Gradle Fundamentals
Ant
XML build Script:
- hard to read
- difficult to maintain
Maven
- many conventions
- highly extendable
- hard to read
- could be difficult to maintain
Gradle Build
- Gradle has build file
- Typically build.gradle
- This contains tasks (task based)
- plugins
- dependencies
- mostly tasks
ex:
build.gradle
task hello {
doLast {
println “Hello, Gradle”
}
}Introduction to the Gradle Wrapper
e.g.
task wrapper (type: Wrapper) {
gradleVersion = ‘2.6’
}Now can run gradlew build
- download the gradle
- then build
Writing Simple Tasks
Task:
- code that grade executes
- has a lifecycle
- has properties
- has ‘actions’ (code to be execute)
- has dependencies
E.g. (in groovy)
project.task(“Task1”)- project is the top level object
task(“Task2”)
task “Task3”
task Task4
Task4.description = “Task 4 Description”Running a Task
— gradle Task4
e.g.
Task4.doLast {
println “This is task 4”
}
——————————————————————
Task3 << {println “This is task 3”}
——————————————————————
Task task 5 << {println “this is task 5”}
task5 << {println “Another closure“} // if we save this and when we run gradle build, could replace the first one, or append to the last one
——————————————————————
// some execution phases
task task6 {
description “this is task 6“
doLast {
println “this is task 6”
}
}Build Phases
- initialisation phases: used to configure multi projects builds
- Configuration Phase: executes code in the task that’s not the action e.g. .. description “some thing”…
- Excution Phase: doLast, doFirst
Task Dependencies
e.g.
Task6.dependsOn Task5 // when we run task6, we will see Task5 run first.Setting properties on Tasks
e.g.
def projectVersion = “2.0” // local variable, only available to the build.gradle
project.ext.projectVersion = “2.0” // global variable to all the projects
// or
ext.projectVersion = “2.0”Task Dependencies
- understand how tasks can be linked
Using mustRunAfter and shouldRunAfter
- mustRunAfter
- if two tasks execute on must run after the other
- shouldRUnAfter
- if two tasks execute one should run after the other
- this ignores circular dependencies
- finalised by (incubating in 2.6)
- inverted dependency
Introduction to Typed Tasks
- suppose we want something more complex
- can be reuse the task code
- e.g. copying files
- Open file/ read file/ write file
- e.g. Zipping files
- would like this to be reused
Using the Copy task
copying some images:
e.g.
def contentSpec = cpySpec {
exclude ‘IMG_—52.jpg’
from ‘src’
}
task copyImages2 (type: Copy) {
// with contentSpec
exclude { it.file.name.startWith(‘IMG’) } // write groovy code to configure the task
into ‘dest’
}
task copyImages (type: Copy) {
exclude ‘IMG_0052.jpg’
from ‘src’
into ‘dest’
}
task copyConfig (type: Copy) {
include ‘web.xml’
from ‘src’
into ‘config’
expand {
[resourceRefName: ‘hsbc 1.0’]
}
}integral to Java Plugin
Defines:
- a source set
- task to compile the test
- task to run the test
Source Set
- Looks for unit tests in src/test/java
- Outputs to build/classes/test
- Reports to build/reports/test
Filtering
- Can filter to only run a subset of tests
- Single test
- All tests from a package
- Wildcard is supported e.g.
test {
filter {
includeTestsMatching “com.foo.shouldCreateASession”
includeTestsMatching “*shouldCreateASession”
}
}Other Testing
- Integration tests for example
- add the cradle-testsets-plugin
- add a testSet
- set other configurations parameters
- set output reports directory
buildscript:
- add dependencies for build script not for tasks
allprojects:
- apply all the content to all the projects when built
Wrapper
- provides a specific version of Gradle to the project
- get consistent builds
- gradlew.bat on Windows
- cradle shell script on *unix
- Standard task
- always available
e.g.
task wrapper(type: Wrapper) {
gradleVersion = ‘2.6’
}Running the Wrapper
- run the specific gradle
- if not installed will download and install specific gradle
