Detect unused and misused dependencies

The Dependency Analysis Gradle Plugin (DAGP, née Dependency Analysis Android Gradle Plugin) detects the following:

1. Unused dependencies.

2. Used transitive dependencies (which you may want to declare directly).

3. Dependencies declared on the wrong configuration (api vs implementation vs compileOnly, etc.).

As a side effect, the plugin can also tell you your project’s ABI, and produces graphviz files representing various views of your dependency graph, among other things. These side effects are currently mostly undocumented internal behaviors, but they may be interesting for some advanced users.

Build health

In addition to the dependency-related advice (see above), DAGP provides other advice to help maintain your "build health." This includes the detection of:

1. Unnecessary plugins (currently only kapt).

2. Subprojects ("modules") that unnecessarily use the Android plugin, and could instead by "normal" JVM libraries.

Compatibilities

Please see the wiki for information on the versions of Gradle, the Android Gradle Plugin, etc., that this plugin is compatible with.

Add to your project and use

For detailed instructions, see the wiki.

The simplest approach is to add the following:

root build.gradle

plugins {
  id("com.autonomousapps.dependency-analysis") version "<<latest_version>>"
}

For a quick start, just run the following:

./gradlew buildHealth

You will probably see output like the following:

> Task :buildHealth FAILED

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':buildHealth'.
> There were dependency violations. See report at file:///path/to/project/build/reports/dependency-analysis/build-health-report.txt

If you wish to have this (potentially very long) report printed to console, add this to your gradle.properties file:

gradle.properties

dependency.analysis.print.build.health=true

More advanced usage

Project Health

You can also run the analysis against individual modules with the projectHealth task. For example:

./gradlew app:projectHealth

Reason

You may be curious why the plugin is emitting (or not emitting) advice regarding some dependency. You can ask it why:

./gradlew lib:reason --id com.squareup.okio:okio:2.2.2 (1)
> Task :lib:reason

----------------------------------------
You asked about the dependency 'com.squareup.okio:okio:2.2.2'.
There is no advice regarding this dependency.
----------------------------------------

Shortest path from :lib to com.squareup.okio:okio:2.2.2:
:lib
\--- com.squareup.okio:okio:2.2.2

Source: main
------------
* Exposes class okio.BufferedSource (implies api).

1. The version string is optional.

Basic configuration

For detailed information on how to configure the plugin, see the wiki.

To configure the plugin, use the dependencyAnalysis extension.

build.gradle

dependencyAnalysis {
  // configuration goes here
}

Publications

The following is a list of articles / blog posts that have been published discussing this plugin:

1. The proper care and feeding of your Gradle build

2. Dependency Analysis Gradle Plugin: Using bytecode analysis to find unused dependencies

3. Dependency Analysis Gradle Plugin: What’s an ABI?

4. Reducing my Gradle plugin’s impact on configuration time: A journey

…​with more to come :)

This plugin has also been featured in these newsletters:

1. Gradle, May 2022

2. Gradle, September 2020

3. Gradle, August 2020

4. Android Weekly, Issue #423

5. Gradle, July 2020

6. Gradle, June 2020

Podcast episodes about this plugin could be found here:

1. The Developers' Bakery, Episode #31

Youtube videos about this plugin:

1. Understanding Gradle #28 – Clean Compile Classpaths with the Dependency Analysis Plugin