Created SlickQueryBuilder

3 files changed, 446 insertions, 1 deletions

diff --git a/build.sbt b/build.sbt
index 8801de7..7778e02 100644
--- a/build.sbt
+++ b/build.sbt
@@ -28,5 +28,6 @@ lazy val core = (project in file("."))
     "org.asynchttpclient"               % "async-http-client"       % "2.0.24",
     "org.slf4j"                         % "slf4j-api"               % "1.7.21",
     "ai.x"                              %% "diff"                   % "1.2.0-get-simple-name-fix" % "test",
-    "org.scalatest"                     %% "scalatest"              % "3.0.0" % "test"
+    "org.scalatest"                     %% "scalatest"              % "3.0.0" % "test",
+    "xyz.driver"                        %% "core"                   % "0.16.3" excludeAll (ExclusionRule(organization = "io.netty"))
   ))
diff --git a/src/main/scala/xyz/driver/pdsuicommon/db/SlickPostgresQueryBuilder.scala b/src/main/scala/xyz/driver/pdsuicommon/db/SlickPostgresQueryBuilder.scala
new file mode 100644
index 0000000..66434f0
--- /dev/null
+++ b/src/main/scala/xyz/driver/pdsuicommon/db/SlickPostgresQueryBuilder.scala
@@ -0,0 +1,103 @@
+package xyz.driver.pdsuicommon.db
+
+import java.time.{LocalDateTime, ZoneOffset}
+
+import slick.driver.JdbcProfile
+import slick.jdbc.GetResult
+import xyz.driver.core.database.SlickDal
+
+import scala.collection.breakOut
+import scala.concurrent.ExecutionContext
+
+object SlickPostgresQueryBuilder {
+
+  import xyz.driver.pdsuicommon.db.SlickQueryBuilder._
+
+  def apply[T](tableName: String,
+               lastUpdateFieldName: Option[String],
+               nullableFields: Set[String],
+               links: Set[SlickTableLink],
+               runner: Runner[T],
+               countRunner: CountRunner)(implicit sqlContext: SlickDal,
+                                         profile: JdbcProfile,
+                                         getResult: GetResult[T],
+                                         ec: ExecutionContext): SlickPostgresQueryBuilder[T] = {
+    val parameters = SlickPostgresQueryBuilderParameters(
+      tableData = TableData(tableName, lastUpdateFieldName, nullableFields),
+      links = links.map(x => x.foreignTableName -> x)(breakOut)
+    )
+    new SlickPostgresQueryBuilder[T](parameters)(runner, countRunner)
+  }
+
+  def apply[T](tableName: String,
+               lastUpdateFieldName: Option[String],
+               nullableFields: Set[String],
+               links: Set[SlickTableLink])(implicit sqlContext: SlickDal,
+                                           profile: JdbcProfile,
+                                           getResult: GetResult[T],
+                                           ec: ExecutionContext): SlickPostgresQueryBuilder[T] = {
+    apply(tableName, SlickQueryBuilderParameters.AllFields, lastUpdateFieldName, nullableFields, links)
+  }
+
+  def apply[T](tableName: String,
+               fields: Set[String],
+               lastUpdateFieldName: Option[String],
+               nullableFields: Set[String],
+               links: Set[SlickTableLink])(implicit sqlContext: SlickDal,
+                                           profile: JdbcProfile,
+                                           getResult: GetResult[T],
+                                           ec: ExecutionContext): SlickPostgresQueryBuilder[T] = {
+
+    val runner: Runner[T] = { parameters =>
