(Quick Reference)

3 Upgrading from the previous versions

Version: 6.2.1

3.1Upgrading from Grails 5 to Grails 6

3.2Upgrading from Grails 4 to Grails 5

3.3Upgrading from Grails 3.3.x to Grails 4

3 Upgrading from the previous versions

3.1 Upgrading from Grails 5 to Grails 6

Upgrade Instructions for Grails and Related Dependencies

To ensure compatibility with Grails 6, you must update the following versions in your project:

1. Java 11 as Baseline:

Starting from Grails 6, Java 11 serves as the baseline requirement for the framework. When upgrading to Grails 6, ensure that your project is configured to use Java 11. This compatibility with Java 11 allows you to take advantage of the latest features, security enhancements, and performance improvements provided by Java 11.

Please make sure to update your project’s Java version to 11 before proceeding with the Grails 6 upgrade. Doing so will ensure a seamless transition to the latest version of Grails and enable you to enjoy all the benefits that Java 11 has to offer.

2. The New Grails CLI:

Grails 6 comes with a completely revamped and highly efficient Command Line Interface (CLI) that enables you to generate applications and plugins at a remarkable speed. For instance, you can now use the new CLI to create a new Grails 6 application with the following command:

grails create-app my-app

The new CLI also allows you to generate plugins easily. For example, to create a new plugin named "my-plugin," you can use the following command:

grails create-plugin my-plugin

One notable improvement in Grails 6 is that it no longer supports certain commands that performed redundant tasks, such as the outdated grails run-app command. Instead, it recommends using the Gradle bootRun task for running your application, which offers better performance and functionality.

For example, to run your Grails 6 application, you can use the following command:

./gradlew bootRun

As a result of these improvements, the new CLI provides a more streamlined and efficient way to work with Grails applications and plugins.

Overall, Grails 6 offers a significantly improved development experience with its new CLI, optimized commands, and advanced features for generating applications and plugins.

3. Setting Grails Version and Grails Gradle Plugin:

To upgrade to Grails 6, it’s important to configure the appropriate versions in the gradle.properties file as shown below:

gradle.properties

grailsVersion=6.0.0
grailsGradlePluginVersion=6.0.0

By specifying the above versions, you’ll gain access to the latest features, improvements, and bug fixes introduced in Grails 6. Upgrading to this version empowers your application with enhanced performance and improved security. Additionally, it allows you to leverage the latest advancements in the Grails framework for a more efficient and secure development experience.

4. GORM Version:

If your project utilizes GORM, ensure to update the version in the gradle.properties file as demonstrated below:

gradle.properties

gormVersion=8.0.0

By upgrading to GORM 8.0.0, you will benefit from essential updates and optimizations. This upgrade guarantees seamless interactions with your database and enhances your data management experience. Staying current with GORM allows you to take advantage of the latest database features and improvements, thereby optimizing the performance and functionality of your application.

5. Gradle Version:

Grails 6 uses Gradle 7.6.2 which offers performance improvements, bug fixes, and new features over previous versions. Upgrading to the latest Gradle version helps accelerate your build processes and ensures compatibility with other dependencies.

5.1. Upgrade to Gradle 7.6.2

Run the following command to update the Gradle wrapper to the desired version (e.g., Gradle 7.6.2):

./gradlew wrapper --gradle-version 7.6.2

This command will download the specified Gradle version and update the Gradle wrapper settings in your project.

5.2. Check Gradle Version:

After the command finishes, you can verify that the Gradle version has been updated by checking the gradle-wrapper.properties file located in the gradle/wrapper directory. The distributionUrl in the file should now point to the Gradle 7.6.2 distribution:

distributionUrl=https\://services.gradle.org/distributions/gradle-7.6.2-bin.zip

5.3. Build the Project:

After updating the Gradle wrapper, you can now build your Grails project using the updated Gradle version:

./gradlew build

This will initiate the build process with the new Gradle version.

6. Embracing Modern Plugin Management with Grails 6

In Gradle, there are two main ways to add plugins to your project: the plugins block and the apply plugin statement.

