Firebase Auth Emulator interferes with Firebase Storage

先閱讀 src/main/java/com/google/firebase/auth/internal/Utils.java 和 src/main/java/com/google/firebase/ImplFirebaseTrampolines.java，尤其關注 FIREBASE_AUTH_EMULATOR_HOST 和模擬器憑證的處理。在同時啟用 Auth 和 Storage 的情況下重現問題，然後驗證 Storage 呼叫仍保持授權狀態，而模擬器憑證僅套用於 Auth；另外也檢查不同的 FirebaseApp 執行個體是否可以使用不同的模擬器設定。

[READ] Step 1: Are you in the right place?

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  file a Github issue.
  • If this is a feature request make sure the issue title starts with "FR:".
• For general technical questions, post a question on StackOverflow
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• For help troubleshooting your application that does not fall under one
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[REQUIRED] Step 2: Describe your environment

• Operating System version: Windows 11
• Firebase SDK version: ____
• Library version: 9.1.1
• Firebase Product: auth, storage

[REQUIRED] Step 3: Describe the problem

We access the Auth and Storage services in our project using this Java Admin SDK.
Recently, we wanted to make use of the Auth Emulator for development purposes. However, after enabling the emulator by setting the FIREBASE_AUTH_EMULATOR_HOST environment variable, the Storage calls stop working and return 401 Unauthorized.

It seems that by setting the FIREBASE_AUTH_EMULATOR_HOST environment variable, the whole project enters an emulator mode and uses emulator credentials. The emulator credentials should be made to only apply to Auth calls.

Furthermore, I could not even find a way to create two instances of FirebaseApps (one with the emulator enabled and one disabled), since the check for FIREBASE_AUTH_EMULATOR_HOST is static and shared program-wide.

Steps to reproduce:

Use Auth and Storage in a production project. Enable FIREBASE_AUTH_EMULATOR_HOST and Storage stops working.