+      val sql = parameters.toSql(countQuery = false, fields = fields).as[T]
+      sqlContext.execute(sql)
+    }
+
+    val countRunner: CountRunner = { parameters =>
+      implicit val getCountResult: GetResult[(Int, Option[LocalDateTime])] = GetResult({ r =>
+        val count = r.rs.getInt(1)
+        val lastUpdate = if (parameters.tableData.lastUpdateFieldName.isDefined) {
+          Option(r.rs.getTimestamp(2)).map(timestampToLocalDateTime)
+        } else None
+        (count, lastUpdate)
+      })
+      val sql = parameters.toSql(countQuery = true).as[(Int, Option[LocalDateTime])]
+      sqlContext.execute(sql).map(_.head)
+    }
+
+    apply[T](
+      tableName = tableName,
+      lastUpdateFieldName = lastUpdateFieldName,
+      nullableFields = nullableFields,
+      links = links,
+      runner = runner,
+      countRunner = countRunner
+    )
+  }
+
+  def timestampToLocalDateTime(timestamp: java.sql.Timestamp): LocalDateTime = {
+    LocalDateTime.ofInstant(timestamp.toInstant, ZoneOffset.UTC)
+  }
+}
+
+class SlickPostgresQueryBuilder[T](parameters: SlickPostgresQueryBuilderParameters)(
+        implicit runner: SlickQueryBuilder.Runner[T],
+        countRunner: SlickQueryBuilder.CountRunner)
+    extends SlickQueryBuilder[T](parameters) {
+
+  def withFilter(newFilter: SearchFilterExpr): SlickQueryBuilder[T] = {
+    new SlickPostgresQueryBuilder[T](parameters.copy(filter = newFilter))
+  }
+
+  def withSorting(newSorting: Sorting): SlickQueryBuilder[T] = {
+    new SlickPostgresQueryBuilder[T](parameters.copy(sorting = newSorting))
+  }
+
+  def withPagination(newPagination: Pagination): SlickQueryBuilder[T] = {
+    new SlickPostgresQueryBuilder[T](parameters.copy(pagination = Some(newPagination)))
+  }
+
+  def resetPagination: SlickQueryBuilder[T] = {
+    new SlickPostgresQueryBuilder[T](parameters.copy(pagination = None))
+  }
+}
diff --git a/src/main/scala/xyz/driver/pdsuicommon/db/SlickQueryBuilder.scala b/src/main/scala/xyz/driver/pdsuicommon/db/SlickQueryBuilder.scala
new file mode 100644
index 0000000..e45ff87
--- /dev/null
+++ b/src/main/scala/xyz/driver/pdsuicommon/db/SlickQueryBuilder.scala
@@ -0,0 +1,341 @@
+package xyz.driver.pdsuicommon.db
+
+import java.sql.PreparedStatement
+import java.time.LocalDateTime
+
+import slick.driver.JdbcProfile
+import slick.jdbc.{PositionedParameters, SQLActionBuilder, SetParameter}
+import xyz.driver.pdsuicommon.db.Sorting.{Dimension, Sequential}
+import xyz.driver.pdsuicommon.db.SortingOrder.{Ascending, Descending}
+
+import scala.concurrent.{ExecutionContext, Future}
+
+object SlickQueryBuilder {
+
+  type Runner[T] = SlickQueryBuilderParameters => Future[Seq[T]]
+
+  type CountResult = Future[(Int, Option[LocalDateTime])]
+
+  type CountRunner = SlickQueryBuilderParameters => CountResult
+
+  /**
+    * Binder for PreparedStatement
+    */
+  type Binder = PreparedStatement => PreparedStatement
+
+  final case class TableData(tableName: String,
+                             lastUpdateFieldName: Option[String] = None,
+                             nullableFields: Set[String] = Set.empty)
+
+  val AllFields = Set("*")
+
+  implicit class SQLActionBuilderConcat(a: SQLActionBuilder) {
+    def concat(b: SQLActionBuilder): SQLActionBuilder = {
+      SQLActionBuilder(a.queryParts ++ b.queryParts, new SetParameter[Unit] {
+        def apply(p: Unit, pp: PositionedParameters): Unit = {
