Grails build-test-data Plugin

grailsbuild-test-data

plugin

created by Ted Naleid and Joe Hoover

Tuesday, July 14, 2009

creating test data with groovy is easy!


["Alice", "Bob", "Carol", "Dave"].each { new Author(name: it).save()}

iterators

closures

syntactic sugar


modeling your domain in grails is easy!


class Book { String title static belongsTo = [author: Author]}

class Author { String name static hasMany = [books: Book]}

a book belongs to an author

an author has many books


class User { String login

String password String email Date birthDate

static constraints = { login(size: 5..15, blank: false, unique: true)

password(size: 5..15, blank: false) email(email: true, blank: false) birthDate(max: new Date()) } }

constraints


def user = new User(login: “tnaleid”, password: “sekrit1”, birthDate: new Date() - (365 * 36)

).save()

test data must pass constraints


def user = new User(login: “tnaleid”, password: “sekrit1”, email: “[email protected]”,age: new Date() - (365 * 36)

).save()

whoops! missed an attribute!


mailto:[email protected]


def user = new User(login: “tnaleid”, password: “sekrit”, email: “[email protected]”,birthDate: new Date() - (365 * 36)

).save()

// service looks up user in DB by username and deletes itassertTrue userService.deleteByUsername(“tnaleid”)

constrained attributes are required even if your test doesn’t care about

them




problem multiplied by complex domain models


agile + code coverage = lots of tests


you need to add a new constraint...

what happens to all the tests?



creating maintainable test data is hard!


existing test datacreation strategies


copy/paste/modify for every

test method

void testTenDollarPurchase() { def author = new Author( name: “David Foster Wallace” ).save() Book book = new Book( author: author,

title: "The Pale King", published: new Date(), price: 10.00 as BigDecimal

).save() def ord = service.orderBook(book.id) //... test assertions}

void testTwentyDollarPurchase() { def author = new Author( name: “David Foster Wallace” ).save() Book book = new Book( author: author,

title: "Infinite Jest", published: new Date(), price: 20.00 as BigDecimal

).save() def ord = service.orderBook(book.id) //... test assertions}


def author

void setUp() { author = new Author( name: “David Foster Wallace” ).save()}

void testTenDollarPurchase() { Book book = new Book( author: author, title: "The Pale King", published: new Date(), price: 10.00 as BigDecimal ).save() def order = service.orderBook(book.id) //... test assertions}

void testTwentyDollarPurchase() { Book book = new Book( author: author, title: "Infinite Jest", published: new Date(), price: 20.00 as BigDecimal ).save() def result = service.orderBook(book.id) //... test assertions}

use setUp method to share objects

across tests


class AuthorObjectMother { static dfw() { return new Author( name: “David Foster Wallace” ).save() }}

class BookObjectMother { static thePaleKing() { return new Book( author: AuthorObjectMother.dfw(), title: “The Pale King”, published: new Date(), price: 10.00 as BigDecimal ).save() } static infiniteJest() { return new Book( author: AuthorObjectMother.dfw(), title: “Infinite Jest”, published: new Date(), price: 20.00 as BigDecimal ).save() }}

testTenDollarPurchase() { Book book = BookObjectMother.thePaleKing() def result = service.orderBook(book.id) //... test assertions}

void testTwentyDollarPurchase() { Book book = BookObjectMother.infiniteJest() def result = service.orderBook(book.id) //... test assertions}

object mother pattern


// fixtures/dfwBooks.groovy:fixture { davidFosterWallace(Author) { name = “David Foster Wallace” } thePaleKing(Book) { author = davidFosterWallace title = "The Pale King" published = new Date() price = 10.00 as BigDecimal } infiniteJest(Book) { author = davidFosterWallace title = "Infinite Jest" published = new Date() price = 20.00 as BigDecimal }}

