Using api as dependency configuration confused me

[JackEblan]

Why use api in core/data/build.gradle.kts?

If I understood correctly, feature modules can see the dependency of the core:data module like core:network, core:datastore, core:database. I think the interfaces from data layer is what they needed. There should be an explanation to this. Thanks.

[Jaehwa-Noh]

I'm not sure I am fully understand your question.
If you want to know what different between api and implementation, you can see this documentation

[JackEblan]

Hello @Jaehwa-Noh, thanks for the response.

My confusion is that :core:data exposes the :core:model to FEATURE Modules but the code here

nowinandroid/build-logic/convention/src/main/kotlin/AndroidFeatureConventionPlugin.kt

Line 42 in 7980c1d

add("implementation", project(":core:ui"))

already tells that :core:model is already accessible because

nowinandroid/core/ui/build.gradle.kts

Line 33 in 7980c1d

api(projects.core.model)

exposes those models
If you remove

nowinandroid/build-logic/convention/src/main/kotlin/AndroidFeatureConventionPlugin.kt

Line 42 in 7980c1d

add("implementation", project(":core:ui"))

It would still works because :core:data already exposes those models from

nowinandroid/core/database/build.gradle.kts

Line 33 in 7980c1d

api(projects.core.model)

It's just confusing me on which module really tells the truth. Sometimes it duplicates the dependency. Sorry for confusing you.

Also, in

nowinandroid/core/data/build.gradle.kts

Line 36 in 7980c1d

api(projects.core.datastore)

Does it mean that FEATURE Modules can actually see this class

nowinandroid/core/datastore/src/main/kotlin/com/google/samples/apps/nowinandroid/core/datastore/NiaPreferencesDataSource.kt

Line 29 in 7980c1d

class NiaPreferencesDataSource @Inject constructor(

[Jaehwa-Noh]

To sum up, Feature -> (implement) Core:UI -> (api) model
But, where did you find api(projects.core.datastore)?
I can't see the connection from Feature to Datastore.

[Jaehwa-Noh]

Aha, I found it.
I confused with Core:UI what you mentioned.

nowinandroid/feature/bookmarks/build.gradle.kts

Lines 27 to 28 in 7980c1d

	dependencies {
	implementation(projects.core.data)

Then the dependency like this.
Feature -> (implementation) data -> (api) datastore

As I shown you the documentation, data export datastore and Feature can see it.

it's letting Gradle know that the module wants to transitively export that dependency to other modules, so that it's available to them at both runtime and compile time.

And @yongsuk44 mentioned that, both were not directly connected. Look his comment.

[yongsuk44]

@JackEblan

As you mentioned, it is possible to access 'network', 'datastore', and 'database' from the 'feature' module. However, you need to understand that the 'feature' module does not directly depend on these modules instead, it accesses them indirectly through interfaces implemented by each Repository in the 'data' module.

Additionally, the reason the 'data' module uses 'api' is not just because it is used by the 'feature' module, but as you can see from the SyncWorker in the 'sync' module, it is used elsewhere too.