【Compose Multiplatform】Using ROOM Database in CMP - [KSP2] Annotation value is missing in nested annotations

• Note 1. Room version 2.7.0-alpha01 and above supports KMM.

• Note 2. When importing ksp, you might encounter issues with version incompatibility due to different Kotlin versions
  and fail to Build
  In this case, you can check the official GitHub for supported versions: ksp releases
  

• Note 3. Using Kotlin with ksp will check for ksp version and Kotlin compatibility
  When using Kotlin 2.0.0, during gradle sync you might see errors about version incompatibility
  such as Cannot change attributes of configuration ':composeApp:debugFrameworkIosX64' after it has been locked for mutation
  or [KSP2] Annotation value is missing in nested annotations
  
  Initially, I found a solution for the KSP2 issue
  by adding ksp.useKSP2=true in gradle.properties
  
  However, even after solving this issue
  and passing gradle sync
  you’ll encounter problems when configuring Room with ksp
  For example, after setting up ksp(libs.androidx.room.compiler)
  you’ll consistently get missing dao errors: [ksp] [MissingType]: xxxxx 'data.xxx.xxxDao' references a type that is not present
  
  After researching this issue
  Some suggest downgrading the Kotlin version to match ksp
  But since the official Wizard for CMP now defaults to Kotlin 2.0.0
  and following the principle of using newer rather than older versions XD
  If you want to successfully set up Room with Kotlin 2.0.0, you’ll need to use a workaround
  You can refer to the methods below until an official solution is available
  
  
  I’ll provide methods below
  that you can reference
  
  Additionally, I’ve seen that other developers have already reported issues to the official team:
  

  • Issue 1
  • Issue 2
  • Issue 3

• Step 1. Import Room

  • Add the following to your .toml file:

  • Add plugin to build.gradle.kts:

  • Add library to build.gradle.kts:

  • Add the following code to the outer layer of build.gradle.kts:

  • If you’re using Kotlin version greater than 1.9.20, add the following to gradle.properties:

• Step 1. Modify ksp version:

• Step 2. Adjust build.gradle.kts:
  
  • Add build/generated/ksp/metadata to the kotlin block
    
  • Use the add method to import ksp
    
  • Add tasks.withType to the outer layer
    
• Step 3. Implement RoomDatabase using a workaround
  
  This is the current workaround
  If you’re using Kotlin 2.0.0, you’ll need to do this
  as we need to wait for the official team to resolve compatibility issues
  

Implement AppDataBase builder

Koin:

Implement AppDataBase builder

Koin:

Implement AppDataBase

Dao

Entity

• KMM official documentation on importing ksp
• Android Studio Room documentation
• KMM Room support documentation
• ksp2
• issuetracker