// test class ...def fixtureLoadervoid testTenDollarPurchase() { fixtureLoader.load("dfwBooks") Book book = Book.findByTitle(“The Pale King”)

def result = service.orderBook(book.id) //... test assertions}

void testTenDollarPurchase() { fixtureLoader.load("dfwBooks") Book book = Book.findByTitle(“Infinite Jest”) def result = service.orderBook(book.id) //... test assertions}

builder DSL / test fixtures


all of these strategies strive to DRY up your test data

creation


but all of them repeat the same rules specified in the constraints


void testTenDollarPurchase() { Book book = new Book( price: 10.00 as BigDecimal ) mockDomain(Book, [book])

def order = service.orderBook(book.id) //...test assertions}

void testTwentyDollarPurchase() { Book book = new Book( price: 20.00 as BigDecimal ) mockDomain(Book, [book]) def result = service.orderBook(book) //... test assertions}

grails does have mocks ... but what

are they really testing?


void testPurchaseBookService() { def author = new Author(

name: "First Last", ).save()

Book book = new Book(author: author, title: "title", published: new Date(), price: 10.00 as BigDecimal

).save() def order = service.orderBook(book.id) //... test assertions}

what if we could turn this

void testPurchaseBookService() {Book book = Book.build( price: 10.00 as BigDecimal)

def result = service.orderBook(book)//... test assertions

}

into this


you can with the build-test-data plugin


build-test-data advantages


testing data documents what’s being tested


only specify values the test uses


test coupling is eliminated


you’re executing real GORM code paths


unrelated domain changes won’t break

your tests


build-test-data usage


class Author { String name static hasMany = [books: Book]}

class Book { String title static belongsTo = [author: Author]}

our domain


def book = Book.build()

assertNotNull book.authorassertNotNull book.title

just give me a book


def book = Book.build(title:“Infinite Jest”)

give me a book, but let me set the

title


def book = Book.build(author: Author.build(name: “Charlie Stross”))

let me tweak the book’s author


build-test-data features


‣ Domain objects (1..1, 1..N, N..N)

‣ Embedded domain objects

‣ String

‣ Boolean

‣ Number (Integer, Long, Float, etc)

‣ Byte

‣ Date

‣ Enum

‣ JodaTime

‣ Any other hibernate persistable class with a zero-argument constructor

build-test-data supports all

known attribute types


automatic constraint support

‣ nullable

‣ blank

‣ inList

‣ max

‣ maxSize

‣ min

‣ minSize

‣ range

‣ scale

‣ size

‣ url

‣ creditCard

‣ email


manual constraint support

‣ matches (regular expressions)

‣ validator (user-defined constraint)

‣ unique


// grails-app/conf/TestDataConfig.groovy

testDataConfig { sampleData = { Publisher { name = “Pragmatic Bookshelf” // default unless overridden } }}

configuration file lets you customize static attribute values


// grails-app/conf/TestDataConfig.groovy

testDataConfig { sampleData = { ‘com.example.Hotel’ { def i = 1 name = {-> “name${i++}” } // “name1”, “name2”, ... “nameN” } }}

configuration file lets you customize dynamic attribute values


grails install-plugin build-test-data

build-test-data installation


live coding demo


linksbuild-test-data home

http://bitbucket.org/tednaleid/grails-test-data/wiki/Home

intro blog posthttp://naleid.com/blog/2009/04/14/grails-build-test-data-01-plugin-released/

photo creditshttp://www.flickr.com/photos/kaptainkobold/3406169798/in/set-1058884

http://commons.wikimedia.org/wiki/File:Domain_model.png

http://www.flickr.com/photos/nickwheeleroz/2474196275/in/photostream




http://naleid.com/blog/2009/04/14/grails-build-test-data-01-plugin-released/

http://naleid.com/blog/2009/04/14/grails-build-test-data-01-plugin-released/

http://livepage.apple.com/

http://livepage.apple.com/





Questions?


Grails build-test-data Plugin

Technology

new book author

book book

new date

new userlogin

new authorname

new constraint

test assertions

class user