+          a.unitPConv.apply(p, pp)
+          b.unitPConv.apply(p, pp)
+        }
+      })
+    }
+  }
+}
+
+final case class SlickTableLink(keyColumnName: String, foreignTableName: String, foreignKeyColumnName: String)
+
+object SlickQueryBuilderParameters {
+  val AllFields = Set("*")
+}
+
+sealed trait SlickQueryBuilderParameters {
+  import SlickQueryBuilder._
+
+  def tableData: SlickQueryBuilder.TableData
+  def links: Map[String, SlickTableLink]
+  def filter: SearchFilterExpr
+  def sorting: Sorting
+  def pagination: Option[Pagination]
+
+  def findLink(tableName: String): SlickTableLink = links.get(tableName) match {
+    case None       => throw new IllegalArgumentException(s"Cannot find a link for `$tableName`")
+    case Some(link) => link
+  }
+
+  def toSql(countQuery: Boolean = false)(implicit profile: JdbcProfile): SQLActionBuilder = {
+    toSql(countQuery, QueryBuilderParameters.AllFields)
+  }
+
+  def toSql(countQuery: Boolean, fields: Set[String])(implicit profile: JdbcProfile): SQLActionBuilder = {
+    import profile.api._
+    val escapedTableName = tableData.tableName
+    val fieldsSql: String = if (countQuery) {
+      val suffix: String = tableData.lastUpdateFieldName match {
+        case Some(lastUpdateField) => s", max($escapedTableName.$lastUpdateField)"
+        case None                  => ""
+      }
+      "count(*)" + suffix
+    } else {
+      if (fields == SlickQueryBuilderParameters.AllFields) {
+        s"$escapedTableName.*"
+      } else {
+        fields
+          .map { field =>
+            s"$escapedTableName.$field"
+          }
+          .mkString(", ")
+      }
+    }
+    val where   = filterToSql(escapedTableName, filter)
+    val orderBy = sortingToSql(escapedTableName, sorting)
+
+    val limitSql = limitToSql()
+
+    val sql = sql"select #$fieldsSql from #$escapedTableName"
+
+    val filtersTableLinks: Seq[SlickTableLink] = {
+      import SearchFilterExpr._
+      def aux(expr: SearchFilterExpr): Seq[SlickTableLink] = expr match {
+        case Atom.TableName(tableName) => List(findLink(tableName))
+        case Intersection(xs)          => xs.flatMap(aux)
+        case Union(xs)                 => xs.flatMap(aux)
+        case _                         => Nil
+      }
+      aux(filter)
+    }
+
+    val sortingTableLinks: Seq[SlickTableLink] = Sorting.collect(sorting) {
+      case Dimension(Some(foreignTableName), _, _) => findLink(foreignTableName)
+    }
+
+    // Combine links from sorting and filter without duplicates
+    val foreignTableLinks = (filtersTableLinks ++ sortingTableLinks).distinct
+
+    foreignTableLinks.foreach {
+      case SlickTableLink(keyColumnName, foreignTableName, foreignKeyColumnName) =>
+        sql = sql concat sql"""inner join #$foreignTableName
+             on #$escapedTableName.#$keyColumnName = #$foreignTableName.#$foreignKeyColumnName"""
+    }
+
+    if (where.toString.nonEmpty) {
+      sql = sql concat sql"where #$where"
+    }
+
+    if (orderBy.toString.nonEmpty && !countQuery) {
+      sql = sql concat sql"order by #$orderBy"
+    }
+
+    if (limitSql.toString.nonEmpty && !countQuery) {
+      sql = sql concat sql"#$limitSql"
+    }
+
+    sql
+  }
+
+  /**
+    * Converts filter expression to SQL expression.
+    *
+    * @return Returns SQL string and list of values for binding in prepared statement.
