Firestore rules why this doesn't work? - google-cloud-firestore

I have tasks collection on root level and here is my rules (yeah, super global for now):
service cloud.firestore {
match /databases/{database}/documents {
match /{document=**} {
allow read: if resource.data.private == false;
allow write: if request.auth.uid != null;
}
}
}
Single task has field private: Boolean and I want to give read permission to all tasks that has private: false and writing is allowed only for logged in users.
firestore.collection('/tasks').onSnapshot(snapshot => {})
At least with onSnapshot this read rule doesn't work. I give an error:
Uncaught Error in onSnapshot: Error: Missing or insufficient permissions
So am I doing something wrong or what is happening here?

Apparently "you can't query data you have no access to". Because only private: false tasks are readable the query should be changed from this:
firestore.collection('/tasks').onSnapshot(snapshot => {})
to following:
firestore.collection('/tasks').where('private', '==', false).onSnapshot(snapshot => {})
after requesting only data I have access to, it started working!

Related

"FirebaseError: false for 'get' # L5" firebase error when using on snapshot or get doc when using firebase emulator [closed]

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I am using firestore and firebase auth and I am trying to add custom usernames to my app (I am following this courses, Next.js Firebase Full Course) that connect to the freebase emulator because it is still in development. I have this piece of code that runs in a useEffect that gets the current user uid and then fetch a document from firestore, then checks if it exits and if i does set the username state to the username in the do. Here is the code:
useEffect(() => {
let unsubscribe;
if (user) {
console.log(user.uid);
const ref = doc(db, "users", user.uid);
unsubscribe = onSnapshot(ref, (doc) => {
if (doc.exists()) {
setUsername(doc.data()?.username);
} else {
console.log("No such document!");
}
});
} else {
setUsername(null);
}
return unsubscribe;
}, [user]);
But I always get the error "next-dev.js?3515:32 Uncaught Error in snapshot listener: FirebaseError: false for 'get' # L5". I have tried changing the on snapshot to a get doc but that also gets the same error. I tried making it so it didn't connect to the emulator that fixed it. I'm not sure why but I like to use the firebase emulator. Is there anyway to fix this
Thanks in advance!
The error message “FirebaseError : false for ‘get’ #L5” is saying that security rules are denying the request at line 5 of your security rules. If you have curated your rules like below,
rules_version = '2';
service cloud.firestore {
match /databases/{database}/documents {
match /{document=**} {
allow read, write: if false;
}
}
}
then line 5 has the error as you are not allowing read and write access to anyone.
To fix that you can either change your firestore rules to :
match /{document=**} { allow read: if true; allow write: if true; }
but this allows setting your rules to true to both read and write operations, which means that you allow anybody who knows your project ID to read from, and write to your database which is obviously bad, since malicious users can take advantage of it. It’s true that you can use these settings for a small amount of time for testing purposes, but never in a production environment.
So there is another option in which you can limit access to your database to a fixed amount of time. Today is 1.03.2021, we are limiting the access for exactly one day by:
rules_version = '2';
service cloud.firestore {
match /databases/{database}/documents {
match /{document=**} {
allow read, write: if request.time < timestamp.date(2021, 3, 2);
}
}
}
The most important part when it comes to security rules is the Firebase Authentication, meaning that you can allow access only to the users that are authenticated to perform operations in your database. The rules should look like this:
rules_version = '2';
service cloud.firestore {
match /databases/{database}/documents {
match /{document=**} {
allow read, write: if request.auth != null;
}
}
}
If you need a more granular set of rules, for instance, to allow only the authenticated users, who have the value of the UID equal to the value of UID that comes from to authentication process, to be able to write to their own document, then you should consider using the following rules:
rules_version = '2';
service cloud.firestore {
match /databases/{database}/documents {
match /users/{uid} {
allow create: if request.auth != null;
allow read, update, delete: if request.auth != null && request.auth.uid == uid;
}
}
}
A feature request is filed for this error message to be more precise like “FirebaseError: PERMISSION_DENIED because security rules returned false for 'get' # L5”

