Type 'Effect<{ message: string; }, CreatePasswordResetTokenError | ConfigError | CreatePasswordResetUrlError, never>' is not assignable to type 'Effect<{ readonly message: string; } | HttpServerResponse, CreatePasswordResetTokenError | CreatePasswordResetUrlError | HttpApiDecodeError | ConfigError, never>'.

[sundaray]

I am working on a Next.js project and I am trying to write the API endpoints using effect/platform.

I have run into a TS error that I am not able to solve even after consulting the LLMs.

Here is my app/effect/[[...path]]/route.ts file:

import { HttpApiBuilder, HttpServer } from "@effect/platform";
import { Layer } from "effect";
import { mainLayer } from "@/app/effect/server";

const WebHandlerLayer = Layer.mergeAll(mainLayer, HttpServer.layerContext)

const { handler } = HttpApiBuilder.toWebHandler(WebHandlerLayer);

export {
  handler as GET,
  handler as POST,
  handler as PUT,
  handler as DELETE,
  handler as PATCH,
  handler as HEAD,
  handler as OPTIONS,
};

Here is the app/effect/server.ts file:

import { HttpApiBuilder, HttpMiddleware } from "@effect/platform";
import { Layer } from "effect";

import { PodwiseApi } from "@/lib/api";
import { forgotPasswordHandler } from "@/lib/api/auth/handlers/forgot-password-handler";

const AuthGroupLive = HttpApiBuilder.group(PodwiseApi, "auth", (handlers) =>
  handlers
    .handle("forgotPassword", (req) => forgotPasswordHandler(req))

);

export const PodwiseApiLive = HttpApiBuilder.api(PodwiseApi).pipe(
  Layer.provide(AuthGroupLive),
);

const MiddlewareLive = HttpApiBuilder.middleware(HttpMiddleware.logger);

export const mainLayer = Layer.mergeAll(PodwiseApiLive, MiddlewareLive);

Here is the endpoint definition:

lib/api/auth/endpoints/index.ts:

import { HttpApiEndpoint, HttpApiGroup } from "@effect/platform";
import { Schema } from "effect";

import {
  ConfigError,
  CreatePasswordResetTokenError,
  CreatePasswordResetUrlError,
} from "@/lib/api/auth/errors";

// ============================================================================
// forgotPassword
// ============================================================================

const ForgotPasswordPayload = Schema.Struct({
  email: Schema.String,
});

const ForgotPasswordResponse = Schema.Struct({
  message: Schema.String,
});

export const ForgotPasswordError = Schema.Union(
  CreatePasswordResetTokenError,
  CreatePasswordResetUrlError,
  ConfigError,
);

const forgotPasswordEndpoint = HttpApiEndpoint.post(
  "forgotPassword",
  "/auth/forgot-password",
)
  .setPayload(ForgotPasswordPayload)
  .addSuccess(ForgotPasswordResponse)
  .addError(ForgotPasswordError);

/**************************************
 * authGroup
 *************************************/

export const authGroup = HttpApiGroup.make("auth")
  .add(forgotPasswordEndpoint)

Here is the group file:

lib/api/auth/group/index.ts:

import { HttpApiGroup } from "@effect/platform";

import { forgotPasswordEndpoint } from "@/lib/api/auth/endpoints";

export const authGroup = HttpApiGroup.make("auth").add(forgotPasswordEndpoint);

