// https://angularfirebase.com/lessons/firestore-security-rules-guide/
// https://medium.com/@jek.bao.choo/my-firestore-security-rules-learning-notes-14316400f160
Scope Rules to Specific Operations Rules can be enforced on various read/write operations that occur in a clientside app. We can scope rules to each of the follow read operations.
allow read - Applies to both lists and documents. allow get - When reading a single document. allow list - When querying a collection.