] = {
+    val result = withConnection { implicit conn =>
+      val maybe = blockPostgresDAO.insert(block)
+      Or.from(maybe, One(BlockUnknownError))
+    }
+
+    result.badMap { errors =>
+      errors.map {
+        case PostgresForeignKeyViolationError("blockhash", _) => RepeatedBlockhashError
+        case PostgresForeignKeyViolationError("height", _) => RepeatedBlockHeightError
+        case e => e
+      }
+    }
   }
 
   override def getBy(blockhash: Blockhash): ApplicationResult[Block] = database.withConnection { implicit conn =>

server/app/com/xsn/explorer/data/anorm/DatabasePostgresSeeder.scala

@@ -11,6 +11,7 @@ import com.xsn.explorer.models.rpc.Block
 import com.xsn.explorer.models.{Address, Balance, Transaction}
 import com.xsn.explorer.util.Extensions.ListOptionExt
 import org.scalactic.Good
+import org.slf4j.LoggerFactory
 import play.api.db.Database
 
 class DatabasePostgresSeeder @Inject() (
@@ -21,6 +22,8 @@ class DatabasePostgresSeeder @Inject() (
     extends DatabaseBlockingSeeder
     with AnormPostgresDataHandler {
 
+  private val logger = LoggerFactory.getLogger(this.getClass)
+
   override def firstBlock(command: CreateBlockCommand): ApplicationResult[Unit] = database.withTransaction { implicit conn =>
     val result = upsertBlockCascade(command)
 
@@ -34,9 +37,13 @@ class DatabasePostgresSeeder @Inject() (
     val result = for {
       // link previous block
       previousBlockhash <- command.block.previousBlockhash
-      previous <- blockPostgresDAO.getBy(previousBlockhash)
-      newPrevious = previous.copy(nextBlockhash = Some(command.block.hash))
-      _ <- blockPostgresDAO.upsert(newPrevious)
+      _ <- blockPostgresDAO
+          .setNextBlockhash(previousBlockhash, command.block.hash)
+          .orElse {
+            logger.warn(s"Failed to link previous block = ${previousBlockhash.string} to ${command.block.hash.string} because it wasn't found")
+            None
+          }
+
       _ <- upsertBlockCascade(command)
     } yield ()
 
@@ -71,7 +78,10 @@ class DatabasePostgresSeeder @Inject() (
   private def upsertBlockCascade(command: CreateBlockCommand)(implicit conn: Connection): Option[Unit] = {
     for {
       // block
-      _ <- blockPostgresDAO.upsert(command.block)
+      _ <- blockPostgresDAO
+            .delete(command.block.hash)
+            .orElse { Some(command.block) }
+      _ <- blockPostgresDAO.insert(command.block)
 
       // transactions
       _ <- command.transactions.map(tx => transactionPostgresDAO.upsert(tx)).everything

server/app/com/xsn/explorer/data/anorm/dao/BlockPostgresDAO.scala

@@ -9,7 +9,7 @@ import com.xsn.explorer.models.rpc.Block
 
 class BlockPostgresDAO {
 
-  def upsert(block: Block)(implicit conn: Connection): Option[Block] = {
+  def insert(block: Block)(implicit conn: Connection): Option[Block] = {
     SQL(
       """
         |INSERT INTO blocks
@@ -22,21 +22,6 @@ class BlockPostgresDAO {
         |    {blockhash}, {previous_blockhash}, {next_blockhash}, {tpos_contract}, {merkle_root}, {size},
         |    {height}, {version}, {time}, {median_time}, {nonce}, {bits}, {chainwork}, {difficulty}
         |  )
-        |ON CONFLICT (blockhash)
-        |DO UPDATE
-        |  SET previous_blockhash = EXCLUDED.previous_blockhash,
-        |      next_blockhash = EXCLUDED.next_blockhash,
-        |      tpos_contract = EXCLUDED.tpos_contract,
-        |      merkle_root = EXCLUDED.merkle_root,
-        |      size = EXCLUDED.size,
-        |      height = EXCLUDED.height,
-        |      version = EXCLUDED.version,
-        |      time = EXCLUDED.time,
-        |      median_time = EXCLUDED.median_time,
-        |      nonce = EXCLUDED.nonce,
-        |      bits = EXCLUDED.bits,
-        |      chainwork = EXCLUDED.chainwork,
-        |      difficulty = EXCLUDED.difficulty
         |RETURNING blockhash, previous_blockhash, next_blockhash, tpos_contract, merkle_root, size,
         |          height, version, time, median_time, nonce, bits, chainwork, difficulty
       """.stripMargin
@@ -55,6 +40,25 @@ class BlockPostgresDAO {
       'bits -> block.bits,
       'chainwork -> block.chainwork,
       'difficulty -> block.difficulty
+    ).as(parseBlock.single)
+  }
+
+  def setNextBlockhash(
+      blockhash: Blockhash,
+      nextBlockhash: Blockhash)(
+      implicit conn: Connection): Option[Block] = {
+
+    SQL(
+      """
+        |UPDATE blocks
+        |SET next_blockhash = {next_blockhash}
+        |WHERE blockhash = {blockhash}
+        |RETURNING blockhash, previous_blockhash, next_blockhash, tpos_contract, merkle_root, size,
+        |          height, version, time, median_time, nonce, bits, chainwork, difficulty
+      """.stripMargin
+    ).on(
+      'blockhash -> blockhash.string,
+      'next_blockhash -> nextBlockhash.string
     ).as(parseBlock.singleOpt).flatten
   }
 

