A Gradle plugin that provides Maven-like dependency management and exclusions
Introduction
Based on the configured dependency management metadata, the Dependency Management Plugin will control the versions of your project’s direct and transitive dependencies and will honour any exclusions declared in the poms of your project’s dependencies.
Requirements
The Plugin has the following requirements:
-
Gradle 2.x (2.9 or later), 3.x, or 4.x. Gradle 2.8 and earlier are not supported.
-
Java 6 or later
Getting Started
The plugin is available in the Gradle Plugin Portal and can be applied like this:
plugins {
id "io.spring.dependency-management" version <<version>>
}
plugins {
id("io.spring.dependency-management") version <<version>>
}
If you prefer, the plugin is also available from Maven Central and JCenter.
Snapshots are available from https://repo.spring.io/plugins-snapshot and can be used as shown in the following example:
buildscript {
repositories {
maven { url 'https://repo.spring.io/plugins-snapshot' }
}
dependencies {
classpath 'io.spring.gradle:dependency-management-plugin:<<snapshot-version>>'
}
}
apply plugin: "io.spring.dependency-management"
buildscript {
repositories {
maven {
url = uri("https://repo.spring.io/plugins-snapshot")
}
}
dependencies {
classpath("io.spring.gradle:dependency-management-plugin:<<snapshot-version>>")
}
}
apply(plugin = "io.spring.dependency-management")
With this basic configuration in place, you’re ready to configure the project’s dependency management and declare its dependencies.
Dependency Management Configuration
You have two options for configuring the plugin’s dependency management:
-
Use the plugin’s DSL to configure dependency management directly
-
Import one or more existing Maven boms.
Dependency management can be applied to every configuration (the default) or to one or more specific configurations.
Dependency Management DSL
The DSL allows you to declare dependency management using a :
separated string
to configure the coordinates of the managed dependency, as shown in the following example:
dependencyManagement {
dependencies {
dependency 'org.springframework:spring-core:4.0.3.RELEASE'
}
}
dependencyManagement {
dependencies {
dependency("org.springframework:spring-core:4.0.3.RELEASE")
}
}
Alternatively, you can use a map with group
, name
, and version
entries, as shown
in the following example:
dependencyManagement {
dependencies {
dependency group:'org.springframework', name:'spring-core', version:'4.0.3.RELEASE'
}
}
dependencyManagement {
dependencies {
dependency("org.springframework:spring-core:4.0.3.RELEASE")
dependency(mapOf(
"group" to "org.springframework",
"name" to "spring-core",
"version" to "4.0.3.RELEASE"
))
}
}
With either syntax, this configuration will cause all dependencies (direct or transitive)
on spring-core
to have the version 4.0.3.RELEASE
. When dependency management is in
place, you can declare a dependency without a version, as shown in the following example:
dependencies {
implementation 'org.springframework:spring-core'
}
dependencies {
implementation("org.springframework:spring-core")
}
Dependency Sets
When you want to provide dependency management for multiple modules with the same group and version you should use a dependency set. Using a dependency set removes the need to specify the same group and version multiple times, as shown in the following example:
dependencyManagement {
dependencies {
dependencySet(group:'org.slf4j', version: '1.7.7') {
entry 'slf4j-api'
entry 'slf4j-simple'
}
}
}
dependencyManagement {
dependencies {
dependencySet("org.slf4j:1.7.7") {
entry("slf4j-api")
entry("slf4j-simple")
}
}
}
Exclusions
You can also use the DSL to declare exclusions. The two main advantages of using this mechanism
are that they will be included in the <dependencyManagement>
of your project’s
generated pom and that they will be applied using Maven’s exclusion semantics.
An exclusion can be declared on individual dependencies, as shown in the following example:
dependencyManagement {
dependencies {
dependency('org.springframework:spring-core:4.0.3.RELEASE') {
exclude 'commons-logging:commons-logging'
}
}
}
dependencyManagement {
dependencies {
dependency("org.springframework:spring-core:4.0.3.RELEASE") {
exclude("commons-logging:commons-logging")
}
}
}
An exclusion can also be declared on an entry in a dependency set, as shown in the following example:
dependencyManagement {
dependencies {
dependencySet(group:'org.springframework', version: '4.1.4.RELEASE') {
entry('spring-core') {
exclude group: 'commons-logging', name: 'commons-logging'
}
}
}
}
dependencyManagement {
dependencies {
dependencySet("org.springframework:4.1.4.RELEASE") {
entry("spring-core") {
exclude(mapOf("group" to "commons-logging", "name" to "commons-logging"))
}
}
}
}
As shown in the two examples above, an exclusion can be identified using a string in the
form 'group:name'
or a map with group
and name
entries.
