gitbucket / blocking-slick   0.0.14

Apache License 2.0 GitHub

Slick2 compatible blocking API for Slick3

Scala versions: 3.x 2.13 2.12

blocking-slick Scala CI

Provides Slick2 compatible blocking API for Slick3.

Setup

Add following dependency to your build.sbt:

// for Slick 3.5 (Scala 2 / Scala 3)
libraryDependencies += "com.github.takezoe" %% "blocking-slick" % "0.0.15-RC2"

// for Slick 3.4 (Scala 2)
libraryDependencies += "com.github.takezoe" %% "blocking-slick" % "0.0.14"

// for Slick 3.3
libraryDependencies += "com.github.takezoe" %% "blocking-slick-33" % "0.0.13"

// for Slick 3.2
libraryDependencies += "com.github.takezoe" %% "blocking-slick-32" % "0.0.11"

// for Slick 3.1
libraryDependencies += "com.github.takezoe" %% "blocking-slick-31" % "0.0.7"

You can enable blocking API by import the blocking driver as follows:

import com.github.takezoe.slick.blocking.BlockingH2Driver.blockingApi._

Slick2 style blocking API

See the example of use of blocking API provided by blocking-slick:

val db = Database.forURL("jdbc:h2:mem:test")

db.withSession { implicit session =>
  // Create tables
  models.Tables.schema.create

  // Insert
  Users.insert(UsersRow(1, "takezoe"))
  
  // Insert returning new id
  val newID: Long = (Users returning Users.map(_.id)).insert(UsersRow(1, "takezoe"))

  // Select
  val users: Seq[UserRow] = Users.list
  
  // Select single record
  val user: UserRow = Users.filter(_.id === "takezoe".bind).first
  
  // Select single record with Option
  val user: Option[UserRow] = Users.filter(_.id === "takezoe".bind).firstOption

  // Update
  Users.filter(t => t.id === 1.bind).update(UsersRow(1, "naoki"))
  
  // Delete
  Users.filter(t => t.id === 1.bind).delete
  
  // Drop tables
  models.Tables.schema.remove
}

Plain sql can be executed synchronously as well.

val id = 1
val name = "takezoe"
val insert = sqlu"INSERT INTO USERS (ID, NAME) VALUES (${id1}, ${name1})"
insert.execute

Transaction is available by using withTransaction instead of withSession:

// Transaction
db.withTransaction { implicit session =>
  ...
}

DBIO support

blocking-slick also provides a way to run DBIO synchronously. It would help to rewrite Slick2 style code to Slick3 style code gradually.

db.withSession { implicit session =>
  val id1 = 1
  val id2 = 2
  val name1 = "takezoe"
  val name2 = "chibochibo"
  val insert1 = sqlu"INSERT INTO USERS (ID, NAME) VALUES (${id1}, ${name1})" andThen
                sqlu"INSERT INTO USERS (ID, NAME) VALUES (${id2}, ${name2})"
  insert1.run

  val query = for {
    count <- sql"SELECT COUNT(*) FROM USERS".as[Int].head
    max   <- sql"SELECT MAX(ID) FROM USERS".as[Int].head
  } yield (count, max)
  val (count1, max1) = query.run
  assert(count1 == 2)
  assert(max1 == 2)
}

Note that using flatMap and andThen requires an ExecutionContext, but if you run that code synchronously that value will be ignored.

Resources

You can see actual codes in the testcase, and also a blocking-slick with Play2 and play-slick example is available at here.