Grails 6 introduces a significant change in how plugins are managed by adopting the Gradle plugins block instead of the traditional apply plugin statements. This shift streamlines the project’s build configuration and brings it more in line with modern Gradle conventions. New Grails projects will now utilize the plugins block to manage plugin dependencies and configurations.

Using the plugins Block in Grails 6:

With the new approach, adding plugins to a Grails 6 project is more explicit and organized. In your build.gradle file, you can declare plugins within the plugins block, specifying the plugin’s ID and version.

Here’s an example of adding the views-json plugin using the plugins block:

build.gradle

plugins {
    id 'org.grails.plugins.views-json' version '3.0.0'
}

Managing Multiple Plugins:

The plugins block allows you to add multiple plugins, each on its own line. This enhances clarity and makes it easier to manage plugin dependencies.

build.gradle

plugins {
    id 'org.grails.plugins.views-json' version '3.0.0'
    // Add other plugins as needed
}

Moving Older Applications to the New Approach:

If you are migrating an older Grails application to Grails 6, you can update the plugin declarations from apply plugin to the plugins block. For example, if your previous application used the views-json plugin, you can modify the build.gradle as follows:

Before (Using apply plugin):

build.gradle

apply plugin: 'org.grails.plugins.views-json'

After (Using plugins Block in Grails 6):

build.gradle

plugins {
    id 'org.grails.plugins.views-json' version '3.0.0'
}

By migrating to the plugins block, your Grails 6 project will adhere to modern Gradle conventions, making it easier to manage plugin dependencies and configurations. This new approach maintains consistency and enhances the overall structure of the project, ensuring a smoother and more efficient development process.

6.2. Use the pluginManagement Block

Moving from apply plugin in the build.gradle file to the pluginManagement block in the settings.gradle file is a significant change introduced in Grails 6. This change is part of Grails' effort to adopt the Gradle pluginManagement approach for better plugin version control and consistency across projects.

In the previous versions of Grails (before Grails 6), developers used to apply plugins directly in the build.gradle file using the apply plugin syntax. For example:

build.gradle

buildscript {
    repositories {
        maven { url "https://plugins.gradle.org/m2/" }
        maven { url "https://repo.grails.org/grails/core" }
    }
    dependencies {
        classpath "org.grails:grails-gradle-plugin:$grailsGradlePluginVersion"
        classpath "org.grails.plugins:hibernate5:7.3.0"
        classpath "org.grails.plugins:views-gradle:2.3.2"
    }
}

version "0.1"
group "hellorestapi"

apply plugin:"eclipse"
apply plugin:"idea"
apply plugin:"war"
apply plugin:"org.grails.grails-web"
apply plugin:"org.grails.plugins.views-json"

However, with Grails 6, the recommended practice is to move plugin declarations to the pluginManagement block in the settings.gradle file. The pluginManagement block acts as a central place to manage plugin versions for all projects within a multi-project build.

Configuring Plugins in the pluginManagement Block:

Here’s how you can declare the views-json plugin in the pluginManagement block:

Open the settings.gradle file in your Grails 6 project.
Add the pluginManagement block with the views-json plugin declaration:

settings.gradle

pluginManagement {
    repositories {
        // Add the Grails plugin repository to resolve the views-json plugin
        maven { url "https://repo.grails.org/grails/core" }
        // Other repositories can be added here if needed
    }

    // Declare the views-json plugin and its version
    plugins {
        id 'org.grails.plugins.views-json' version '3.0.0'
        // Other plugins can be declared here
    }
}

By including the views-json plugin in the pluginManagement block, Grails 6 will ensure that all projects within the multi-project build use the specified version of the views-json plugin. This promotes consistency in JSON rendering across different projects and simplifies maintenance and version control.

Moving Older Applications to the New Approach:

If you are migrating an older Grails application to Grails 6, you can update the plugin declarations from apply plugin to the plugins block in the build.gradle file, as shown in the previous section.

By adopting the pluginManagement block and declaring the views-json plugin in the settings.gradle file, you ensure consistent usage of the plugin across all projects in the Grails 6 ecosystem. This approach simplifies plugin version control and improves the overall development experience when working with JSON responses in your Grails applications.