Gradle does not provide an API for accessing a dependency’s classifier during resolution. Unfortunately, this means that dependency management-based exclusions will not work when a classifier is involved. |
Importing a Maven Bom
The plugin also allows you to import an existing Maven bom to utilise its dependency management, as shown in the following example:
dependencyManagement {
imports {
mavenBom 'io.spring.platform:platform-bom:1.0.1.RELEASE'
}
}
dependencies {
implementation 'org.springframework.integration:spring-integration-core'
}
dependencyManagement {
imports {
mavenBom("io.spring.platform:platform-bom:1.0.1.RELEASE")
}
}
dependencies {
implementation("org.springframework.integration:spring-integration-core")
}
This configuration will apply the versions in the Spring IO Platform bom to the project’s dependencies:
$ gradle dependencies --configuration compileClasspath
> Task :dependencies
------------------------------------------------------------
Root project
------------------------------------------------------------
compileClasspath - Compile classpath for source set 'main'.
\--- org.springframework.integration:spring-integration-core -> 4.0.2.RELEASE
+--- org.springframework.retry:spring-retry:1.1.0.RELEASE
| \--- org.springframework:spring-context:4.0.3.RELEASE -> 4.0.6.RELEASE
| +--- org.springframework:spring-aop:4.0.6.RELEASE
| | +--- aopalliance:aopalliance:1.0
| | +--- org.springframework:spring-beans:4.0.6.RELEASE
| | | \--- org.springframework:spring-core:4.0.6.RELEASE
| | \--- org.springframework:spring-core:4.0.6.RELEASE
| +--- org.springframework:spring-beans:4.0.6.RELEASE (*)
| +--- org.springframework:spring-core:4.0.6.RELEASE
| \--- org.springframework:spring-expression:4.0.6.RELEASE
| \--- org.springframework:spring-core:4.0.6.RELEASE
+--- org.springframework:spring-tx:4.0.5.RELEASE -> 4.0.6.RELEASE
| +--- org.springframework:spring-beans:4.0.6.RELEASE (*)
| \--- org.springframework:spring-core:4.0.6.RELEASE
+--- org.springframework:spring-messaging:4.0.5.RELEASE -> 4.0.6.RELEASE
| +--- org.springframework:spring-beans:4.0.6.RELEASE (*)
| +--- org.springframework:spring-context:4.0.6.RELEASE (*)
| \--- org.springframework:spring-core:4.0.6.RELEASE
+--- org.springframework:spring-context:4.0.5.RELEASE -> 4.0.6.RELEASE (*)
\--- org.springframework:spring-aop:4.0.5.RELEASE -> 4.0.6.RELEASE (*)
It’s provided a version of 4.0.2.RELEASE
for the spring-integration-core
dependency.
It has also set the version of all of the Spring Framework dependencies to 4.0.6.RELEASE
Importing Multiple Boms
If you import more than one bom, the order in which the boms are imported can be important. The boms are processed in the order in which they are imported. If multiple boms provide dependency management for the same dependency, the dependency management from the last bom will be used.
Overriding Versions in a Bom
If you want to deviate slightly from the dependency management provided by a bom, it can be useful to be able to override a particular managed version. There are two ways to do this:
-
Change the value of a version property
-
Override the dependency management
Changing the Value of a Version Property
If the bom has been written to use properties for its versions then you can override the version by providing a different value for the relevant version property.
You should only use this approach if you do not intend to generate and publish a Maven pom for your project as it will result in a pom that does not override the version. |
Building on the example above, the Spring IO Platform bom that is used contains a property
named spring.version
. This property determines the version of all of the Spring
Framework modules and, by default, its value is 4.0.6.RELEASE
.
