Talk about Gradle at JEEConf 2018

1. GRADLE
HOW TO’S
Serhii Belei

2. ABOUT ME
• 34 Years old
• Married and have 3 kids
• 7 years work at SoftServe
• Work with Gradle since version 2.9

3. THERE IS NOTHING
MORE DIFFICULT TO TAKE IN HAND,
MORE PERILOUS TO CONDUCT,
OR MORE UNCERTAIN IN ITS SUCCESS,
THAN TO REPLACE ANY EXISTING BUILD
SYSTEM WITH GRADLE.
NICCOLO MACHIAVELLI*

4. WHY GRADLE

5. AGENDA
1) Configuration of Eclipse project
2) Jenkins job configuration
3) Release process with gradle-release plugin
4) Rest of how to’s

6. BUILD.GRADLE IS SINGLE POINT OF
TRUTH
build.gradle
jar IDE CI
quality release

8. ECLIPSE PROJECT FROM BUILD IN A
PERFECT WORLD
apply plugin: 'eclipse'

9. CONFIGURATION OF ECLIPSE PROJECT
FROM BUILD
1. Applying some Eclipse specific settings
2. Understanding configuration tweaking in .project
3. Work with .classpath

10. SOURCE/TARGET COMPATIBILITY
sourceCompatibility = 1.7
targetCompatibility = 1.8

11. .SETTINGS/ORG.ECLIPSE.JDT.CORE.PREFS
eclipse.preferences.version=1
...
org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.8
org.eclipse.jdt.core.compiler.compliance=1.7
org.eclipse.jdt.core.compiler.source=1.7
...

12. eclipse { jdt { file {
withProperties { properties ->
properties.setProperty(
"org.eclipse.jdt.core.compiler.compliance", "1.8")
}
}}}

13. LINKED EXTERNAL FOLDER EXAMPLE

14. .PROJECT DSL
eclipse { project {
linkedResource(
name: "res_name",
type: '2',
location: "C:/res_path/src")
}}

15. .PROJECT
<?xml version="1.0" encoding="UTF-8"?>
<projectDescription>
...
<linkedResources>
<link>
<name>res_name</name>
<type>2</type>
<location>C:/res_path/src</location>
</link>

16. .CLASSPATH DSL
classpath { file { withXml {
def node = it.asNode()
node.appendNode('classpathentry',
[kind: 'src', path: "C:res_pathsrc"])
node.appendNode('classpathentry',
[kind: 'con', path: "... Tomcat8.5"])

17. .CLASSPATH
<?xml version="1.0" encoding="UTF-8"?>
<classpath>
...
<classpathentry kind="src" path="C:/res_path/src"/>
<classpathentry kind="con" path="... Tomcat8.5"/>
...

18. NO TESTS IN TOMCAT
classpath { file { whenMerged { cp ->
cp.entries.findAll {
it instanceof SourceFolder &&
(it.path.startsWith("test") ||
it.path.endsWith("test"))
}*.output = "test-bin"
}}}

19. .CLASSPATH
<?xml version="1.0" encoding="UTF-8"?>
<classpath>
...
<classpathentry kind="src" path="src"/>
<classpathentry output="test-bin"
kind="src" path="test"/>

20. JENKINS JOB FROM BUILD
1. Old Jenkins DSL
2. No support Jenkins CSRF protection mechanism
3. No support for Jenkins job "Folders”

21. JENKINS GRADLE PLUGIN - FAIRY TALE

22. GRADLE-JENKINS PLUGIN USED OLD
DSL
dsl {
configure { project ->
permission("hudson.model.Run.Delete:${user_id}")

27. HOW TO PUBLISH PLUGIN ON
PLUGINS.GRADLE.COM
• Register and get API key
• Store it in %USER_HOME%/.gradle/gradle.properties
• Publish and wait for approval of gradle team
gradle.publish.key=****
gradle.publish.secret=****

28. PITFALL DURING PUBLISH TO
PLUGINS.GRADLE.ORG
There was a bug in the plugin-publish plugin in versions prior to 0.9.7
(https://discuss.gradle.org/t/plugin-authors-please-use-the-latest-plugin-
publish-plugin-others-may-result-in-a-broken-upload/23573 ), where
artifacts would silently not be pushed into the repo, which means the
latest version of your plugin will not work properly when people apply it to
their build.
Upgrading to the latest version of the plugin-publish-plugin will fix this, but
this will require pushing a new version of your plugin.

29. HOW TO PUBLISH PLUGIN ON
PLUGINS.GRADLE.COM IMPROVED
• Register and get API key
• Store it in %USER_HOME%/.gradle/gradle.properties
• For old plugin, check publisher version
'com.gradle.publish:plugin-publish-plugin:0.9.9'
• Publish and wait for approval of gradle team
• Contact support if something went wrong !!!