6.3 Grails Adoption of "buildSrc" Folder for Buildscript Dependencies

In previous versions of Grails (before Grails 6), managing buildscript dependencies, such as the views-gradle plugin, was typically done directly in the main build.gradle file. This enables Gradle compilation of JSON views for production environment. Developers would define the repositories and dependencies needed for the buildscript within the buildscript block:

build.gradle

buildscript {
    repositories {
        mavenCentral()
    }
    dependencies {
        // Example: views-gradle plugin
        classpath "org.grails.plugins:views-gradle:3.0.0"
    }
}

// Apply the views-json plugin
apply plugin: 'views-json'

// Other configurations and dependencies

This approach meant that the buildscript dependencies were mixed with the rest of the project’s configurations, making the build.gradle file longer and potentially harder to maintain. As a result, the buildscript section might become cluttered with various plugin dependencies and other build logic.

With the introduction of Grails 6, there is a significant improvement in managing buildscript dependencies through the use of the buildSrc folder. This dedicated folder provides a more organized approach to handle buildscript dependencies, custom Gradle plugins, and extensions specific to the project.

Benefits of Grails 6 Adoption of "buildSrc" Folder

Modular Build Configuration: The buildSrc folder acts as a separate mini-project within your Grails application, allowing you to encapsulate build logic, plugins, and dependencies. This separation of concerns improves the organization and modularity of the build configuration.
Streamlined Buildscript Management: By moving buildscript dependencies to buildSrc, you can keep the main build.gradle file clean and focused on the application’s specific requirements. This reduces clutter and promotes a more concise and clear build script.
Better Collaboration: The buildSrc approach simplifies collaboration within development teams. Build logic can be centralized and shared across projects, enabling a consistent and efficient development workflow.

Update from Grails 5

The new Grails 6 application uses buildSrc/build.gradle. The buildSrc directory can host a build script if additional configuration is needed (e.g. to apply plugins or to declare dependencies). The buildSrc folder in a Grails project follows a specific tree layout, which includes the build.gradle file. Here’s how the tree layout looks like:

buildSrc/
├── build.gradle
└── src/
    └── main/
        └── groovy/

Let’s walk through how to manage the views-gradle plugin using the buildSrc folder in Grails 6:

Step 1: Create buildSrc Folder:

In the root directory of your Grails 6 project, create a new folder named buildSrc.

Step 2: Add buildSrc Script:

Inside the buildSrc folder, create a build.gradle file and specify the views-gradle plugin dependency:

buildSrc/build.gradle

repositories {
    mavenCentral()
}

dependencies {
    implementation "org.grails.plugins:views-gradle:3.0.0"
}

Step 3: Remove apply plugin Statement:

In the main build.gradle file, remove the buildscript block and the apply plugin statement related to views-gradle, as it is now managed in the buildSrc folder:

build.gradle

buildscript {
    repositories {
        mavenCentral()
    }
    dependencies {
        classpath "org.grails.plugins:views-gradle:3.0.0"
    }
}

// No need to apply views-json plugin here
// Remove the apply plugin statement for views-json if it was previously present
apply plugin: 'views-json'

// ... Other configurations and dependencies

By using the buildSrc folder, developers can separate buildscript dependencies and custom plugin configurations from the main build.gradle file. This leads to a cleaner and more concise build script, which is easier to maintain and understand. Additionally, the buildSrc approach encourages modularity, as build logic and custom plugins can be centralized and shared across projects, fostering better collaboration and consistency within development teams.

7. GORM for MongoDB Sync Driver:

The GORM for MongoDB is updated to support the latest mongodb-driver-sync. If you are using GORM for MongoDB and making use of specific MongoDB Driver or low-level Mongo API features, consider checking the Upgrading to the 4.0 Driver guide.

This update ensures seamless integration with MongoDB, access to new features, and improved performance while interacting with your MongoDB database.

8. Asset Pipeline Plugin:

In Grails 6, there is an update to the Asset Pipeline Plugin, which is now version 4.3.0. The Asset Pipeline Plugin is a crucial component in Grails applications, responsible for managing frontend assets like stylesheets, JavaScript files, and images. The update to version 4.3.0 brings several improvements and new features to enhance the management and processing of frontend assets in your Grails projects.

The asset-pipeline plugin 4.3.0 offers new features for managing and processing your frontend assets, ensuring they are efficiently bundled and served to your users.