firestore rules, permission errors

Im trying to figure out how the rules in Firestore work, and have stumbled upon a problem I cant quite figure why is failing.
When using the Firestore Rules Playground and do a get request for a document in /apps, I get the following error: "Error running simulation — Error: simulator.rules line [10], column [14]. Null value error."
And from the app im getting: FirebaseError: Missing or insufficient permissions
The location in trying to get: "/apps/0aKQw0MiRzEbrLDvsnI3"
rules_version = '2';
service cloud.firestore {
match /databases/{database}/documents {
match /{document=**} {
allow read, write: if isUserAuthenticated();
}
/* Functions */
function isUserAuthenticated() {
return request.auth.uid != null;
}
}
}
The thing im trying achieve is to allow read access for all document, and only write access if a user is signed in
I have no idea why it's failing on a get request?
If I'm not mistaken the way you added the read condition seems to be incorrect. Perhaps try this and see if it works for you.
match /databases/{database}/documents { match /{document=**} { allow read: if true, write: if request.auth != null && request.auth.uid!=null }

Don't get the simplest FireStore security rule to work as if it would not find my file - though looks like examples

I don't get this running, no matter what I do. I have already removed all rules, nevertheless I get simulated read denied. I habe tried companies/4U4kZKXkr3rHA6B04S5K and /companies/4U4kZKXkr3rHA6B04S5K as location, copy pasted the document id and the collection multiple times, nothing... To me, it looks just like all the running examples, I found
What am I doing wrong?!
UPDATE: I used these rules before, which did not work:
match /databases/{database}/documents {
// the request object contains info about the authentication status of the requesting user
// if the .auth property is not set, the user is not signed in
function isSignedIn() {
return request.auth != null;
}
// return the current users entry in the employees collection
function getEmployeeData() {
return get(/databases/$(database)/documents/employees/$(request.auth.uid)).data
}
// check if the current user has access to specific company
function accessCompany(companyId) {
return isSignedIn() && getEmployeeData()['companyId'] == companyId;
}
// check if the current user has a specific role
function hasRole(role) {
return isSignedIn() && getEmployeeData()[role] == true;
}
// check if the user has any of the given roles (list)
//function hasAnyRole(roles) {
// return isSignedIn() && getRoles().keys().hasAny(roles);
//}
}
match /users/{user} {
// anyone can see a specific users profile data (name, email etc), in a real scenario you might want to make this more granular
allow get: if true;
// noone can query for users
allow list, create: if false;
// users can modify their own data
allow update, delete: if request.auth.uid == user;
}
match /employees/{user} {
// only allow admins to set roles. Of course a user should be able to retrieve its own designated roles
allow get: if request.auth.uid == user || hasRole('admin');
allow list: if hasRole('admin');
allow update: if hasRole('admin');
allow create, delete: if false;
}
match /companies/{document=**} {
allow get, list, create, update, delete: if true;
}
}
By default, no read and write access is allowed to any document. If you want to allow access to a document, you must have at least one rule that matches the query that would allow that access. If you have commented out all your rules, then I would expect no reads or writes to be allowed.
Minimally, adding a rule like this will allow read access to all documents in the companies collection:
match /companies/{id} {
allow read: if true;
}
I suggest reviewing the documentation on security rules to better learn how they work.

Firebase Security rules to restrict access on all paths but one?