A property can be overridden as part of importing a bom, as shown in the following example:
dependencyManagement {
imports {
mavenBom('io.spring.platform:platform-bom:1.0.1.RELEASE') {
bomProperty 'spring.version', '4.0.4.RELEASE'
}
}
}
dependencyManagement {
imports {
mavenBom("io.spring.platform:platform-bom:1.0.1.RELEASE") {
bomProperty("spring.version", "4.0.4.RELEASE")
}
}
}
You can also use a map, as shown in the following example:
dependencyManagement {
imports {
mavenBom('io.spring.platform:platform-bom:1.0.1.RELEASE') {
bomProperties([
'spring.version': '4.0.4.RELEASE'
])
}
}
}
dependencyManagement {
imports {
mavenBom("io.spring.platform:platform-bom:1.0.1.RELEASE") {
bomProperties(mapOf(
"spring.version" to "4.0.4.RELEASE"
))
}
}
}
Alternatively, the property can also be overridden using a project’s properties configured
via any of the mechanisms that Gradle provides. You may choose to configure
it in your build.gradle
script, as shown in the following example:
ext['spring.version'] = '4.0.4.RELEASE'
ext["spring.version"] = "4.0.4.RELEASE"
Or in gradle.properties
spring.version=4.0.4.RELEASE
Wherever you configure it, the version of any Spring Framework modules will now match the value of the property:
$ gradle dependencies --configuration compileClasspath
> Task :dependencies
------------------------------------------------------------
Root project
------------------------------------------------------------
compileClasspath - Compile classpath for source set 'main'.
\--- org.springframework.integration:spring-integration-core -> 4.0.2.RELEASE
+--- org.springframework.retry:spring-retry:1.1.0.RELEASE
| \--- org.springframework:spring-context:4.0.3.RELEASE -> 4.0.4.RELEASE
| +--- org.springframework:spring-aop:4.0.4.RELEASE
| | +--- aopalliance:aopalliance:1.0
| | +--- org.springframework:spring-beans:4.0.4.RELEASE
| | | \--- org.springframework:spring-core:4.0.4.RELEASE
| | \--- org.springframework:spring-core:4.0.4.RELEASE
| +--- org.springframework:spring-beans:4.0.4.RELEASE (*)
| +--- org.springframework:spring-core:4.0.4.RELEASE
| \--- org.springframework:spring-expression:4.0.4.RELEASE
| \--- org.springframework:spring-core:4.0.4.RELEASE
+--- org.springframework:spring-tx:4.0.5.RELEASE -> 4.0.4.RELEASE
| +--- org.springframework:spring-beans:4.0.4.RELEASE (*)
| \--- org.springframework:spring-core:4.0.4.RELEASE
+--- org.springframework:spring-messaging:4.0.5.RELEASE -> 4.0.4.RELEASE
| +--- org.springframework:spring-beans:4.0.4.RELEASE (*)
| +--- org.springframework:spring-context:4.0.4.RELEASE (*)
| \--- org.springframework:spring-core:4.0.4.RELEASE
+--- org.springframework:spring-context:4.0.5.RELEASE -> 4.0.4.RELEASE (*)
\--- org.springframework:spring-aop:4.0.5.RELEASE -> 4.0.4.RELEASE (*)
Overriding the Dependency Management
If the bom that you have imported does not use properties, or you want the override to be honoured in the Maven pom that’s generated for your Gradle project, you should use dependency management to perform the override. For example, if you’re using the Spring IO Platform bom, you can override its version of Guava and have that override apply to the generated pom, as shown in the following example:
dependencyManagement {
imports {
mavenBom 'io.spring.platform:platform-bom:1.1.1.RELEASE'
}
dependencies {
dependency 'com.google.guava:guava:18.0'
}
}
dependencyManagement {
imports {
mavenBom("io.spring.platform:platform-bom:1.1.1.RELEASE")
}
dependencies {
dependency("com.google.guava:guava:18.0")
}
}
This will produce the following <dependencyManagement>
in the generated pom file:
<dependencyManagement>
<dependencies>
<dependency>
<groupId>io.spring.platform</groupId>
<artifactId>platform-bom</artifactId>
<version>1.1.1.RELEASE</version>
<scope>import</scope>
<type>pom</type>
</dependency>
<dependency>
<groupId>com.google.guava</groupId>
<artifactId>guava</artifactId>
<version>18.0</version>
</dependency>
</dependencies>
</dependencyManagement>
The dependency management for Guava that’s declared directly in the pom takes precedence
over any dependency management for Guava in the platform-bom
that’s been imported.
