Preventing Firebase deletions -

i've written small single page javascript application (for internal company use) hosted on s3 , uses firebase datastore.

i'm aware devious hacker find way delete data in firebase if determined enough using javascript console.

none of data in application should ever deleted.

what firebase rules can use ensure data cannot deleted authorised user? possible?

thanks

yup, that's simple:

".write": "!data.exists() || newdata.exists()" 

so can write if there's either no data @ location or if you're writing new data.