firebase-tools: Allow emulators to export on exit

Originally requested through FIrebase support, there is some demand for a flag like this:

firebase emulators:start --import=./seed --export-on-exit

This would import from a location but save any mutations made on exit.

About this issue

Original URL
State: closed
Created 4 years ago
Reactions: 12
Comments: 19 (14 by maintainers)

Most upvoted comments

@michi88 thanks for asking all the right questions. My personal take:

I like the name --export-on-exit
I think it should take an optional path --export-on-exit=./some-path. When unspecified it would use the same path as --import. If you do a bare --export-on-exit with no --import=something flag that’s an error. So:
- ✅ VALID: emulators:start --import=./foo --export-on-exit
- ✅ VALID: emulators:start --import=./foo --export-on-exit=./bar
- ✅ VALID: emulators:start --export-on-exit=./bar
- ❌ NOT VALID: emulators:start --export-on-exit

If that sounds good to you I’ll propose it to the API people.

samtstern on Jun 16, 2020

Waiting with anticipation. I didn’t realise that data was not saved automatically after restarting and was wondering what was wrong with my app until I checked the db, I’m glad I’m not crazy.

quantuminformation on Jul 13, 2020

@michi88 totally makes sense, although right now we do want import and export to feel explicit and separate for the reason you said: they’re one-time expensive operations. Something like --data-dir implies that these emulators have a persistence layer, which they do not.

I’ll go ahead and kick this off.

samtstern on Jun 16, 2020