server-queries

A powerful TypeScript-first userland implementation of server actions with more flexibility and support for data fetching.

This library is not a replacement but rather a powerful addition to the server actions in Next.js.

Features

• 🔒 Type-safe Server Queries: Full end-to-end type safety for your server-side queries.
• ⚡ Optimized Performance: Uses fetch requests under the hood with support for custom request options and abort signals.
• 🎯 React Query Integration: Seamless integration with TanStack Query for efficient data fetching and caching.
• 🛡️ Zod Validation: Built-in support for runtime validation using Zod schemas.
• 🎨 Improved DX: Usage is very similar to server actions which you already know and love.
• ⚡️ Fully Parallel: Execution of server queries and mutations takes place completely in parallel.
• 🔄 Automatic Code Transformation: Webpack loader automatically transforms client-side code to not import server-only code.
• 🎯 Uniform Error Format: All errors follow the standardized JSON:API error format for consistent error handling.

Installation

npm install server-queries
# or
yarn add server-queries
# or
pnpm add server-queries

Configuration

To use server-queries in your Next.js project, you need to configure the webpack loader. Add the following to your next.config.js:

/** @type {import('next').NextConfig} */
const nextConfig = {
  webpack: (config) => {
    config.module.rules.push({
      test: /\.(ts|tsx)$/,
      use: [
        {
          loader: "server-queries/webpack-loader",
        },
      ],
    });
    return config;
  },
};

module.exports = nextConfig;

Usage

1. Define Your Server Query

// ./src/server/my-query.ts
import { serverQuery } from "server-queries/server";
import { ServerQueryErr, ServerQueryOk } from "server-queries/results";

export const myQuery = serverQuery("my-query", async () => {
  const success = doSomethingOnTheServer();
  if (!success) {
    return ServerQueryErr({
      code: "some-error",
      title: "A server error occured",
    });
  }

  return ServerQueryOk({
    status: "ok",
  });
});

2. Add/Update the route handler.

Server queries and mutations use Next.js Route Handlers.
Create a new file in ./src/app/query/[id]/route.ts:

import { createRouteHandler } from "server-queries/server";

import { myQuery } from "@/server/my-query";

// Add all queries and mutations in the array.
// The request will only be handled for a query or mutation if it is
// registered in this function.
export const { GET, POST } = createRouteHandler([myQuery]);

3. Use the query in your react component.

[!IMPORTANT] Do not forget the import attributes!

The type is either server-query or server-mutation and the ID MUST match the specified ID of the server query / mutation.

// ./src/app/components/SomeComponent.tsx
import { useServerQuery } from 'server-queries/client';

// IMPORTANT: This library only works by adding the correct import attributes
// when importing the query or mutation in client code!!!
import { myQuery } from '@/server/my-query' with { type: "server-query", id: "my-query" };

export function SomeComponent() {
  const { data, isLoading, error } = useServerQuery(myQuery, {
    queryKey: ["my-query-key"],
  });

  if (isLoading) return <div>Loading...</div>;
  if (error) return <div>Error: {error.message}</div>;

  return (
    <div>
      <h1>{data.status}</h1>
    </div>
  );
}

Queries with input parameters.

Server queries can also support input parameters with schema validation.

The input is validated by the specified zod schema. If validation fails, a validation error is automatically returned from the query.

// ./src/server/my-query-with-input.ts
import { z } from "zod";
import { serverQuery } from "server-queries/server";
import { ServerQueryErr, ServerQueryOk } from "server-queries/results";

const schema = z.object({
  name: z.string(),
  age: z.number(),
});

export const myQueryWithInput = serverQuery(
  "my-query-with-input",
  async (input) => {
    const success = doSomethingOnTheServer({
      // Use the data from input.
      name: input.name,
      age: input.age,
    });
    if (!success) {
      return ServerQueryErr({
        code: "some-error",
        title: "A server error occured",
      });
    }

    return ServerQueryOk({
      status: "ok",
    });
  }
);

// ./src/app/components/SomeComponent.tsx
import { useServerQuery } from 'server-queries/client';

// IMPORTANT: This library only works by adding the correct import attributes
// when importing the query or mutation in client code!!!
import { myQueryWithInput } from '@/server/my-query-with-input' with { type: "server-query", id: "my-query-with-input" };

export function SomeComponent() {
  const { data, isLoading, error } = useServerQuery(myQueryWithInput, {
    queryKey: ["my-query-key"],
    // Pass the input here, can be state, props, etc.
    // But if so, do not forget to add the input to the query key!
    input: {
      name: "some-name",
      age: 40,
    },
  });

  if (isLoading) return <div>Loading...</div>;
  if (error) return <div>Error: {error.message}</div>;

  return (
    <div>
      <h1>{data.status}</h1>
    </div>
  );
}

Infinite Query

A Server Query can also be used with infinite loading, by using the useServerInfiniteQuery hook. Follow the TanStack Query Infinite Query docs for more info.

Server Mutations

A server mutation has the same purpose as a server action, except that server mutations can be triggered in parallel. When triggering a data mutation due to user interaction, use of a Server Action (!) is always preferred!

TODO: add documentation

Why Webpack Loader?

The webpack loader is a crucial part of the server-queries package.

To achieve a good DX similar to server actions, a server query / muation must be importable in the client code in order to directly use it in the desired hook.

This however leads to importing server code in a client component, which is very dangerous because the server-code will be bundled in the client code if not using import "server-only"!

The loader checks for all client code that imports a server query / muation using the correct import attributes (the with statement at the end).

The import is then rewritten to only import the type (this makes sure to not imoprt any actual server code), but keeps type-safety in tact by leaving the needed TypeScript information.

Code for a mock object is then injected into the source code which is asserted to the imported type of the query / mutation and thus making the TypeScript compiler happy. But the object only contains the correct ID and type of the server query / mutation, which is the minimal needed data for the caller to create the request to the route handler.

API Reference

Server-side

• serverQuery: Factory function to create a server query (GET request).
• serverMutation: Factory function to create a server mutation (POST request).
• createRouteHandler: Function to create the GET and POST route handler in Next.js.

Client-side

• useServerQuery: React hook for executing server queries.
• useServerInfiniteQuery: React hook for infinite loading queries.
• useServerMutation: React hook for executing a server mutation.
• ServerQueryConfigProvider: Context provider for global configuration.