9. Spring 5.3:

Grails 6 is built on Spring 5.3.27. If your project uses Spring-specific features, refer to the Upgrading to Spring 5.3 guide.

Spring 5.3 introduces enhancements and fixes to the Spring framework, providing you with the latest improvements in dependency injection, web frameworks, and other Spring-related functionalities.

10. Spring Boot 2.7:

Grails 6 updates to Spring Boot 2.7. For more information, consult the Spring Boot 2.7 Release Notes

Spring Boot 2.7 comes with new features, performance enhancements, and compatibility improvements, making it a solid foundation for your Grails application.

11. Micronaut 3.9.3:

Grails 6 is shipped with Micronaut 3.9.3. If you are using specific Micronaut features, refer to the Upgrading to Micronaut 3.x guide.

Micronaut 3.9.3 brings new capabilities, improvements, and bug fixes, empowering your application with a powerful and lightweight microservices framework.

12. Micronaut for Spring 4.5.1:

Grails 6 is updated to use Micronaut for Spring 4.5.1. For more information, check out the release notes.

Micronaut for Spring 4.5.1 provides seamless integration between Micronaut and Spring, allowing you to leverage the strengths of both frameworks in your Grails project.

3.2 Upgrading from Grails 4 to Grails 5

Bump up Grails Version

You will need to upgrade your Grails version defined in gradle.properties as:

gradle.properties

...
grailsVersion=5.2.0
...

Apache Groovy 3.0.7

Grails 5.1.1 provide support for Groovy 3. We would recommend you to please check the Release notes for Groovy 3 to update your application in case you are using a specific feature which might not work in Groovy 3.

Define groovyVersion in gradle.properties to force the application to use Groovy 3.

Grails 5.1 app’s gradle.properties

gradle.properties

...
groovyVersion=3.0.7
...

Bump up GORM Version

If you were using GORM, you will need to update the version defined in gradle.properties as:

gradle.properties

...
gormVersion=7.2.0
...

Bump up gradle version

Grails 5.2.x uses gradle 7.2

gradle-wrapper.properties

...
distributionUrl=https\://services.gradle.org/distributions/gradle-7.2-bin.zip
...

Also you can run this command

./gradlew wrapper --gradle-version 7.2

GORM for MonogDB Sync Driver

The GORM for MongoDB is updated to support latest mongodb-driver-sync. If you are using GORM for MongoDB and doing something specific to MongoDB Driver or low level Mongo API then you might want to take a look at Upgrading to the 4.0 Driver

Bump up Asset Pipeline plugin version

The previous version of asset-pipeline is not supported with Grails 5.0 as it is compiled with a version of Groovy which is binary incompatible with Groovy 3. So, please update the plugin version to 3.2.4.

Disabled StringCharArrayAccessor by default

The previous version of Grails use the StringCharArrayAccessor which is enabled by default and provides optimized access to java.lang.String internals. In Grails 5.0 it is disabled by default but you can enable it by setting a system property with name stringchararrayaccessor.disabled and value false.

Enabling StringCharArrayAccessor would show IllegalReflectiveAccess warnings as it uses reflection to do the optimizations.

Changes in profile.yml and feature.yml files in Grails Profiles

The format of how dependencies are defined in features and profiles has been changed. See the section on Application Profiles for more information.

Deprecation of dot navigation of Grails configuration

In order to reduce complexity, improve performance, and increase maintainability, accessing configuration through dot notation (config.a.b.c) has been deprecated. This functionality will be removed in a future release.

Also, you would see a warning message if you are accessing configuration through the dot notation.

The recommended way to access configuration is:

grailsApplication.config.getProperty("hola", String.class)

Deprecated Classes

Spring 5.3

Grails 5.0.0.RC1 is built on Spring 5.3.2 See the Upgrading to Spring 5.3 if you are using Spring specific features.

Spring Boot 2.4

Grails 5.1.1 updates to Spring Boot 2.6. Please check Spring Boot 2.6 Release Notes for more information.

Micronaut 3.2.0

Grails 5.1.1 is shipped with Micronaut 3.2.0. Please check the Upgrading to Micronaut 3.x if you are using a specific feature.

