
com.websudos.phantom.example.basics.SimpleRecipes.scala Maven / Gradle / Ivy
/*
* Copyright 2013-2015 Websudos, Limited.
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* - Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* - Explicit consent must be obtained from the copyright owner, Outworkers Limited before any redistribution is made.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
package com.websudos.phantom.example.basics
import java.util.UUID
import scala.concurrent.{ Future => ScalaFuture }
import org.joda.time.DateTime
import com.datastax.driver.core.{ ResultSet, Row }
import com.websudos.phantom.dsl._
import com.websudos.phantom.reactivestreams._
import com.twitter.conversions.time._
/**
* In this example we will create a simple table storing recipes.
* Data modeling with com.websudos.phantom is trivial and covers some of the more advanced features of Cassandra.
*
* Phantom will auto-generate the CQL3 table definition from your Scala code.
* And you can automatically insert the schema during tests or even live environments.
*
* This is a very straightforward example, with a non composite Partition key
*/
case class Recipe(
id: UUID,
name: String,
title: String,
author: String,
description: String,
ingredients: Set[String],
props: Map[String, String],
timestamp: DateTime
)
// You can seal the class and only allow importing the companion object.
// The companion object is where you would implement your custom methods.
// Keep reading for examples.
sealed class Recipes extends CassandraTable[Recipes, Recipe] {
object id extends UUIDColumn(this) with PartitionKey[UUID] {
// You can override the name of your key to whatever you like.
// The default will be the name used for the object, in this case "id".
override lazy val name = "the_primary_key"
}
// Now we define a column for each field in our case class.
object name extends StringColumn(this)
object title extends StringColumn(this)
object author extends StringColumn(this)
object description extends StringColumn(this)
// Custom data types can be stored easily.
// Cassandra collections target a small number of items, but usage is trivial.
object ingredients extends SetColumn[String](this)
object props extends MapColumn[String, String](this)
object timestamp extends DateTimeColumn(this)
// Now the mapping function, transforming a row into a custom type.
// This is a bit of boilerplate, but it's one time only and very short.
def fromRow(row: Row): Recipe = {
Recipe(
id(row),
name(row),
title(row),
author(row),
description(row),
ingredients(row),
props(row),
timestamp(row)
)
}
}
abstract class ConcreteRecipes extends Recipes with RootConnector {
// you can even rename the table in the schema to whatever you like.
override lazy val tableName = "my_custom_table"
// Inserting has a bit of boilerplate on its on.
// But it's almost always a once per table thing, hopefully bearable.
// Whatever values you leave out will be inserted as nulls into Cassandra.
def insertNewRecord(recipe: Recipe): ScalaFuture[ResultSet] = {
insert.value(_.id, recipe.id)
.value(_.author, recipe.author)
.value(_.description, recipe.description)
.value(_.ingredients, recipe.ingredients)
.value(_.name, recipe.name)
.value(_.props, recipe.props)
.value(_.timestamp, recipe.timestamp)
.ttl(150.minutes.inSeconds) // you can use TTL if you want to.
.future()
}
// now you have the full power of Cassandra in really cool one liners.
// The future will do all the heavy lifting for you.
// If there is an error you get a failed Future.
// If there is no matching record you get a None.
// The "one" method will select a single record, as it's name says.
// It will always have a LIMIT 1 in the query sent to Cassandra.
// select.where(_.id eqs UUID.randomUUID()).one() translates to
// SELECT * FROM my_custom_table WHERE id = the_id_value LIMIT 1;
def getRecipeById(id: UUID): ScalaFuture[Option[Recipe]] = {
select.where(_.id eqs id).one()
}
// com.websudos.phantom allows partial selects from any query.
// this is currently limited to 22 fields.
def getRecipeIngredients(id: UUID): ScalaFuture[Option[Set[String]]] = {
select(_.ingredients).where(_.id eqs id).one()
}
// Because you are using a partition key, you can successfully using ordering
// And you can paginate your records.
// That's it, a really cool one liner.
// The fetch method will collect an asynchronous lazy iterator into a Seq.
// It's a good way to avoid boilerplate when retrieving a small number of items.
def getRecipesPage(start: UUID, limit: Int): ScalaFuture[Seq[Recipe]] = {
select.where(_.id gtToken start).limit(limit).fetch()
}
// The fetchEnumerator method is the real power behind the scenes.
// You can retrieve a whole table, even with billions of records, in a single query.
// Phantom will collect them into an asynchronous, lazy iterator with very low memory foot print.
// Enumerators, iterators and iteratees are based on Play iteratees.
// You can keep the async behaviour or collect through the Iteratee.
def getEntireTable: ScalaFuture[Seq[Recipe]] = {
select.fetchEnumerator() run Iteratee.collect()
}
// com.websudos.phantom supports a few more Iteratee methods.
// However, if you are looking to guarantee ordering and paginate "the old way"
// You need an OrderPreservingPartitioner.
def getRecipePage(start: Int, limit: Int): ScalaFuture[Iterator[Recipe]] = {
select.fetchEnumerator() run Iteratee.slice(start, limit)
}
// Updating records is also really easy.
// Updating one record is done like this
def updateRecipeAuthor(id: UUID, author: String): ScalaFuture[ResultSet] = {
update.where(_.id eqs id).modify(_.author setTo author).future()
}
// Updating records is also really easy.
// Updating multiple fields at the same time is also easy.
def updateRecipeAuthorAndName(id: UUID, name: String, author: String): ScalaFuture[ResultSet] = {
update.where(_.id eqs id)
.modify(_.name setTo name)
.and(_.author setTo author)
.future()
}
// Deleting records has the same restrictions and selecting.
// If something is non primary, you cannot have it in a where clause.
def deleteRecipeById(id: UUID): ScalaFuture[ResultSet] = {
delete.where(_.id eqs id).future()
}
}
© 2015 - 2025 Weber Informatics LLC | Privacy Policy