server/app/com/xsn/explorer/data/async/BlockFutureDataHandler.scala

@@ -15,8 +15,8 @@ class BlockFutureDataHandler @Inject() (
     implicit ec: DatabaseExecutionContext)
     extends BlockDataHandler[FutureApplicationResult] {
 
-  def upsert(block: Block): FutureApplicationResult[Block] = Future {
-    blockBlockingDataHandler.upsert(block)
+  def insert(block: Block): FutureApplicationResult[Block] = Future {
+    blockBlockingDataHandler.insert(block)
   }
 
   def getBy(blockhash: Blockhash): FutureApplicationResult[Block] = Future {

server/app/com/xsn/explorer/errors/blockErrors.scala

@@ -27,3 +27,13 @@ case object BlockUnknownError extends BlockError with ServerError {
   override def cause: Option[Throwable] = None
   override def toPublicErrorList(messagesApi: MessagesApi)(implicit lang: Lang): List[PublicError] = List.empty
 }
+
+case object RepeatedBlockhashError extends BlockError with ServerError {
+  override def cause: Option[Throwable] = None
+  override def toPublicErrorList(messagesApi: MessagesApi)(implicit lang: Lang): List[PublicError] = List.empty
+}
+
+case object RepeatedBlockHeightError extends BlockError with ServerError {
+  override def cause: Option[Throwable] = None
+  override def toPublicErrorList(messagesApi: MessagesApi)(implicit lang: Lang): List[PublicError] = List.empty
+}

server/conf/evolutions/default/4.sql

@@ -0,0 +1,14 @@
+
+# --- !Ups
+
+DROP INDEX blocks_height_index;
+
+ALTER TABLE blocks
+ADD CONSTRAINT blocks_height_unique UNIQUE (height);
+
+# --- !Downs
+
+ALTER TABLE blocks
+DROP CONSTRAINT blocks_height_unique;
+
+CREATE INDEX blocks_height_index ON blocks USING BTREE (height);

server/test/com/xsn/explorer/data/BlockPostgresDataHandlerSpec.scala

@@ -3,35 +3,49 @@ package com.xsn.explorer.data
 import com.xsn.explorer.data.anorm.BlockPostgresDataHandler
 import com.xsn.explorer.data.anorm.dao.BlockPostgresDAO
 import com.xsn.explorer.data.common.PostgresDataHandlerSpec
-import com.xsn.explorer.errors.BlockNotFoundError
+import com.xsn.explorer.errors.{BlockNotFoundError, RepeatedBlockHeightError, RepeatedBlockhashError}
 import com.xsn.explorer.helpers.BlockLoader
 import com.xsn.explorer.models.Blockhash
 import com.xsn.explorer.models.rpc.Block
 import org.scalactic.Bad
+import org.scalatest.BeforeAndAfter
 
-class BlockPostgresDataHandlerSpec extends PostgresDataHandlerSpec {
+class BlockPostgresDataHandlerSpec extends PostgresDataHandlerSpec with BeforeAndAfter {
+
+  before {
+    clearDatabase()
+  }
 
   lazy val dataHandler = new BlockPostgresDataHandler(database, new BlockPostgresDAO)
 
-  "upsert" should {
+  "insert" should {
     "add a new block" in {
       // PoS block
       val block = BlockLoader.get("1ca318b7a26ed67ca7c8c9b5069d653ba224bf86989125d1dfbb0973b7d6a5e0")
 
-      val result = dataHandler.upsert(block)
+      val result = dataHandler.insert(block)
       result.isGood mustEqual true
       matches(block, result.get)
     }
 
