Simple project gradle build script with flavours

build.gradle

android {
    ...
   
    defaultConfig {
        ...
        buildConfigField "String", "API_URL", "http://default-url.com"
        buildConfigField "String", "THIRD_PARTY_API_KEY", "rAnDomKeYF0rS3rV1ce"
    }
    
    productFlavors {
        development{
        }
        staging {
            buildConfigField "String", "API_URL", "https://staging-url.com"
            buildConfigField "String", "THIRD_PARTY_API_KEY", "rAnDomKeYF0rS3rV1ceSt4g1ng"

        }
        production {
            buildConfigField "String", "API_URL", "https://production-url.com"
            buildConfigField "String", "THIRD_PARTY_API_KEY", "rAnDomKeYF0rS3rV1cePr0duct10n"
        }
    }
    
    ...

}