add environment variable to point admin sdk at rtdb emulator

[jmwski]

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[jmwski]

Abandoned and replaced by #596

[ryanpbrewster]

I think we need to re-open this PR and discuss using fake credentials for the emulators. Right now we're requiring developers to either do this themselves, or use a real production service account credential.

[schmidt-sebastian]

If I am not mistaken, the protocol is omitted in FIRESTORE_EMULATOR_HOST. I see that it might make sense to include it here (since we need to include the namespace). Should we come up with a consistent pattern that apploes to both RTDB and Firestore? @ryanpbrewster

[ryanpbrewster]

the protocol should not be included in the FIRESTORE_EMULATOR_HOST variable.

[schmidt-sebastian]

Do we care about the consistency between FIRESTORE_EMULATOR_HOST and FIREBASE_DATABASE_EMULATOR_HOST?

[ryanpbrewster]

Yes, ideally neither should include the protocol.

[jmwski]

This comment is dated, neither emulator host variable has a protocol.

[emersonreisdev]

I totally agree with reopening this, or at least reverting #602

I am wondering how a new feature in the Firebase JS SDK is sufficient for the firebase-admin Node SDK?

For example, I am using firebase-admin with firebase-functions and I do not touch the firebase JS client SDK and having this in the admin SDK would be really appreciated.

The only weird thing I found is that if I run the emulators using emulators:start and manually invoke the functions it seems to work, but if I try to automate the steps using emulators:exec it doesn't work.

[samtstern]

@dungahk can you open a new issue on the firebase-tools repo describing the issue you're having with emulators:exec versus emulators:start?