Data validation rules in Firebase - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

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

Firebase

allow read: if request.auth [1] null;

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

A<

B==

C!=

D>

Attempts:

3 left

💡 Hint

Common Mistakes

Using '==' instead of '!=' causes access only for unauthenticated users.

Using comparison operators like '<' or '>' is invalid here.

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

2fill in blank

medium

Complete the code to allow write access only if the user's ID matches the document ID.

Firebase

allow write: if request.auth.uid [1] resource.id;

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

A==

B!=

C<=

D>=

Attempts:

3 left

💡 Hint

Common Mistakes

Using '!=' allows users to write data that is not theirs.

Using '<=' or '>=' is not meaningful for string IDs.

The rule request.auth.uid == resource.id ensures users can only write their own data.

3fill in blank

hard

Fix the error in the rule to allow writes only if the new data has a 'score' field that is a number.

Firebase

allow write: if request.resource.data.score [1] int;

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

Ais

Bin

Ctypeof

D==

Attempts:

3 left

💡 Hint

Common Mistakes

Using '==' compares the value to the string 'number', which is incorrect.

Using 'typeof' is not valid syntax in Firebase rules.

The is operator checks the data type of a field in Firebase rules.

4fill in blank

hard

Fill both blanks to allow writes only if the new data has a 'name' field that is a string and is not empty.

Firebase

allow write: if request.resource.data.name [1] string && request.resource.data.name.[2] > 0;

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

Ais

Blength

Csize

Dcount

Attempts:

3 left

💡 Hint

Common Mistakes

Using '==' instead of 'is' for type checking.

Using 'length' or 'count' which are not valid string properties in Firebase rules.

The is operator checks the type, and size gets the string length to ensure it's not empty.

5fill in blank

hard

Fill all three blanks to allow writes only if the user is authenticated, the 'age' field is a number, and the age is at least 18.

Firebase

allow write: if request.auth [1] null && request.resource.data.age [2] int && request.resource.data.age [3] 18;

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

A!=

Bis

C>=

D==

Attempts:

3 left

💡 Hint

Common Mistakes

Using '==' instead of '!=' for authentication check.

Using '<' instead of '>=' for age comparison.

This rule checks that the user is signed in, the age is a number, and the age is 18 or older.