Firebase security rules syntax with arrays/list property - firebase

Within a Firebase Firestore collection with path 'organizations' each document contains a list of string userID's of users who can update or delete that document.
export interface Organization{
name?: string,
owners: string[]
}
I would like to create a Firebase security rule that ensures that only a logged in user with a uid that is in this list can edit or delete the object. Unsure of the appropriate syntax.
service cloud.firestore {
match /databases/{database}/documents {
match /organizations/{organization} {
allow read: if true;
allow create: if request.auth != null;
/// What should be the syntax here?
allow update, delete: if request.auth != null && (request.auth.uid in resource.data.owners); // <--------- What should be the syntax for this line?
}

Ok, answering my own question here in case it's useful for anyone else.
It looks like the 'in' syntax above actually works even-though it was a complete guess and I wasn't able to find any documentation for it in the firebase security roles documentation.
Final code:
service cloud.firestore {
match /databases/{database}/documents {
match /organizations/{organization} {
allow read: if true;
allow create: if request.auth != null;
allow update, delete: if (request.auth != null) && (request.auth.uid in resource.data.owners);
}

Related

Firebase Security Rules -- using attribute from User document

I'm struggling to make my Firebase security rules work.
I only want to allow write access to documents in the collection Nouns to users with the attribute 'admin' == true (boolean) in their user document (stored in collection Users).
rules_version = '2';
service cloud.firestore {
match /databases/{database}/documents {
match /Users/{userId}/{documents=**} {
allow read, write: if request.auth != null
&& request.auth.uid == userId
}
match /Nouns/{documents=**} {
allow read: if request.auth != null
}
match /Nouns/{documents=**} {
allow read, write: if request.auth != null
&& resource.data.admin == true
}
}
}
The rules playground gives the following error when I try a write on a document in the Nouns collection:
Error: simulator.rules line [17], column [13]. Property admin is undefined on object.
Can anyone please let me know what I'm doing wrong?
resource.data will contain data of the document being accessed in Nouns collection. If you want to read data from user's document, use get() instead:
match /Nouns/{documents=**} {
allow read, write: if request.auth != null
&& get(/databases/$(database)/documents/Users/$(request.auth.uid)).data.admin == true
}
Collection names are case-sensitive so make sure you enter it correctly.

How to manage rights in firebase to allow differents users to read/upate/write?

I've a firestore database and I now need to add a new collection.
Each entry of this collection should contain:
Which userId is the owner(field admin)
Which userId has been allowed to edit this element(field writer)
Which userId has been allowed to only read(field reader).
I'm currently only at the first step, and already strugling:
I was hoping to be able to query my collection( /trips/) and get only the one that I'm allowed to access, but I get an error:
FirebaseError: Missing or insufficient permissions.
Here is my rules file:
rules_version = '2';
service cloud.firestore {
match /databases/{database}/documents {
match /{document=**} {
allow read, write: if false;
}
match /users/{userId} {
allow read, update, delete: if request.auth != null && request.auth.uid == userId;
allow create: if request.auth != null;
}
match /trips/{trip} {
allow read, update, delete: if request.auth != null && request.auth.uid == resource.data.admin;
allow create: if request.auth != null;
}
}
}
So my questions:
Is this the correct way of managing resource that must be acceeded by multiple people(meaning, I cannot just have the userId in the path since there are multiple users)
How should I query only the documents list that I'm allowed to see?
Thank you very much for your help
As you will read in the doc, "All match statements should point to documents, not collections".
With
service cloud.firestore {
match /databases/{database}/documents {
match /trips {
// ....
}
}
}
you don't point to a document. You should use a wildcard to point to any document in the specified path, as follows:
service cloud.firestore {
match /databases/{database}/documents {
match /trips/{trip} {
// ....
}
}
}
Therefore the following should correctly implement your requirements:
rules_version = '2';
service cloud.firestore {
match /databases/{database}/documents {
match /trips/{trip} {
allow read: if request.auth != null &&
(request.auth.uid == resource.data.admin
|| request.auth.uid == resource.data.writer
|| request.auth.uid == resource.data.reader
);
allow update: if request.auth != null &&
(request.auth.uid == resource.data.admin
|| request.auth.uid == resource.data.writer
);
allow create: if request.auth != null;
}
}
}
Then, for the two questions:
Is this the correct way of managing resource that must be acceeded by multiple people (meaning, I cannot just have the userId in the path
since there are multiple users)
If the admin, writer and reader are specific for each document, yes this is the correct way. If those roles would be more global (e.g. all the trips to Europe can be edited by the same user), you could use a role based approach with Custom Claims.
How should I query only the documents list that I'm allowed to see?
It is important to note that rules are not filter. So your query for getting docs needs to be aligned with the rules. In your specific case, you could have an additional field of type Array which contains three values; the uids of the admin, writer and reader, and use the array-contains operator. Something like:
const user = firebase.auth().currentUser;
const query = db.collection("trips").where("authorizedReaders", "array-contains", user.uid);
match /{document=**} {
allow read, write: if false;
}
You don't need the above code as it will apply to all routes of the database, because of the above line you are getting the below error as it does not allow you to read and write to the database
FirebaseError: Missing or insufficient permissions.
Now, if you want to assign privileges to users then you should add the Role field to users collections which would have a value such as Admin, Editor, Reader
Then, you can check in routes something like below
match /users/{userId}/trips/{tripId} {
allow read, delete: if request.resource.data.role == "Admin";
allow create, update: if request.resource.data.role == "Admin || request.resource.data.role == "Editor";
}
If you want to know more about how to create a route check out this video for the best explanation