Micronaut for Spring 4.0.1

Grails 5.1.1 is updated to Micronaut for Spring 4.0.1, please check out release notes for more information.

Gradle 7.x

Compile dependency configuration as well as others have been removed from Gradle 7.x. In previous version they were deprecated.

Replace configurations:

build.gradle

...
 compile -> implementation
 testCompile -> testImplementation
 runtime -> runtimeOnly
...

More information in Gradle upgrade docs Gradle upgrade docs

Plugins in multi-project setup

If you have grails plugins as part of multi-project builds you should also replace the compile with implementation configuration.

Additionally if your main application relied on the dependencies declared by the plugin you need to apply further changes.

To make the dependencies available again you have to declare them with api configuration. You also have to apply the java-library gradle plugin in your plugin project.

More information gradle java-library-plugin

3.3 Upgrading from Grails 3.3.x to Grails 4

Bump up Grails Version

You will need to upgrade your Grails version defined in gradle.properties.

Grails 3 app’s gradle.properties

gradle.properties

...
grailsVersion=3.3.8
...

Grails 4 app’s gradle.properties

gradle.properties

...
grailsVersion=4.0.4
...

Bump up GORM Version

If you were using GORM, you will need to update the version defined in gradle.properties.

Grails 3 app’s gradle.properties

gradle.properties

...
gormVersion=6.1.10.RELEASE
...

Grails 4 app’s gradle.properties

gradle.properties

...
gormVersion=7.0.4
...

Move GORM DSL Entries to runtime.groovy

GORM DSL entries should be move to runtime.groovy. For instance, using following GORM configuration in the application.groovy is not supported and will break the application:

grails.gorm.default.mapping = {
    id generator: 'identity'
}

Spring 5 and Spring Boot 2.1

Grails 4.0 is built on Spring 5 and Spring Boot 2.1. See the migration guide and release notes if you are using Spring specific features.

Hibernate 5.4 and GORM 7.x

Grails 4.x supports a minimum version of Hibernate 5.4 and GORM 7.x. Several changes have been made to GORM to support the newer version of Hibernate and simplify GORM itself.

The details of these changes are covered in the GORM upgrade documentation.

Spring Boot 2.1 Actuator

Please check the Spring Boot Actuator documentation since it has changed substantially from Spring Boot 1.5 the version Grails 3.x used.

If you had configuration such as:

grails-app/conf/application.yml - Grails 3.3.x

endpoints:
    enabled: false
    jmx:
        enabled: true
        unique-names: true

replace it with:

grails-app/conf/application.yml - Grails 4.x

spring:
    jmx:
        unique-names: true
management:
    endpoints:
        enabled-by-default: false

Spring Boot Developer Tools and Spring Loaded

Previous versions of Grails used a reloading agent called Spring Loaded. Since this library is no longer maintained and does not support Java 11 support for Spring Loaded has been removed.

As a replacement, Grails 4 applications include Spring Boot Developer Tools dependencies in the build.gradle build script. If you are migrating a Grails 3.x app, please include the following set of dependencies:

build.gradle

.
..
...
configurations {
    developmentOnly
    runtimeClasspath {
        extendsFrom developmentOnly
    }
}

dependencies {
        developmentOnly("org.springframework.boot:spring-boot-devtools")
        ...
        ..
}
...
..
.

Also you should configure the necessary excludes for Spring Developer Tools in application.yml:

spring:
    devtools:
        restart:
            exclude:
                - grails-app/views/**
                - grails-app/i18n/**
                - grails-app/conf/**

The above configuration prevents the server from restarting when views or message bundles are changed.

You can use Spring Developer Tools in combination with a browser extension such as the Chrome LiveReload extension to get automatic browser refresh when you change anything in your Grails application.

Spring Boot Gradle Plugin Changes

Grails 4 is built on top of Spring Boot 2.1. Grails 3 apps were built on top of Spring Boot 1.x.

Your Grails 3 app’s build.gradle may have such configuration:

build.gradle

bootRun {
    addResources = true
    ...
}

Grails 4 apps are built on top of Spring Boot 2.1. Starting from Spring Boot 2.0, the addResources property no longer exists. Instead, you need to set the sourceResources property to the source set that you want to use. Typically that’s sourceSets.main. This is described in the Spring Boot Gradle plugin’s documentation.

