Validate that any arguments of this type are one of the allowed values Communicate through the type system that a field will always be one of a finite set of values enum Episode { NEWHOPE EMPIRE JEDI }

What are Enum types?

Difficulty: 5/10

enum definition, schema evolution, federation consistency

Enum types, also known as enumeration types, are a special kind of scalar that is restricted to a particular set of allowed values.

This allows you to:

1
Validate that any arguments of this type are one of the allowed values
2
Communicate through the type system that a field will always be one of a finite set of values

Here’s what an Enum type definition looks like in SDL:

Scenario Questions

0-2 years experience

1We need to add a new status field to our GraphQL schema that can only be 'OPEN', 'CLOSED', or 'PENDING'. How would you define this using an enum, and what would a client query look like?
2If a client sends a value not listed in the enum, what does GraphQL do, and how would you handle that in your resolver?

2-5 years experience

1Our product team wants to deprecate the 'PENDING' value in the OrderStatus enum and replace it with 'IN_REVIEW'. How would you modify the schema to support this change without breaking existing clients?

What are Enum types?

Enum types, also known as enumeration types, are a special kind of scalar that is restricted to a particular set of allowed values.

Scenario Questions

Follow-up Questions