Question:
For the different top-level firestore collections below, how to restrict access to all but one of the paths?
We are building a data schema in Firestore to support a chat app for teachers across multiple schools.
The top-level firestore collections include:
/siteAdminUsers
/schools
/schools/{schoolId}/teachers
/schools/{schoolId}/chats
Below is the security rules setup we are trying now - where we check for:
valid user auth
expected value exists in userClaim variable request.auth.token.chatFlatList
However, the read listener for /messages is being blocked.
Error message:
FirebaseError: [code=permission-denied]: Missing or insufficient permissions
service cloud.firestore {
match /databases/{database}/documents {
match /{document=**} {
allow read, write: if false;
}
match /schools/{schoolId}/chats/{discussionId}/messages {
allow write: if false;
allow read: if request.auth != null
&& request.auth.token != null
&& request.auth.token.chatFlatList.val().contains($discussionId);
}
}
Details
We are using cloud functions for all data read/write, so for almost every case we can just block all client access.
The one exception is for the chat discussions, where we need to set a snapshot listener in the mobile client to know when there are new messages.
Sub-collection notes:
At a school, there are discussion sessions for school staff (teachers, admins, etc)
/schools/{schoolId}/chats/{discussionId}
Where each discussion-document contains:
list of participant teacher ids
subcollection for actual messages where each document is an indivual posted message:
/schools/{schoolId}/chats/{discussionId}/messages
User Claim code from Cloud Function
Looking at the cloud function logs, we have verified that the userClaim is being set.
return firebaseAdmin
.auth()
.setCustomUserClaims(
uid, {
chatFlatList: 'id1 id2 id3'
}
);
UPDATE #1
Tried the following variation where rules skip/omit the check on userClaim and auth.token.
However, still same permission error.
service cloud.firestore {
match /databases/{database}/documents {
match /{document=**} {
allow read, write: if false;
}
match /schools/{schoolId}/chats/{discussionId}/messages {
allow write: if false;
allow read: if request.auth != null;
}
}
}
I think the issue here is that you are writing a rule on the collection called messages.
All match statements should point to documents, not collections.
https://firebase.google.com/docs/firestore/security/rules-structure
You should try adding /{document=**} after your path to messages, something like:
match /schools/{schoolId}/chats/{discussionId}/messages/{document=**} {
allow write: if false;
allow read: if request.auth != null;
}
This worked for me if I wanted to read and write all collection but not one collection named "backStage";
rules_version = '2';
service cloud.firestore {
match /databases/{database}/documents {
match /{collection}/{document} {
allow read: if true
allow write: if (collection != "backStage");
}
}
}
Here's a solution (seems to be working), which includes the check on chatFlatList user claim variable (from original question) for a substring :
match /schools/{schoolId}/chats/{discussionId}/messages {
allow write: if false;
allow read: if request.auth != null
&& request.auth.token.chatFlatList.matches(discussionId);
}
Figured this out thanks to:
Firebase storage rules based on custom parameters
Here the post shows there is not any $ notation to access the path var. I recall seeing this in a security rules example code example - maybe it's specific to database tiers?
https://firebase.google.com/docs/reference/security/storage/#string
https://regex-golang.appspot.com/assets/html/index.html
Trying some example inputs here, to get an understanding for how to create the regex's.

Trigger permissions in Firestore

I've been able to set permissions to my Firestore database, the logic behind the rule is restrict users to be authenticated and belong to a specific domain.
service cloud.firestore {
match /databases/{database}/documents {
match /{document=**} {
allow read, write: if isUserAndSignedIn();
}
}
function isUserAndSignedIn(){
return request.auth != null && request.auth.token.email.matches('.*#domain[.]com')
}
}
The rule works fine for CRUD operations as expected but it doesn't work for triggers, in my case I'm getting the following error when the trigger is executed (cloud function):
FirebaseError: Missing or insufficient permissions.
at new FirestoreError (/srv/node_modules/#firebase/firestore/dist/index.node.cjs.js:348:28)
at JsonProtoSerializer.fromRpcStatus (/srv/node_modules/#firebase/firestore/dist/index.node.cjs.js:5385:16)
at JsonProtoSerializer.fromWatchChange (/srv/node_modules/#firebase/firestore/dist/index.node.cjs.js:5883:44)
at PersistentListenStream.onMessage (/srv/node_modules/#firebase/firestore/dist/index.node.cjs.js:14779:43)
at /srv/node_modules/#firebase/firestore/dist/index.node.cjs.js:14708:30
at /srv/node_modules/#firebase/firestore/dist/index.node.cjs.js:14748:28
at /srv/node_modules/#firebase/firestore/dist/index.node.cjs.js:10612:20
at <anonymous>
at process._tickDomainCallback (internal/process/next_tick.js:228:7)
Any Idea how can I solve this in the rule?
how can I bypass a trigger in the rules execution for the database?