Your Grails 4 app’s build.gradle can be configured:

build.gradle

bootRun {
        sourceResources sourceSets.main
    ...
}

Building executable jars for Grails Plugins

Spring Boot’s new Gradle Plugin:

The bootRepackage task has been replaced with bootJar and bootWar tasks for building executable jars and wars respectively. Both tasks extend their equivalent standard Gradle jar or war task, giving you access to all of the usual configuration options and behaviour.

If you had configuration such as:

build.gradle | Grails 3

// enable if you wish to package this plugin as a standalone application
bootRepackage.enabled = false

replace it with:

build.gradle | Grails 4

// enable if you wish to package this plugin as a standalone application
bootJar.enabled = false

Upgrading to Gradle 5

Grails 3 apps by default used Gradle 3.5. Grails 4 apps use Gradle 5.

To upgrade to Gradle 5 execute:

./gradlew wrapper --gradle-version 5.0

Due to changes in Gradle 5, transitive dependencies are no longer resolved for plugins. If your project makes use of a plugin that has transitive dependencies, you will need to add those explicitly to your build.gradle file.

If you customized your app’s build, other migrations may be necessary. Please check Gradle Upgrading your build documentation. Especially notice, that default Gradle daemon now starts with 512MB of heap instead of 1GB. Please check Default memory settings changed documentation.

Groovy language update to 2.5.6

Keep in mind, that with grails 4.0.x there is a minor groovy language upgrade (e.g. 3.3.9. used groovy 2.4.x), which requires a couple of changes, that are immediately obvious when trying to compile your source code. However there are also issues with changed implementations of core linkedlist functions! Check an overview of the breaking changes here: Breaking changes of Groovy 2.5

Removed date helper functions

Most common issue is that date util functions have been moved to individual project, e.g new Date().format("ddMMyyyy") no longer works without adding:

build.gradle

dependencies {
    implementation "org.codehaus.groovy:groovy-dateutil:3.0.4"
}

Changed linked list method implementations

Check whether you are using the groovy version of linkedlist implementations:

[].pop() - will no longer remove the last, but the first element of the list. Replace it with [].removeLast() is recommended.
[].push(..) - will no longer add to the end, but to the beginning of the list. Replace it with [].add(..) is recommended.

H2 Web Console

Spring Boot 2.1 includes native support for the H2 database web console. Since this is already included in Spring Boot the equivalent feature has been removed from Grails. The H2 console is therefore now available at /h2-console instead of the previous URI of /dbconsole. See Using H2’s Web Console in the Spring Boot documentation for more information.

Upgrade Hibernate

If you were using GORM for Hibernate implementation in your Grails 3 app, you will need to upgrade to Hibernate 5.4.

A Grails 3 build.gradle such as:

build.gradle

dependencies {
...
  implementation "org.grails.plugins:hibernate5"
  implementation "org.hibernate:hibernate-core:5.1.5.Final"
}

will be in Grails 4:

build.gradle

dependencies {
...
  implementation "org.grails.plugins:hibernate5"
  implementation "org.hibernate:hibernate-core:5.4.0.Final"
}

Migrating to Geb 2.3

Geb 1.1.x (a JDK 1.7 compatible version) was the version shipped by default with Grails 3. Grails 4 is no longer compatible with Java 1.7. You should migrate to Geb 2.3.

In Grails 3, if your build.gradle looks like:

build.gradle

dependencies {
 testCompile "org.grails.plugins:geb:1.1.2"
 testRuntime "org.seleniumhq.selenium:selenium-htmlunit-driver:2.47.1"
 testRuntime "net.sourceforge.htmlunit:htmlunit:2.18"
}

In Grails 4, you should replace it with:

build.gradle

buildscript {
    repositories {
       ...
    }
    dependencies {
        ...
        classpath "gradle.plugin.com.energizedwork.webdriver-binaries:webdriver-binaries-gradle-plugin:$webdriverBinariesVersion" (1)
    }
}
...
..