Firebase Security Rules - Undefined Resource Error

I have collection Users which has documents with the same Id as the user.uid. I want to allow logged in users to create documents and only update, delete and read their documents which is specified with the same UID as mentioned.
I tried this but it keeps failing.
rules_version = '2';
service cloud.firestore {
match /databases/{database}/documents {
match /users/{document} {
allow create, : if request.auth != null;
allow update, delete, read: if request.auth != null && request.auth.uid == request.resource.data.UID;
}
}
}
In this code i am trying to compare the uid of the logged user with a document field called UID
Have a look at the documentation, it shows exactly the response to your question.
service cloud.firestore {
match /databases/{database}/documents {
// Make sure the uid of the requesting user matches name of the user
// document. The wildcard expression {userId} makes the userId variable
// available in rules.
match /users/{userId} {
allow read, update, delete: if request.auth != null && request.auth.uid == userId;
allow create: if request.auth != null;
}
}
}
The key point is to use the {userId} wildcard expression to match the ID of the document being read/updated/deleted with the uid of the user (i.e. request.auth.uid);

How to set Firestore security rules? resource.data: Null value error

I need some help making my security rules for firestore work.
These are my firestore rules:
service cloud.firestore {
match /databases/{database}/documents {
match /orders/{orderID} {
allow read, update: if request.auth.uid == resource.data.buyerId || request.auth.uid == resource.data.sellerId;
}
}
}
my orders collection:
orders: {
sellerId: 'some-id',
createdAt: timestamp,
buyerId: 'some-id'
}
It should return all documents from orders collection which has either buyerId or sellerId equal to authorised user (request.auth.uid).
but the above rule is not working as expected.
firestore collections screenshot
firebase simulator output
That error message is suggesting that the requested document was not actually present in the database. You entered "orders/{orderId}", which looks like you put a wildcard in the Location field in the simulator. That's not going to work. You need to enter the path to an actual document that exists if you want to test your rule that uses its field values.
resource.data: Null - this error happens when you try to create a new entity.
Split write rule, on create and update.
rules_version = '2';
service cloud.firestore {
match /databases/{database}/documents {
match /user/{userId} {
allow read: if request.auth.uid == userId;
function authed() {
return request.auth.uid == userId;
}
allow create: if authed() && request.resource.data.keys().hasOnly(['name']);
allow update: if authed() && request.resource.data.diff(resource.data).changedKeys().hasOnly(['name']);
allow delete: if authed();
}
}
}

Cloud Firestore Security Rules documentation example

This documentation page: Writing conditions for Cloud Firestore Security Rules, says the following:
Another common pattern is to make sure users can only read and write their own data
And provides this example:
service cloud.firestore {
match /databases/{database}/documents {
// Make sure the uid of the requesting user matches name of the user
// document. The wildcard expression {userId} makes the userId variable
// available in rules.
match /users/{userId} {
allow read, update, delete: if request.auth.uid == userId;
allow create: if request.auth.uid != null;
}
}
}
I don't understand why the create rule is not defined with the same condition as the rest, if request.auth.uid == userId, but instead is defined with if request.auth.uid != null. As I understand it, with this rule any user can create any document inside users, but cannot do anything with it unless it matches his uid. So why allow it at all?
Let's talk about the very basic security rule that could be implemented (with user authentication):
allow read, update, delete: if request.auth.uid != null;
allow create: if request.auth.uid != null;
where any user can delete the documents of another people creation. So to restrict/control it, we implement as shown in the code snippet provided.
service cloud.firestore {
match /databases/{database}/documents {
// Make sure the uid of the requesting user matches name of the user
// document. The wildcard expression {userId} makes the userId variable
// available in rules.
match /users/{userId} {
allow read, update, delete: if request.auth.uid == userId;
allow create: if request.auth.uid != null;
}
}
}
The code snippet is just an example use case that uses different conditions for reference purposes as this is a tutorial/guide, so the Firebase team try to fit as many possible conditions to the code snippet.
You can, of course, do allow create: if request.auth.uid == userId; to strictly restricted to that particular user.
I hope it gives you some idea!

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