binders-cassandra
This is a data binder library for Cassandra written in Scala. Please see more information at binders library page
Cassandra data using DataStax Java Driver for Cassandra.
Example
Here is the sample of Scala class that is initialized with Cassandra session and allows you to do select/insert of some user data.
class Db(session: com.datastax.driver.core.Session) {
import ExecutionContext.Implicits.global
implicit val cache = new SessionQueryCache[PlainConverter](session)
// class for binding input/output parameters
case class User(userId: Int, name: String)
def insertUser(user: User): Future[Unit] = cql"insert into users(userid, name) values (?, ?)".bind(user).execute()
// returns Future[Iterator[User]]
def selectAllUsers: Future[Iterator[User]] = cql"select * from users".all[User]
// if no user is found will throw NoRowsSelectedException
def selectUser(userId: Int) = cql"select * from users where userId = $userId".one[User]
// if no user is found will return None, otherwise Some(User)
def selectUserIfFound(userId: Int) = cql"select * from users where userId = $userId".oneOption[User]
}
And this class could be used like this:
val cluster = Cluster.builder().addContactPoint("127.0.0.1").build()
val session = cluster.connect("binder_test")
val db = new Db(session)
Await.result(db.insertUser(db.User(9, "John")), 10 seconds)
val users = Await.result(db.selectAllUsers, 10 seconds)
println(users.toList)
For the unit tests and sample application working local instance of Cassandra is required. Please see also sample project inside samples/ folder and schema in db/dbscript.cql
SBT
To use library, add this line to the build.sbt file:
libraryDependencies += "eu.inn" %% "binders-cassandra" % "0.2.5"
Requirements
Currently tested and works with:
- binders-core 0.2.4
- Cassandra 2.0.1 (corresponding driver with prepared statements)
- Scala 2.11.2, 2.10.4
- sbt 0.13
- guava from google 16.0.1
License
Product licensed under BSD 3-clause as stated in file LICENSE