repositories {
  ...
}

apply plugin:"idea"
...
...
apply plugin:"com.energizedwork.webdriver-binaries" (1)


dependencies {
...
    testCompile "org.grails.plugins:geb" (4)
    testRuntime "org.seleniumhq.selenium:selenium-chrome-driver:$seleniumVersion"  (5)
    testRuntime "org.seleniumhq.selenium:selenium-firefox-driver:$seleniumVersion" (5)
    testRuntime "org.seleniumhq.selenium:selenium-safari-driver:$seleniumSafariDriverVersion" (5)

    testCompile "org.seleniumhq.selenium:selenium-remote-driver:$seleniumVersion" (5)
    testCompile "org.seleniumhq.selenium:selenium-api:$seleniumVersion" (5)
    testCompile "org.seleniumhq.selenium:selenium-support:$seleniumVersion" (5)
}

webdriverBinaries {
    chromedriver "$chromeDriverVersion" (2)
    geckodriver "$geckodriverVersion" (3)
}

tasks.withType(Test) {
    systemProperty "geb.env", System.getProperty('geb.env')
    systemProperty "geb.build.reportsDir", reporting.file("geb/integrationTest")
    systemProperty "webdriver.chrome.driver", System.getProperty('webdriver.chrome.driver')
    systemProperty "webdriver.gecko.driver", System.getProperty('webdriver.gecko.driver')
}

gradle.properties

gebVersion=2.3
seleniumVersion=3.12.0
webdriverBinariesVersion=1.4
hibernateCoreVersion=5.1.5.Final
chromeDriverVersion=2.44 (2)
geckodriverVersion=0.23.0 (3)
seleniumSafariDriverVersion=3.14.0

1	Includes Webdriver binaries Gradle plugin.
2	Set the appropriate Webdriver for Chrome version.
3	Set the appropriate Webdriver for Firefox version.
4	Includes the Grails Geb Plugin dependency which has a transitive dependency to `geb-spock`. This is the dependency necessary to work with Geb and Spock.
5	Selenium and different driver dependencies.

Create also a Geb Configuration file at src/integration-test/resources/GebConfig.groovy.

src/integration-test/resources/GebConfig.groovy

import org.openqa.selenium.chrome.ChromeDriver
import org.openqa.selenium.chrome.ChromeOptions
import org.openqa.selenium.firefox.FirefoxDriver
import org.openqa.selenium.firefox.FirefoxOptions
import org.openqa.selenium.safari.SafariDriver

environments {

    // You need to configure in Safari -> Develop -> Allowed Remote Automation
    safari {
        driver = { new SafariDriver() }
    }

    // run via “./gradlew -Dgeb.env=chrome iT”
    chrome {
        driver = { new ChromeDriver() }
    }

    // run via “./gradlew -Dgeb.env=chromeHeadless iT”
    chromeHeadless {
        driver = {
            ChromeOptions o = new ChromeOptions()
            o.addArguments('headless')
            new ChromeDriver(o)
        }
    }

    // run via “./gradlew -Dgeb.env=firefoxHeadless iT”
    firefoxHeadless {
        driver = {
            FirefoxOptions o = new FirefoxOptions()
            o.addArguments('-headless')
            new FirefoxDriver(o)
        }
    }

    // run via “./gradlew -Dgeb.env=firefox iT”
    firefox {
        driver = { new FirefoxDriver() }
    }
}

Deprecated classes

The following classes, which were deprecated in Grails 3.x, have been removed in Grails 4. Please, check the list below to find a suitable replacement:

Removed Class

Alternative

org.grails.datastore.gorm.validation.constraints.UniqueConstraint

org.grails.datastore.gorm.validation.constraints.builtin.UniqueConstraint

grails.util.BuildScope

grails.transaction.GrailsTransactionTemplate

grails.gorm.transactions.GrailsTransactionTemplate

org.grails.transaction.transform.RollbackTransform

org.grails.datastore.gorm.transactions.transform.RollbackTransform

grails.transaction.NotTransactional

grails.gorm.transactions.NotTransactional

grails.transaction.Rollback

grails.gorm.transactions.Rollback

grails.transaction.Transactional

grails.gorm.transactions.Transactional

org.grails.config.FlatConfig

org.grails.core.metaclass.MetaClassEnhancer

Use traits instead.