30. LESSONS LEARNED
Source code you may find here:
https://github.com/crc83/gradle-jenkins-
plugin
1) Be ready to maintain any plugin you’re
using in your build
2) Ask for support as soon as possible

31. RELEASE PROCESS CONFIGURATION
WITH GRADLE-RELEASE PLUGIN
https://jug.ru/2017/04/maven-sdkman/

32. RELEASE PROCESS CONFIGURATION
WITH GRADLE-RELEASE PLUGIN
release {
tagTemplate='$name-$version'
buildTasks = ['jar', 'test']
}

33. PITFALL
https://github.com/researchgate/gradle-
release/blame/master/src/main/groovy/net/researchgate/release/ReleasePl
ugin.groovy#L118

34. SOLUTION
release {
buildTasks = ['dailyBuild']
}
task dailyBuild(type: GradleBuild) {
tasks = ['jar', 'test']
}

35. RELEASE IN PIPELINE JOB
1) Store dependency versions in gradle.properties
2) Create a task that updates gradle.properties to values
passed as parameter
project _a
version 0.0.1-SNAPSHOT
project_b
version 0.0.2-SNAPSHOT
dependency
project _a :0.0.1-SNAPSHOT
project_c
version 0.0.3-SNAPSHOT
dependency
project_b:0.0.2-SNAPSHOT

36. DEPENDENCY TO PROJECT_A
<build.gradle>
dependencies {
compile 'project_a:0.0.1-SNAPSHOT‘

37. VERSION EXTRACTED TO PROPERTY
<build.gradle>
dependencies {
compile "project_a:${project_a_version}“
<gradle.properties>
project_a_version=0.0.1-SNAPSHOT

38. TASK TO UPDATE PROPERTIES
task updateProps() {
writeVersion(file('gradle.properties'),
'project_a_version','1.0.0')
}

39. protected void writeVersion(File file, String key, version) {
if (!file.file) {
project.ant.echo(file: file, message: "$key=$version")
} else {
project.ant.replaceregexp(file: file, byline: true) {
regexp(pattern:
"^(s*)$key((s*[=|:]s*)|(s+)).+$")
substitution(expression: "1$key2$version")}
}}

40. RELEASE IN PIPELINE JOB
Project A
version A.0.1
Project B
version B.0.2-SNAPSHOT
dependency A:A.0.1-SNAPSHOT
Project C
version C.0.3-SNAPSHOT
dependency B:0.2-SNAPSHOT
gradle.properties
dependency A:A.0.1

41. RELEASE IN PIPELINE JOB
Two steps approach
1)Update dependency versions and check them
into SCM
2)Do a release

42. UNSORTED
1. How to store credentials and other secured information not in
the script (locally and on Jenkins)
2. Common rules how we moved build logic to plugin
3. How to apply plugin for itself

43. HOW TO STORE SECURED
INFORMATION

44. HOW TO STORE SECURED
INFORMATION

45. HOW TO STORE SECURED
INFORMATION

46. USE PLACEHOLDER IN SCRIPT
jenkins { servers {
local {
url 'http://localhost:9090'
secure true
username "$some_user"
password "$some_password"

47. SECURED INFORMATION : LOCALLY
Store values in
%USER_HOME%/.gradle/gradle.properties

48. SECURED INFORMATION : ON JENKINS

49. COMMON RULES HOW WE MOVED
BUILD LOGIC TO PLUGIN
1) Use project object
2) Separate task definition and definition of task logic
3) Define your extension with default values
4) Access values on 3rd party extensions in afterEvaluate phase
5) Use --include-build=path/to/project/with/plugin to
test your plugin on real project

50. apply plugin: 'org.sonarqube'
sonarqube{
properties {
...
property "sonar.java.coveragePlugin", "cobertura"
property "sonar.cobertura.reportPath",
file("$buildDir/reports/cobertura/coverage.xml")
}
}

51. @Override
void apply(Project project) {
...
project.apply plugin:
org.sonarqube.gradle.SonarQubePlugin
project.afterEvaluate {
...
}
}

52. project.sonarqube {
properties {
….
property "sonar.java.coveragePlugin", "cobertura"
property "sonar.cobertura.reportPath",
project.file("$buildDir/reports/cobertura/coverage.xml
")
}
}

53. HOW TO WRITE OWN GRADLE PLUGIN
AND TEST IT
https://crc83.blogspot.com/2016/03/i-
getting-started-with-environment.html

54. ADD BUILD.GRADLE TO buildSrc FOLDER
apply plugin: "java"
apply plugin: "groovy“
repositories {...}
dependencies {...}
sourceSets {TBD}

55. sourceSets { main {
java {srcDir '../src/main/java'}
groovy {srcDir '../src/main/groovy'}
resources {srcDir '../src/main/resources'}
}}

56. OVERALL LESSONS LEARNED
1) Whatever you’re going to do with Gradle is tricky
2) Whatever you’re going to do with Gradle is possible
3) Make your script as much declarative as possible

58. THANK
YOU