+    */
+  protected def filterToSql(escapedTableName: String, filter: SearchFilterExpr)(
+          implicit profile: JdbcProfile): SQLActionBuilder = {
+    import SearchFilterBinaryOperation._
+    import SearchFilterExpr._
+    import profile.api._
+
+    def isNull(string: AnyRef) = Option(string).isEmpty || string.toString.toLowerCase == "null"
+
+    def escapeDimension(dimension: SearchFilterExpr.Dimension) = {
+      val tableName = escapedTableName
+      s"$tableName.$dimension.name"
+    }
+
+    def filterToSqlMultiple(operands: Seq[SearchFilterExpr]) = operands.collect {
+      case x if !SearchFilterExpr.isEmpty(x) => filterToSql(escapedTableName, x)
+    }
+
+    def multipleSqlToAction(op: String, conditions: Seq[SQLActionBuilder]): SQLActionBuilder = {
+      var first     = true
+      var filterSql = sql"("
+      for (condition <- conditions) {
+        if (first) {
+          filterSql = filterSql concat condition
+          first = false
+        } else {
+          filterSql = filterSql concat sql" #$op " concat condition
+        }
+      }
+      filterSql concat sql")"
+    }
+
+    filter match {
+      case x if isEmpty(x) =>
+        sql""
+
+      case AllowAll =>
+        sql"1"
+
+      case DenyAll =>
+        sql"0"
+
+      case Atom.Binary(dimension, Eq, value) if isNull(value) =>
+        sql"#${escapeDimension(dimension)} is NULL"
+
+      case Atom.Binary(dimension, NotEq, value) if isNull(value) =>
+        sql"#${escapeDimension(dimension)} is not NULL"
+
+      case Atom.Binary(dimension, NotEq, value) if tableData.nullableFields.contains(dimension.name) =>
+        // In MySQL NULL <> Any === NULL
+        // So, to handle NotEq for nullable fields we need to use more complex SQL expression.
+        // http://dev.mysql.com/doc/refman/5.7/en/working-with-null.html
+        val escapedColumn = escapeDimension(dimension)
+        sql"(#$escapedColumn is null or #$escapedColumn != #$value)"
+
+      case Atom.Binary(dimension, op, value) =>
+        val operator = op match {
+          case Eq    => sql"="
+          case NotEq => sql"!="
+          case Like  => sql"like"
+          case Gt    => sql">"
+          case GtEq  => sql">="
+          case Lt    => sql"<"
+          case LtEq  => sql"<="
+        }
+        sql"#${escapeDimension(dimension)}" concat operator concat sql"#$value"
+
+      case Atom.NAry(dimension, op, values) =>
+        val sqlOp = op match {
+          case SearchFilterNAryOperation.In    => sql"in"
+          case SearchFilterNAryOperation.NotIn => sql"not in"
+        }
+
+        val formattedValues = if (values.nonEmpty) {
+          sql"#$values"
+        } else sql"NULL"
+        sql"#${escapeDimension(dimension)}" concat sqlOp concat formattedValues
+
+      case Intersection(operands) =>
+        multipleSqlToAction("and", filterToSqlMultiple(operands))
+
+      case Union(operands) =>
+        multipleSqlToAction("or", filterToSqlMultiple(operands))
+    }
+  }
+
+  protected def limitToSql()(implicit profile: JdbcProfile): SQLActionBuilder
+
+  /**
+    * @param escapedMainTableName Should be escaped
+    */
+  protected def sortingToSql(escapedMainTableName: String, sorting: Sorting)(
+          implicit profile: JdbcProfile): SQLActionBuilder = {
+    import profile.api._
+    sorting match {
+      case Dimension(optSortingTableName, field, order) =>
+        val sortingTableName = optSortingTableName.getOrElse(escapedMainTableName)
+        val fullName         = s"$sortingTableName.$field"
+
+        sql"#$fullName #${orderToSql(order)}"
+
+      case Sequential(xs) =>
+        sql"#${xs.map(sortingToSql(escapedMainTableName, _)).mkString(", ")}"
