Are GraphQL Unions supported?

[tubaman]

When I run the code generator the output doesn't seem to work because GraphQL unions are treated like standard types. Are GraphQL unions supported?

[anntnzrb]

Yes, Ariadne fully supports GraphQL Unions. Use the UnionType class:

from ariadne import UnionType

search_result = UnionType("SearchResult")

@search_result.type_resolver
def resolve_search_result_type(obj, *_):
    if "username" in obj:
        return "User"
    if "title" in obj:
        return "Post"
    return None

schema = make_executable_schema(type_defs, search_result)

The type resolver examines the object and returns the concrete type name as a string.