-    "override an existing block" in {
+    "fail on existing blockhash" in {
       val block = BlockLoader.get("1ca318b7a26ed67ca7c8c9b5069d653ba224bf86989125d1dfbb0973b7d6a5e0")
-      dataHandler.upsert(block)
+      dataHandler.insert(block).isGood mustEqual true
 
-      val newBlock = BlockLoader.get("25762bf01143f7fe34912c926e0b95528b082c6323de35516de0fc321f5d8058").copy(hash = block.hash)
-      val expected = newBlock.copy(hash = block.hash)
-      val result = dataHandler.upsert(newBlock)
-      result.isGood mustEqual true
-      matches(expected, result.get)
+      val newBlock = BlockLoader.get("25762bf01143f7fe34912c926e0b95528b082c6323de35516de0fc321f5d8058")
+          .copy(hash = block.hash)
+      val result = dataHandler.insert(newBlock)
+      result mustEqual Bad(RepeatedBlockhashError).accumulating
+    }
+
+    "fail on existing height" in {
+      val block = BlockLoader.get("1ca318b7a26ed67ca7c8c9b5069d653ba224bf86989125d1dfbb0973b7d6a5e0")
+      dataHandler.insert(block).isGood mustEqual true
+
+      val newBlock = BlockLoader.get("25762bf01143f7fe34912c926e0b95528b082c6323de35516de0fc321f5d8058")
+          .copy(height = block.height)
+      val result = dataHandler.insert(newBlock)
+      result mustEqual Bad(RepeatedBlockHeightError).accumulating
     }
   }
 
@@ -39,7 +53,7 @@ class BlockPostgresDataHandlerSpec extends PostgresDataHandlerSpec {
     "return a block" in {
       val block = BlockLoader.get("1ca318b7a26ed67ca7c8c9b5069d653ba224bf86989125d1dfbb0973b7d6a5e0")
 
-      dataHandler.upsert(block)
+      dataHandler.insert(block)
 
       val result = dataHandler.getBy(block.hash)
       result.isGood mustEqual true
@@ -57,7 +71,7 @@ class BlockPostgresDataHandlerSpec extends PostgresDataHandlerSpec {
   "delete" should {
     "delete a block" in {
       val block = BlockLoader.get("1ca318b7a26ed67ca7c8c9b5069d653ba224bf86989125d1dfbb0973b7d6a5e0")
-      dataHandler.upsert(block)
+      dataHandler.insert(block)
 
       val result = dataHandler.delete(block.hash)
       result.isGood mustEqual true
@@ -80,7 +94,7 @@ class BlockPostgresDataHandlerSpec extends PostgresDataHandlerSpec {
       val block1 = BlockLoader.get("000003fb382f6892ae96594b81aa916a8923c70701de4e7054aac556c7271ef7")
       val block2 = BlockLoader.get("000004645e2717b556682e3c642a4c6e473bf25c653ff8e8c114a3006040ffb8")
 
-      List(block1, block2, block0).foreach(dataHandler.upsert)
+      List(block1, block2, block0).foreach(dataHandler.insert)
 
       val result = dataHandler.getLatestBlock()
       result.isGood mustEqual true
@@ -103,7 +117,7 @@ class BlockPostgresDataHandlerSpec extends PostgresDataHandlerSpec {
       val block1 = BlockLoader.get("000003fb382f6892ae96594b81aa916a8923c70701de4e7054aac556c7271ef7")
       val block2 = BlockLoader.get("000004645e2717b556682e3c642a4c6e473bf25c653ff8e8c114a3006040ffb8")
 
-      List(block1, block2, block0).map(dataHandler.upsert).foreach(_.isGood mustEqual true)
+      List(block1, block2, block0).map(dataHandler.insert).foreach(_.isGood mustEqual true)
 