+    }
+  }
+
+  protected def orderToSql(x: SortingOrder): String = x match {
+    case Ascending  => "asc"
+    case Descending => "desc"
+  }
+
+  protected def binder(bindings: List[AnyRef])(bind: PreparedStatement): PreparedStatement = {
+    bindings.zipWithIndex.foreach {
+      case (binding, index) =>
+        bind.setObject(index + 1, binding)
+    }
+
+    bind
+  }
+
+}
+
+final case class SlickPostgresQueryBuilderParameters(tableData: SlickQueryBuilder.TableData,
+                                                     links: Map[String, SlickTableLink] = Map.empty,
+                                                     filter: SearchFilterExpr = SearchFilterExpr.Empty,
+                                                     sorting: Sorting = Sorting.Empty,
+                                                     pagination: Option[Pagination] = None)
+    extends SlickQueryBuilderParameters {
+
+  def limitToSql()(implicit profile: JdbcProfile): SQLActionBuilder = {
+    import profile.api._
+    pagination.map { pagination =>
+      val startFrom = (pagination.pageNumber - 1) * pagination.pageSize
+      sql"limit #${pagination.pageSize} OFFSET #$startFrom"
+    } getOrElse (sql"")
+  }
+
+}
+
+/**
+  * @param links Links to another tables grouped by foreignTableName
+  */
+final case class SlickMysqlQueryBuilderParameters(tableData: SlickQueryBuilder.TableData,
+                                                  links: Map[String, SlickTableLink] = Map.empty,
+                                                  filter: SearchFilterExpr = SearchFilterExpr.Empty,
+                                                  sorting: Sorting = Sorting.Empty,
+                                                  pagination: Option[Pagination] = None)
+    extends SlickQueryBuilderParameters {
+
+  def limitToSql()(implicit profile: JdbcProfile): SQLActionBuilder = {
+    import profile.api._
+    pagination
+      .map { pagination =>
+        val startFrom = (pagination.pageNumber - 1) * pagination.pageSize
+        sql"limit #$startFrom, #${pagination.pageSize}"
+      }
+      .getOrElse(sql"")
+  }
+
+}
+
+abstract class SlickQueryBuilder[T](val parameters: SlickQueryBuilderParameters)(
+        implicit runner: SlickQueryBuilder.Runner[T],
+        countRunner: SlickQueryBuilder.CountRunner) {
+
+  def run()(implicit ec: ExecutionContext): Future[Seq[T]] = runner(parameters)
+
+  def runCount()(implicit ec: ExecutionContext): SlickQueryBuilder.CountResult = countRunner(parameters)
+
+  /**
+    * Runs the query and returns total found rows without considering of pagination.
+    */
+  def runWithCount()(implicit ec: ExecutionContext): Future[(Seq[T], Int, Option[LocalDateTime])] = {
+    for {
+      all                 <- run
+      (total, lastUpdate) <- runCount
+    } yield (all, total, lastUpdate)
+  }
+
+  def withFilter(newFilter: SearchFilterExpr): SlickQueryBuilder[T]
+
+  def withFilter(filter: Option[SearchFilterExpr]): SlickQueryBuilder[T] = {
+    filter.fold(this)(withFilter)
+  }
+
+  def resetFilter: SlickQueryBuilder[T] = withFilter(SearchFilterExpr.Empty)
+
+  def withSorting(newSorting: Sorting): SlickQueryBuilder[T]
+
+  def withSorting(sorting: Option[Sorting]): SlickQueryBuilder[T] = {
+    sorting.fold(this)(withSorting)
+  }
+
+  def resetSorting: SlickQueryBuilder[T] = withSorting(Sorting.Empty)
+
+  def withPagination(newPagination: Pagination): SlickQueryBuilder[T]
+
+  def withPagination(pagination: Option[Pagination]): SlickQueryBuilder[T] = {
+    pagination.fold(this)(withPagination)
+  }
+
+  def resetPagination: SlickQueryBuilder[T]
+
+}