DataConnectAuth.kt: add authUid to GetAuthTokenResult

This change extracts the `user_id` and `sub` claims from the Firebase
Auth token and sends them to DataConnect as `authUids`.

* DataConnectAuth.kt:
    * Update `getToken` to include `authUids`
    * Update `GetAuthTokenResult` to hold `authUids`
    * Add `getAuthUids()` to extract UIDs from token claims
* arbs.kt:
    * Update `authTokenResult` to generate `authUids`

Author: dconeybe

firebase-dataconnect/src/main/kotlin/com/google/firebase/dataconnect/core/DataConnectAuth.kt

@@ -74,13 +74,31 @@ internal class DataConnectAuth(
   }
 
   override suspend fun getToken(provider: InternalAuthProvider, forceRefresh: Boolean) =
-    provider.getAccessToken(forceRefresh).await().let { GetAuthTokenResult(it.token) }
+    provider.getAccessToken(forceRefresh).await().let {
+      GetAuthTokenResult(it.token, it.getAuthUids())
+    }
 
-  data class GetAuthTokenResult(override val token: String?) : GetTokenResult
+  data class GetAuthTokenResult(override val token: String?, val authUids: Set<String>) :
+    GetTokenResult
 
   private class IdTokenListenerImpl(private val logger: Logger) : IdTokenListener {
     override fun onIdTokenChanged(tokenResult: InternalTokenResult) {
       logger.debug { "onIdTokenChanged(token=${tokenResult.token?.toScrubbedAccessToken()})" }
     }
   }
+
+  private companion object {
+
+    val authUidClaimNames = listOf("user_id", "sub")
+
+    fun com.google.firebase.auth.GetTokenResult.getAuthUids(): Set<String> = buildSet {
+      authUidClaimNames.forEach { claimName ->
+        claims[claimName]?.let { claimValue ->
+          if (claimValue is String) {
+            add(claimValue)
+          }
+        }
+      }
+    }
+  }
 }

firebase-dataconnect/src/test/kotlin/com/google/firebase/dataconnect/testutil/property/arbitrary/arbs.kt

@@ -51,6 +51,7 @@ import io.kotest.property.arbitrary.int
 import io.kotest.property.arbitrary.list
 import io.kotest.property.arbitrary.map
 import io.kotest.property.arbitrary.orNull
+import io.kotest.property.arbitrary.set
 import io.kotest.property.arbitrary.string
 import io.mockk.coEvery
 import io.mockk.mockk
@@ -333,9 +334,10 @@ internal inline fun <Data, reified Variables> DataConnectArb.operationRefConstru
 }
 
 internal fun DataConnectArb.authTokenResult(
-  accessToken: Arb<String> = accessToken()
-): Arb<GetAuthTokenResult> = accessToken.map { GetAuthTokenResult(it) }
+  accessToken: Arb<String?> = accessToken().orNull(nullProbability = 0.33),
+  authUids: Arb<Set<String>> = Arb.set(string(0..10, Codepoint.alphanumeric()), 0..10),
+): Arb<GetAuthTokenResult> = Arb.bind(accessToken, authUids, ::GetAuthTokenResult)
 
 internal fun DataConnectArb.appCheckTokenResult(
   accessToken: Arb<String> = accessToken()
-): Arb<GetAppCheckTokenResult> = accessToken.map { GetAppCheckTokenResult(it) }
+): Arb<GetAppCheckTokenResult> = accessToken.map(::GetAppCheckTokenResult)