Rule syntax and structure in Firebase - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to allow read access to all users.

Firebase

service cloud.firestore {
  match /databases/{database}/documents {
    match /{document=**} {
      allow read: if [1];
    }
  }
}

Drag options to blanks, or click blank then click option'

Arequest.auth != null

Bfalse

Ctrue

Drequest.time < timestamp.date(2020, 1, 1)

Attempts:

3 left

💡 Hint

Common Mistakes

Using false blocks all access.

Using request.auth != null restricts to signed-in users only.

Setting allow read: if true; means anyone can read the data.

2fill in blank

medium

Complete the code to allow write access only if the user is authenticated.

Firebase

service cloud.firestore {
  match /databases/{database}/documents {
    match /{document=**} {
      allow write: if [1];
    }
  }
}

Drag options to blanks, or click blank then click option'

Atrue

Brequest.time > timestamp.date(2023, 1, 1)

Cfalse

Drequest.auth != null

Attempts:

3 left

💡 Hint

Common Mistakes

Using true allows anyone to write.

Using false blocks all writes.

The condition request.auth != null checks if the user is signed in.

3fill in blank

hard

Fix the error in the rule condition to allow read only if the user is authenticated.

Firebase

service cloud.firestore {
  match /databases/{database}/documents {
    match /{document=**} {
      allow read: if [1];
    }
  }
}

Drag options to blanks, or click blank then click option'

Arequest.auth = null

Brequest.auth != null

Crequest.auth == null

Drequest.auth = true

Attempts:

3 left

💡 Hint

Common Mistakes

Using assignment = instead of comparison == or !=.

Checking for null with wrong operator.

The correct syntax to check authentication is request.auth != null.

4fill in blank

hard

Fill both blanks to allow write access only if the user is authenticated and the document ID matches the user ID.

Firebase

service cloud.firestore {
  match /databases/{database}/documents {
    match /users/[1] {
      allow write: if request.auth != null && request.auth.uid == [2];
    }
  }
}

Drag options to blanks, or click blank then click option'

A{userId}

Brequest.auth.uid

CuserId

Ddocument.id

Attempts:

3 left

💡 Hint

Common Mistakes

Using userId without braces in the path.

Using request.auth.uid instead of userId.

The path variable {userId} captures the document ID, and request.auth.uid is the signed-in user's ID.

5fill in blank

hard

Fill all three blanks to allow read access only to authenticated users and only for documents in the 'posts' collection where the post is published.

Firebase

service cloud.firestore {
  match /databases/{database}/documents {
    match /posts/[1] {
      allow read: if request.auth != null && resource.data.[2] == [3];
    }
  }
}

Drag options to blanks, or click blank then click option'

A{postId}

Bpublished

Ctrue

Dfalse

Attempts:

3 left

💡 Hint

Common Mistakes

Using false instead of true for published check.

Not capturing the document ID in the path.

The path variable {postId} captures the document ID. The rule checks if the published field is true and the user is authenticated.