You can also override the dependency management by declaring a dependency and configuring it with the desired version, as shown in the following example:
dependencies {
implementation("com.google.guava:guava:18.0")
}
This will cause any dependency (direct or transitive) on com.google.guava:guava:18.0
in
the implementation
configuration to use version 18.0
, overriding any dependency management
that may exist. If you do not want a project’s dependencies to override its dependency
management, this behavior can be disabled using overriddenByDependencies
, as shown in
the following example:
dependencyManagement {
overriddenByDependencies = false
}
dependencyManagement {
overriddenByDependencies(false)
}
Configuring the Dependency Management Resolution Strategy
The plugin uses separate, detached configurations for its internal dependency resolution. You can configure the resolution strategy for these configurations using a closure. If you’re using a snapshot, you may want to disable the caching of an imported bom by configuring Gradle to cache changing modules for zero seconds, as shown in the following example:
dependencyManagement {
resolutionStrategy {
cacheChangingModulesFor 0, 'seconds'
}
}
dependencyManagement {
resolutionStrategy {
cacheChangingModulesFor(0, TimeUnit.SECONDS)
}
}
Dependency Management for Specific Configurations
To target dependency management at a single configuration, you nest the dependency
management within a block named after the configuration, such as implementation
as shown
in the following example:
dependencyManagement {
implementation {
dependencies {
// …
}
imports {
// …
}
}
}
To target dependency management at multiple configurations, you use configurations
to
list the configurations to which the dependency management should be applied, as shown in
the following example:
dependencyManagement {
configurations(implementation, custom) {
dependencies {
…
}
imports {
…
}
}
}
dependencyManagement {
configurations {
listOf("implementation", "custom").forEach {configName ->
getByName(configName) {
dependencies {
…
}
imports {
…
}
}
}
}
}
Accessing Properties from Imported Boms
The plugin makes all of the properties from imported boms available for use in your Gradle
build. Properties from both global dependency management and configuration-specific
dependency management can be accessed. A property named spring.version
from global
dependency management can be accessed as shown in the following example:
dependencyManagement.importedProperties['spring.version']
dependencyManagement.importedProperties["spring.version"]
The same property from the implementation configuration’s dependency management can be accessed as shown in the following example:
dependencyManagement.implementation.importedProperties['spring.version']
Accessing imported properties for a specific configuration is not currently supported when using the Kotlin DSL. |
Maven Exclusions
While Gradle can consume dependencies described with a Maven pom file, Gradle does not honour Maven’s semantics when it is using the pom to build the dependency graph. A notable difference that results from this is in how exclusions are handled. This is best illustrated with an example.
Consider a Maven artifact, exclusion-example
, that declares a dependency on
org.springframework:spring-core
in its pom with an exclusion for
commons-logging:commons-logging
, as illustrated in the following example:
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>4.1.3.RELEASE</version>
<exclusions>
<exclusion>
<groupId>commons-logging</groupId>
<artifactId>commons-logging</artifactId>
</exclusion>
</exclusions>
</dependency>
If we have a Maven project, consumer
, that depends on
exclusion-example
and org.springframework:spring-beans
the exclusion in
exlusion-example
prevents a transitive dependency on commons-logging:commons-logging
.
This can be seen in the following output from mvn dependency:tree
:
+- com.example:exclusion-example:jar:1.0:compile
| \- org.springframework:spring-core:jar:4.1.3.RELEASE:compile
\- org.springframework:spring-beans:jar:4.1.3.RELEASE:compile
If we create a similar project in Gradle the dependencies are different as the exclusion
of commons-logging:commons-logging
is not honored. This can be seen in the following output
from gradle dependencies
:
+--- com.example:exclusion-example:1.0
| \--- org.springframework:spring-core:4.1.3.RELEASE
| \--- commons-logging:commons-logging:1.2
\--- org.springframework:spring-beans:4.1.3.RELEASE
\--- org.springframework:spring-core:4.1.3.RELEASE (*)
Despite exclusion-example
excluding commons-logging
from its spring-core
dependency,
spring-core
has still pulled in commons-logging
.
The dependency management plugin improves Gradle’s handling of exclusions that have been declared in a Maven pom by honoring Maven’s semantics for those exclusions. This applies to exclusions declared in a project’s dependencies that have a Maven pom and exclusions declared in imported Maven boms.
