GatlingCql

Gatling DSL support for Apache Cassandra CQL. Can be used with Scylla as well

Features

Basic Gatling DSL for Apache Cassandra CQL, prepared statements are supported as well.

import com.datastax.oss.driver.api.core.{ConsistencyLevel, CqlSession}
import io.gatling.core.Predef._
import io.gatling.core.scenario.Simulation
import io.github.gatling.cql.Predef._

class CassandraSimulation extends Simulation {
  val keyspace = "test"
  val table_name = "test_table"
  val session = CqlSession.builder().build()//Your C* session
  session.execute(s"""CREATE KEYSPACE IF NOT EXISTS $keyspace 
                      WITH replication = { 'class' : 'SimpleStrategy', 
                                          'replication_factor': '1'}""")
                                          
  session.execute(s"USE $keyspace")
  val cqlConfig = cql.session(session) //Initialize Gatling DSL with your session

  //Setup
  session.execute(s"""CREATE TABLE IF NOT EXISTS $table_name (
          id timeuuid,
          num int,
          str text,
          PRIMARY KEY (id)
        );
      """)
  //It's generally not advisable to use secondary indexes in you schema
  session.execute(f"""CREATE INDEX IF NOT EXISTS $table_name%s_num_idx 
                      ON $table_name%s (num)""")


  //Prepare your statement, we want to be effective, right?
  val prepared = session.prepare(s"""INSERT INTO $table_name 
                                      (id, num, str) 
                                      VALUES 
                                      (now(), ?, ?)""")

  val random = new util.Random
  val feeder = Iterator.continually( 
      // this feader will "feed" random data into our Sessions
      Map(
          "randomString" -> random.nextString(20), 
          "randomNum" -> random.nextInt()
          ))

  val scn = scenario("Two statements").repeat(1) { //Name your scenario
    feed(feeder)
    .exec(cql("simple SELECT") 
         // 'execute' can accept a string 
         // and understands Gatling expression language (EL), i.e. ${randomNum}
        .execute("SELECT * FROM test_table WHERE num = ${randomNum}")
        .check(rowCount.is(1)))
    .exec(cql("prepared INSERT")
         // alternatively 'execute' accepts a prepared statement
        .execute(prepared)
         // you need to provide parameters for that (EL is supported as well)
        .withParams(Integer.valueOf(random.nextInt()), "${randomString}")
        // and set a ConsistencyLevel optionally
        .consistencyLevel(ConsistencyLevel.ANY)) 
  }

  setUp(scn.inject(rampUsersPerSec(10) to 100 during (30.seconds)))
    .protocols(cqlConfig)

  after(session.close())
}

Installation

For the gatling-charts-highcharts-bundle setup

• Get a release TGZ from the Maven Central
• Unpack into Gatling folder: tar -xjf gatling-cql-3.9.0-1-bundle.tar.gz -C gatling-charts-highcharts-bundle-3.9.0/
• Run Gatling and you should see cassandra.CassandraSimulation in your simulations list

As a library for your project

Include gatling-cql as a dependency to your project. See the Maven Central Page for more information for you build tool.

Maven Example

You can run your simulations as a part of your build/CI process. See the Gatling Maven Plugin page for more details, please add the following dependency in your POM file.

    <dependencies>
        <dependency>
            <groupId>io.github.gatling-cql</groupId>
            <artifactId>gatling-cql</artifactId>
            <version>3.9.0-1</version>
        </dependency>
    </dependencies>

More Information

• https://gatling.io/docs/gatling/tutorials/quickstart/