Emulator support for database commands

It would be great to be able to use the database commands, such as database:get, database:set, and firestore:delete to interact with the emulator suite.

Since the emulator mentions setting the environment variable FIREBASE_DATABASE_EMULATOR_HOST=localhost:9000, then maybe it could work by detecting that variable.

To load the projects path from the emulator instead of the hosted instance, it would be great do the following: FIREBASE_DATABASE_EMULATOR_HOST=localhost:9000 firebase database:get /projects

It would also be great to have this for Firestore delete: FIRESTORE_EMULATOR_HOST=localhost:8080 firebase firestore:delete /projects/ABC123

NOTE: This has already been submitted as a feature request through the support page. The response was that the feature would be created on my behalf - creating this since one doesn’t appear to have been created.

[samtstern]

In #2109 this was fixed for almost all commands where emulator support is reasonable. All you have to do is export FIREBASE_DATABASE_EMULATOR_HOST=... or export FIRESTORE_EMULATOR_HOST=.... in your environment and the commands will target the emulators.

For example:

# Assume the database emulator is running on port 9000
FIREBASE_DATABASE_EMULATOR_HOST=localhost:9000 firebase database:get /foo/bar

or:

# Assume the direstore emulator is running on port 8080
FIRESTORE_EMULATOR_HOST=localhost:8080 firebase firestore:delete --recursive /foo

The big exception is database:remove because that command is implemented in a pretty complex way and I didn’t feel comfortable modifying it. For those who need database:remove in the emulator please file a new issue and we will discuss it there, I think this broad umbrella issue should be closed.

All database:* and firestore:* commands which do NOT support the emulators will now warn you if you try to execute them with the environment variables set to make sure you don’t accidentally affect production.

[samtstern]

@yuchenshi we recently started setting FIRESTORE_URL in emulators:foo so this won’t be a more breaking change (although we didn’t consider that one breaking the time I can see how it is).

The good news is if anyone gets broken it will be: you accidentally didnt write to prod. Which is way better than the reverse.