javascript - The Firebase security rules not works -


i have problem firebase rules. have root folder called 'users', containing many usersids again contains data, this:

users {     userid1 {         info_user {             a: {                 a1: whatever                 a2: whatever                        a3: {                     a3.1: whatever                     a3.2: whatever                     a3.3: whatever                     a3.n: whatever                 }             }             n: {} ...         }     },     userid2 {}, ...n }

everything work fine when running following code if there no security rules, such:

{rules {".read"  : true, ".write" : true}}  function getuserinfo () {     var dbref = firebase.database();     var myarray = [];     dbref.ref('users').on('child_added', function(snapshot) {         snapshot.foreach(function(childsnapshot) {             myarray = (childsnapshot.val().a3);             //         });     }); }

my challenge change security rules without change database structure.

so, tried this:

{     "rules" : {         ".read"  : false,         ".write" : false,         "users": {             "$userid": {                 "info_user": {                     "a":{                         ".read": "auth != null",                         ".write": "(root.child('r').child('w').haschild(auth.uid))",                         "a1":{".validate": "newdata.isstring()"},                         "a2":{".validate": "newdata.isstring()"},                         "a3":{".validate": "newdata.isstring()"}                     },                     "n": {                         ".read": "auth != null",                         ".write": "$user_id === auth.uid"                     }                 }             }         }     } }

the expected result read node a3 when user authenticated.

how this?

firebase database read permission enforced when first attach listener. when attach listener dbref.ref('users'), must have read permission /users. in security rules not case.

to make rules work, move read permission `users:

{   "rules" : {     "users": {       ".read"  : "auth != null",       ...

note permission cascades down. once grant user read permission on /users, have access data under /users. cannot take permission away specific node under there.

this leads 1 of pitfalls of securing firebase database: rules cannot used filter data. more on this, see firebase documentation on "rules not filters", answer it , many more of questions developers struggling concept.


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