org.grails.core.util.ClassPropertyFetcher

org.grails.datastore.mapping.reflect.ClassPropertyFetcher

org.grails.transaction.transform.TransactionalTransform

org.grails.datastore.gorm.transactions.transform.TransactionalTransform

grails.core.ComponentCapableDomainClass

grails.core.GrailsDomainClassProperty

Use the org.grails.datastore.mapping.model.MappingContext API instead

org.grails.core.DefaultGrailsDomainClassProperty

org.grails.core.MetaGrailsDomainClassProperty

org.grails.core.support.GrailsDomainConfigurationUtil

Use the org.grails.datastore.mapping.model.MappingContext and org.grails.datastore.mapping.model.MappingFactory APIs instead

org.grails.plugins.domain.DomainClassPluginSupport

org.grails.plugins.domain.support.GormApiSupport

org.grails.plugins.domain.support.GrailsDomainClassCleaner

Handled by org.grails.datastore.mapping.model.MappingContext now

grails.validation.AbstractConstraint

Use org.grails.datastore.gorm.validation.constraints.AbstractConstraint instead

grails.validation.AbstractVetoingConstraint

org.grails.datastore.gorm.validation.constraints.AbstractVetoingConstraint

grails.validation.CascadingValidator

grails.gorm.validation.CascadingValidator

grails.validation.ConstrainedProperty

grails.gorm.validation.ConstrainedProperty

grails.validation.Constraint

grails.gorm.validation.Constraint

grails.validation.ConstraintFactory

org.grails.datastore.gorm.validation.constraints.factory.ConstraintFactory

grails.validation.VetoingConstraint

grails.gorm.validation.VetoingConstraint

grails.validation.ConstraintException

org.grails.validation.BlankConstraint

org.grails.datastore.gorm.validation.constraints.BlankConstraint

org.grails.validation.ConstrainedPropertyBuilder

org.grails.datastore.gorm.validation.constraints.builder.ConstrainedPropertyBuilder

org.grails.validation.ConstraintDelegate

org.grails.validation.ConstraintsEvaluatorFactoryBean

org.grails.datastore.gorm.validation.constraints.eval.ConstraintsEvaluator

org.grails.validation.CreditCardConstraint

org.grails.datastore.gorm.validation.constraints.CreditCardConstraint

org.grails.validation.DefaultConstraintEvaluator

org.grails.datastore.gorm.validation.constraints.eval.DefaultConstraintEvaluator

org.grails.validation.DomainClassPropertyComparator

org.grails.validation.EmailConstraint

org.grails.datastore.gorm.validation.constraints.EmailConstraint

org.grails.validation.GrailsDomainClassValidator

grails.gorm.validation.PersistentEntityValidator

org.grails.validation.InListConstraint

org.grails.datastore.gorm.validation.constraints.InListConstraint

org.grails.validation.MatchesConstraint

org.grails.datastore.gorm.validation.constraints.MatchesConstraint

org.grails.validation.MaxConstraint

org.grails.datastore.gorm.validation.constraints.MaxConstraint

org.grails.validation.MaxSizeConstraint

org.grails.datastore.gorm.validation.constraints.MaxSizeConstraint

org.grails.validation.MinConstraint

org.grails.datastore.gorm.validation.constraints.MinConstraint

org.grails.validation.MinSizeConstraint

org.grails.datastore.gorm.validation.constraints.MinSizeConstraint

org.grails.validation.NotEqualConstraint

org.grails.datastore.gorm.validation.constraints.NotEqualConstraint

org.grails.validation.NullableConstraint

org.grails.datastore.gorm.validation.constraints.NullableConstraint

org.grails.validation.RangeConstraint

org.grails.datastore.gorm.validation.constraints.RangeConstraint

org.grails.validation.ScaleConstraint

org.grails.datastore.gorm.validation.constraints.ScaleConstraint

org.grails.validation.SizeConstraint

org.grails.datastore.gorm.validation.constraints.SizeConstraint

org.grails.validation.UrlConstraint

org.grails.datastore.gorm.validation.constraints.UrlConstraint

org.grails.validation.ValidatorConstraint

org.grails.datastore.gorm.validation.constraints.ValidatorConstraint

org.grails.validation.routines.DomainValidator