[habosa]

Googler here: for those of you who have ever used Firebase this is the language that powers Cloud Firestore / Cloud Storage security rules.

Specifically in our rules everything after the "if" is Common Expression Language.

See: https://firebase.google.com/docs/firestore/security/rules-co...

The efficiency and safety of CEL enables us to put security rules in the critical path of every database request.

[_8ljf]

“this is the language that powers Cloud Firestore / Cloud Storage security rules”

This really needs to be stated on its front page. Right now it’s all “Hows” and no “Why”.

First question anyone looking at it asks: What problem does it solve?/What need does it fill? A real-world use case provides an easy relatable answer.

Incidentally, with existing links to protobuf and no halting problem to worry about, it sounds like you’re halfway to having a remote query language a-la SQL too.

https://www.researchgate.net/publication/221553413_Safe_Quer...

[alfnoodles]

The link given if for the spec, this is probably a better "intro" page: https://opensource.google/projects/cel

[saagarjha]

I actually looked at this thinking it was pretty cool and could come up with usecases immediately–it is a great way to do simple query/matching in a consistent way. If I'm not mistaken, this could be used for something like Gmail's advanced search? There are tons of interfaces where everyone designs their own ad-hoc expressions and having something like this would be very useful in those cases.