Disabling Maven exclusions
The plugin’s support for applying Maven’s exclusion semantics can be disabled by setting
applyMavenExclusions
to false, as shown in the following example:
dependencyManagement {
applyMavenExclusions = false
}
dependencyManagement {
applyMavenExclusions(false)
}
Pom generation
Gradle’s maven
and maven-publish
plugins automatically generate a pom file that
describes the published artifact. The plugin will automatically include any global
dependency management, i.e. dependency management that does not target a specific
configuration, in the <dependencyManagement>
section of the generated pom file. For
example, the following dependency management configuration:
dependencyManagement {
imports {
mavenBom 'com.example:bom:1.0'
}
dependencies {
dependency 'com.example:dependency:1.5'
}
}
dependencyManagement {
imports {
mavenBom("com.example:bom:1.0")
}
dependencies {
dependency("com.example:dependency:1.5")
}
}
Will result in the following <dependencyManagement>
in the generated pom file:
<dependencyManagement>
<dependencies>
<dependency>
<groupId>com.example</groupId>
<artifactId>bom</artifactId>
<version>1.0</version>
<scope>import</scope>
<type>pom</type>
<dependency>
<dependency>
<groupId>com.example</groupId>
<artifactId>dependency</artifactId>
<version>1.5</version>
</dependency>
<dependencies>
</dependencyManagement>
Disabling the customization of a generated pom
If you prefer to have complete control over your project’s generated pom, you can disable
the plugin’s customization by setting enabled
to false, as shown in the following
example:
dependencyManagement {
generatedPomCustomization {
enabled = false
}
}
dependencyManagement {
generatedPomCustomization {
enabled(false)
}
}
Working with the Managed Versions
Dependency Management Task
The plugin provides a task, dependencyManagement
, that will output a report of the
project’s dependency management, as shown in the following example:
$ gradle dependencyManagement
> Task :dependencyManagement
------------------------------------------------------------
Root project
------------------------------------------------------------
global - Default dependency management for all configurations
org.springframework:spring-core 4.1.5.RELEASE
annotationProcessor - Dependency management for the annotationProcessor configuration
No configuration-specific dependency management
apiElements - Dependency management for the apiElements configuration
No configuration-specific dependency management
archives - Dependency management for the archives configuration
No configuration-specific dependency management
compile - Dependency management for the compile configuration
No configuration-specific dependency management
compileClasspath - Dependency management for the compileClasspath configuration
No configuration-specific dependency management
compileOnly - Dependency management for the compileOnly configuration
No configuration-specific dependency management
default - Dependency management for the default configuration
No configuration-specific dependency management
implementation - Dependency management for the implementation configuration
No configuration-specific dependency management
runtime - Dependency management for the runtime configuration
No configuration-specific dependency management
runtimeClasspath - Dependency management for the runtimeClasspath configuration
No configuration-specific dependency management
runtimeElements - Dependency management for the runtimeElements configuration
No configuration-specific dependency management
runtimeOnly - Dependency management for the runtimeOnly configuration
No configuration-specific dependency management
testAnnotationProcessor - Dependency management for the testAnnotationProcessor configuration
No configuration-specific dependency management
testCompile - Dependency management for the testCompile configuration
No configuration-specific dependency management
testCompileClasspath - Dependency management for the testCompileClasspath configuration
org.springframework:spring-beans 4.1.5.RELEASE
org.springframework:spring-core 4.1.5.RELEASE
testCompileOnly - Dependency management for the testCompileOnly configuration
No configuration-specific dependency management
testImplementation - Dependency management for the testImplementation configuration
org.springframework:spring-beans 4.1.5.RELEASE
org.springframework:spring-core 4.1.5.RELEASE
testRuntime - Dependency management for the testRuntime configuration
No configuration-specific dependency management
testRuntimeClasspath - Dependency management for the testRuntimeClasspath configuration
org.springframework:spring-beans 4.1.5.RELEASE
org.springframework:spring-core 4.1.5.RELEASE
testRuntimeOnly - Dependency management for the testRuntimeOnly configuration
No configuration-specific dependency management
This report is produced by a project with the following dependency management:
dependencyManagement {
dependencies {
dependency 'org.springframework:spring-core:4.1.5.RELEASE'
}
testImplementation {
dependencies {
dependency 'org.springframework:spring-beans:4.1.5.RELEASE'
}
}
}
Programmatic access
The plugin provides an API for accessing the versions provided by the configured
dependency management. The managed versions from global dependency management are
available from dependencyManagement.managedVersions
, as shown in the following example:
def managedVersions = dependencyManagement.managedVersions
val managedVersions = dependencyManagement.managedVersions
Managed versions from configuration-specific dependency management are available from
dependencyManagement.<configuration>.managedVersions
, as shown in the following
example for the implementation `configuratation
:
def managedVersions = dependencyManagement.implementation.managedVersions
dependencyManagement.getManagedVersionsForConfiguration(configurations.getByName("implementation"))
The managed versions are of map of groupId:artifactId
to version
, as shown in the
following example for accessing the version of org.springframework:spring-core
:
def springCoreVersion = managedVersions['org.springframework:spring-core']
val springCoreVersion = managedVersions["org.springframework:spring-core"]