Eduard•3w ago

How can I avoid explicitly defining type in TypeScript for a internal call query handler?

I'm loving Convex <3, and I'd like to simplify my code. I have a query handler where I define a specific response type, but I want TypeScript to automatically infer the return type, instead of explicitly specifying something like GetMeResponse | null. Here’s an example of my current implementation:

type GetMeResponse = {
  _id: Id<"users">;
  name: string;
  email: string;
  role: string;
  isTutor: boolean;
  isStudent: boolean;
  stripeCustomerId?: string;
  imageUrl?: string;
};

export const getMe = query({
  handler: async (ctx): Promise<GetMeResponse | null> => {
    const userId = await getAuthUserId(ctx);
    if (!userId) return null;

    const user = await ctx.db.get(userId);

    if (!user) {
      throw new Error("User not found");
    }

    if (!user.name) {
      throw new Error("User name not found");
    }

    if (!user.email) {
      throw new Error("User email not found");
    }

    if (!user.role) {
      throw new Error("User role not found");
    }

    return {
      _id: userId,
      name: user.name,
      email: user.email,
      role: user.role,
      isTutor: user.role === ROLES.TUTOR,
      isStudent: user.role === ROLES.STUDENT,
      stripeCustomerId: user.stripeCustomerId,
      imageUrl: user.image,
    };
  },
});

export const getMeOrThrow = query({
  handler: async (ctx): Promise<GetMeResponse> => {
    const user: GetMeResponse | null = await ctx.runQuery(api.queries.users.getMe);

    if (!user) {
      throw new Error("User not found");
    }

    return user;
  },
});

type GetMeResponse = {
  _id: Id<"users">;
  name: string;
  email: string;
  role: string;
  isTutor: boolean;
  isStudent: boolean;
  stripeCustomerId?: string;
  imageUrl?: string;
};

export const getMe = query({
  handler: async (ctx): Promise<GetMeResponse | null> => {
    const userId = await getAuthUserId(ctx);
    if (!userId) return null;

    const user = await ctx.db.get(userId);

    if (!user) {
      throw new Error("User not found");
    }

    if (!user.name) {
      throw new Error("User name not found");
    }

    if (!user.email) {
      throw new Error("User email not found");
    }

    if (!user.role) {
      throw new Error("User role not found");
    }

    return {
      _id: userId,
      name: user.name,
      email: user.email,
      role: user.role,
      isTutor: user.role === ROLES.TUTOR,
      isStudent: user.role === ROLES.STUDENT,
      stripeCustomerId: user.stripeCustomerId,
      imageUrl: user.image,
    };
  },
});

export const getMeOrThrow = query({
  handler: async (ctx): Promise<GetMeResponse> => {
    const user: GetMeResponse | null = await ctx.runQuery(api.queries.users.getMe);

    if (!user) {
      throw new Error("User not found");
    }

    return user;
  },
});

Question: How can I avoid explicitly defining GetMeResponse | null and let TypeScript infer the types automatically for these Convex query handlers?

4 Replies

Convex Bot•3w ago

Thanks for posting in <#1088161997662724167>. Reminder: If you have a Convex Pro account, use the Convex Dashboard to file support tickets. - Provide context: What are you trying to achieve, what is the end-user interaction, what are you seeing? (full error message, command output, etc.) - Use search.convex.dev to search Docs, Stack, and Discord all at once. - Additionally, you can post your questions in the Convex Community's <#1228095053885476985> channel to receive a response from AI. - Avoid tagging staff unless specifically instructed. Thank you!

erquhart•3w ago

the getMe query doesn't require a return type, but getMeOrThrow does because it introduces circular inference. There's a doc about it here: https://docs.convex.dev/functions/actions#dealing-with-circular-type-inference Hmm actually you should be able to drop the return types for both

lee•3w ago

you're also using an unnecessary ctx.runQuery. we recommend helper functions https://docs.convex.dev/production/best-practices/#use-helper-functions-to-write-shared-code

Best Practices | Convex Developer Hub

Here's a collection of our recommendations on how best to use Convex to build

EduardOP•2w ago

Thanks @erquhart and @lee

How can I avoid explicitly defining type in TypeScript for a internal call query handler?

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