       val result = dataHandler.getFirstBlock()
       result.isGood mustEqual true

server/test/com/xsn/explorer/processors/BlockEventsProcessorSpec.scala

@@ -1,18 +1,25 @@
 package com.xsn.explorer.processors
 
+import com.alexitc.playsonify.core.FutureApplicationResult
 import com.xsn.explorer.data.anorm.dao.{BalancePostgresDAO, BlockPostgresDAO, StatisticsPostgresDAO, TransactionPostgresDAO}
 import com.xsn.explorer.data.anorm.interpreters.FieldOrderingSQLInterpreter
 import com.xsn.explorer.data.anorm.{BalancePostgresDataHandler, BlockPostgresDataHandler, DatabasePostgresSeeder, StatisticsPostgresDataHandler}
 import com.xsn.explorer.data.async.{BlockFutureDataHandler, DatabaseFutureSeeder}
 import com.xsn.explorer.data.common.PostgresDataHandlerSpec
+import com.xsn.explorer.errors.{BlockNotFoundError, TransactionNotFoundError}
 import com.xsn.explorer.helpers.{BlockLoader, Executors, FileBasedXSNService}
 import com.xsn.explorer.models.base._
 import com.xsn.explorer.models.fields.BalanceField
-import com.xsn.explorer.models.rpc.Block
+import com.xsn.explorer.models.rpc.{Block, Transaction}
+import com.xsn.explorer.models.{Blockhash, TransactionId}
+import com.xsn.explorer.processors.BlockEventsProcessor.{NewBlockAppended, RechainDone}
 import com.xsn.explorer.services.TransactionService
+import org.scalactic.{Bad, Good}
 import org.scalatest.BeforeAndAfter
 import org.scalatest.concurrent.ScalaFutures
 
+import scala.concurrent.Future
+
 class BlockEventsProcessorSpec extends PostgresDataHandlerSpec with ScalaFutures with BeforeAndAfter {
 
   lazy val dataHandler = new BlockPostgresDataHandler(database, new BlockPostgresDAO)
@@ -56,10 +63,10 @@ class BlockEventsProcessorSpec extends PostgresDataHandlerSpec with ScalaFutures
       val block2 = BlockLoader.get("000004645e2717b556682e3c642a4c6e473bf25c653ff8e8c114a3006040ffb8")
       val block3 = BlockLoader.get("00000766115b26ecbc09cd3a3db6870fdaf2f049d65a910eb2f2b48b566ca7bd")
 
-      List(block1, block2).map(dataHandler.upsert).foreach(_.isGood mustEqual true)
+      List(block1, block2).map(dataHandler.insert).foreach(_.isGood mustEqual true)
 
       whenReady(processor.newLatestBlock(block3.hash)) { result =>
-        result.isGood mustEqual true
+        result mustEqual Good(NewBlockAppended(block3))
         val blocks = List(block1, block2, block3)
         verifyBlockchain(blocks)
       }
@@ -70,12 +77,17 @@ class BlockEventsProcessorSpec extends PostgresDataHandlerSpec with ScalaFutures
       val block2 = BlockLoader.get("000004645e2717b556682e3c642a4c6e473bf25c653ff8e8c114a3006040ffb8")
       val block3 = BlockLoader.get("00000766115b26ecbc09cd3a3db6870fdaf2f049d65a910eb2f2b48b566ca7bd")
 
-      List(block1, block2, block3).map(dataHandler.upsert).foreach(_.isGood mustEqual true)
+      List(block1, block2, block3).map(dataHandler.insert).foreach(_.isGood mustEqual true)
 
-      whenReady(processor.newLatestBlock(block2.hash)) { result =>
-        result.isGood mustEqual true
-        val blocks = List(block1, block2)
-        verifyBlockchain(blocks)
+      whenReady(processor.newLatestBlock(block2.hash)) {
+        case Good(RechainDone(orphanBlock, newBlock)) =>
+          orphanBlock.hash mustEqual block3.hash
+          newBlock.hash mustEqual block2.hash
+
+          val blocks = List(block1, block2)
+          verifyBlockchain(blocks)
+
+        case _ => fail()
       }
     }
 
@@ -84,7 +96,7 @@ class BlockEventsProcessorSpec extends PostgresDataHandlerSpec with ScalaFutures
       val block2 = BlockLoader.get("000004645e2717b556682e3c642a4c6e473bf25c653ff8e8c114a3006040ffb8")
       val block3 = BlockLoader.get("00000766115b26ecbc09cd3a3db6870fdaf2f049d65a910eb2f2b48b566ca7bd")
 
-      List(block2, block3).map(dataHandler.upsert).foreach(_.isGood mustEqual true)
+      List(block2, block3).map(dataHandler.insert).foreach(_.isGood mustEqual true)
 
       whenReady(processor.newLatestBlock(block1.hash)) { result =>
         result.isGood mustEqual true
@@ -98,7 +110,7 @@ class BlockEventsProcessorSpec extends PostgresDataHandlerSpec with ScalaFutures
       val block2 = BlockLoader.get("000004645e2717b556682e3c642a4c6e473bf25c653ff8e8c114a3006040ffb8")
       val block3 = BlockLoader.get("00000766115b26ecbc09cd3a3db6870fdaf2f049d65a910eb2f2b48b566ca7bd")
 
-      List(block1, block2, block3).map(dataHandler.upsert).foreach(_.isGood mustEqual true)
+      List(block1, block2, block3).map(dataHandler.insert).foreach(_.isGood mustEqual true)
 
       whenReady(processor.newLatestBlock(block1.hash)) { result =>
         result.isGood mustEqual true