Current Status
I am no longer involved in development, so am not able to maintain or provide bug fixes or even test the pull requests. It would be great if someone who actually is using this project in their library and can actively maintain the repo, become part of/take it over.
Meanwhile, you can also check fat-aar-plugin which is trying to solve the same problem using a plugin.
android-fat-aar
Gradle script that allows you to merge and embed dependencies in generated aar file.
In this Fork you can find a fixed version who will also work with embedded .aar files !
Credits
jksiezni suggested an alternate way to embed R files which fixes ugly internal proguard hack.
jonbryantnz suggested method to embed java projects.
Why do I need is a fat AAR?
There may be multiple reasons for wanting this. My reason was that I wanted to publish a single library while maintaining a modular structure within the project. The benefit of a fat aar file is that we can proguard the combined code instead of proguarding each and every subproject which is not that effective.
What doesn't work?
- Manifest placeholders that are expected to be filled in by the application
- AIDL File merger - I do not use aidl files
- Multiple build types - only single build type (release) is supported out of the box
- ?
Step 1: Apply the gradle file
To use this simply copy the gradle file 'fat-aar.gradle' to your project directory and then
apply from: 'fat-aar.gradle'
or apply directly from the url
apply from: 'https://raw.githubusercontent.com/adwiv/android-fat-aar/master/fat-aar.gradle'
Step 2: Define the embedded dependencies
Then you can modify the dependencies section and change the word compile
to embedded
for the dependencies you want merged within the aar file. The resulting section may look like this:
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
// Order of dependencies decide which will have precedence in case of duplicates
// during manifest / resource merger
embedded project(':librarytwo')
embedded project(':libraryone')
embedded project('com.example.internal:lib-three:1.2.3')
compile 'com.example:some-other-lib:1.0.3'
compile 'com.android.support:appcompat-v7:22.2.0'
}
The dependencies with keyword embedded
will be merged while the others will remain referenced as before.
Step 3: Remove embedded dependencies from exported dependency list
Now that you have embedded your sub projects into the main library, you need to ensure that anyone using your library does not resolve the embedded projects as transitive dependencies. Otherwise he will get duplicate class errors.
If you are using the fat library within the same project (maybe within a test app?), then you can simply define your fat-library dependency as non transitive.
compile (project(':applibrary')) { // Notice the parentheses around project
transitive false
}
For external clients or use in another project; this can be achieved by removing these dependencies from the generated pom.xml file. How to automate that will depend on how you are generating the pom file. I use maven-publish
plugin with the following pom generator.
pom.withXml {
def dependenciesNode = asNode().appendNode('dependencies')
//Iterate over the compile dependencies (we don't want the test ones), adding a <dependency> node for each
configurations.compile.allDependencies.each {
if(it.group != null && (it.name != null || "unspecified".equals(it.name)) && it.version != null)
{
if(!configurations.embedded.allDependencies.contains(it)) {
def dependencyNode = dependenciesNode.appendNode('dependency')
dependencyNode.appendNode('groupId', it.group)
dependencyNode.appendNode('artifactId', it.name)
dependencyNode.appendNode('version', it.version)
}
}
}
}
The complete publish.gradle
file (That also automatically adds the transitive dependencies as primary) is in the repository.
Hope this helps.