Typescript potentially null

[luwol03]

Question about GraphQL Shield

In the following example typescript tells me, that ctx.user is potentially null as I defined the types for my context. However, my shield already filters that case out. But typescript doesn't recognize that. Is there some way to fix that without adding in every resolver a separate check and without using a ! After every ctx.user!.id?

Context:

export interface Context {
  request: Request;
  response: Response;
  prisma: PrismaClient;
  user: User | null;
}

export async function createContext(
  request: ExpressContext
): Promise<Partial<Context>> {
  const context: Context = {
    ...request,
    response: request.res,
    request: request.req,
    prisma: prisma,
    user: null,
  };

  const userId = getUserId(context);
  if (userId) {
    context.user = await prisma.user.findFirst({
      where: {
        id: userId,
      },
      rejectOnNotFound: true,
    });
  }

  return context;
}

Shields:

const isAuthenticated = rule({ cache: 'contextual' })(
  async (_parent, _args, ctx: Context) => {
    return ctx.user !== null;
  }
);

const permissions = shield({
  Query: {
    '*': isAuthenticated,
  },
  Mutation: {
    '*': isAuthenticated,
    login: allow,
    signup: allow,
    refreshAuth: allow,
    logout: allow,
  },
});

Mutation:

export const voteItem = mutationField('voteItem', {
  type: nullable(Vote),
  args: {
    where: nonNull(ItemWhereUniqueInput),
  },
  resolve: async (_root, args, ctx) => {
    return ctx.prisma.vote.create({
      data: {
        user: {
          connect: {
            id: ctx.user.id
          }
        },
        item: {
          connect: {
            id: args.where.id,
          },
        },
      },
    });
  },
});

• I have checked other questions and found none that matches mine.

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