Here is the forgotPasswordHandler file:

import { HttpServerResponse } from "@effect/platform";
import { Effect } from "effect";

import { ConfigError } from "@/lib/api/auth/errors";

import "@/lib/api";

import { createPasswordResetSession } from "@/lib/create-password-reset-session";
import { createPasswordResetToken } from "@/lib/create-password-reset-token";
import { createPasswordResetUrl } from "@/lib/create-password-reset-url";
import { sendPasswordResetEmail } from "@/lib/send-password-reset-email";

export function forgotPasswordHandler(req: { payload: { email: string } }) {
  console.log("Request in forgtoPasswordHandler: ", req);
  const { email } = req.payload;

  const program = Effect.gen(function* () {
    const token = yield* createPasswordResetToken();
    const url = yield* createPasswordResetUrl(token);
  });

  const handledProgram = program.pipe(
    Effect.matchEffect({
      onFailure: (error) => Effect.fail(error),
      onSuccess: () => Effect.succeed({ message: "success" }),
    }),
  );

  return handledProgram;
}

Here is the createPasswordResetToken file;

import "server-only";

import { Effect } from "effect";
import { base64url } from "jose";
import { getRandomValues } from "uncrypto";

import { CreatePasswordResetTokenError } from "@/lib/api/auth/errors";

// ============================================================================
// Create password reset token
// ============================================================================

export function createPasswordResetToken() {
  return Effect.try({
    try: () => {
      const randomValues = new Uint8Array(32);
      getRandomValues(randomValues);
      return base64url.encode(randomValues);
    },
    catch: (error) =>
      new CreatePasswordResetTokenError({
        operation: "createPasswordResetToken",
        cause: error,
      }),
  }).pipe(Effect.tapError((error) => Effect.logError(error)));
}

Here is the passwordresetTokenUrl function:

import { Config, Effect } from "effect";

import { CreatePasswordResetUrlError } from "@/lib/api/auth/errors";

// ============================================================================
// Create password reset URL
// ============================================================================

export function createPasswordResetUrl(token: string) {
  return Effect.gen(function* () {
    const baseUrl = yield* Config.string("NEXT_PUBLIC_APP_URL").pipe(
      Config.withDefault("http://localhost:3000"),
    );

    const url = yield* Effect.try({
      try: () => {
        const url = new URL("/api/auth/verify-password-reset", baseUrl);
        url.searchParams.set("token", token);
        return url.toString();
      },
      catch: (error) =>
        new CreatePasswordResetUrlError({
          operation: "createPasswordResetURL",
          cause: error,
        }),
    });

    return url;
  }).pipe(Effect.tapError((error) => Effect.logError(error)));
}

The Errors

Currently, I am getting two TS errors.

Error-1

I am seeing a red squiggly error under forgotPasswordHandler on this line:

    .handle("forgotPassword", (req) => forgotPasswordHandler(req))

The error says:

Type 'Effect<{ message: string; }, CreatePasswordResetTokenError | CreatePasswordResetUrlError | ConfigError, never>' is not assignable to type 'Effect<{ readonly message: string; } | HttpServerResponse, CreatePasswordResetTokenError | CreatePasswordResetUrlError | ConfigError | HttpApiDecodeError, never>'.
  Type 'CreatePasswordResetTokenError | CreatePasswordResetUrlError | ConfigError' is not assignable to type 'CreatePasswordResetTokenError | CreatePasswordResetUrlError | ConfigError | HttpApiDecodeError'.
    Type 'And' is not assignable to type 'CreatePasswordResetTokenError | CreatePasswordResetUrlError | ConfigError | HttpApiDecodeError'.
      Type 'And' is not assignable to type 'HttpApiDecodeError'.
        Type 'And' is not assignable to type '{ readonly _tag: "HttpApiDecodeError"; }'.
          Types of property '_tag' are incompatible.
            Type '"ConfigError"' is not assignable to type '"HttpApiDecodeError"'.ts(2322)
HttpApiEndpoint.d.ts(237, 48): The expected type comes from the return type of this signature.
(alias) forgotPasswordHandler(req: {
    payload: {
        email: string;
    };
}): Effect<{
    message: string;
}, CreatePasswordResetTokenError | CreatePasswordResetUrlError | ConfigError, never>
import forgotPasswordHandler
No quick fixes available

I don't know what do I do to fix this error?

Error-2

I am getting another red squiggly error under WebHandlerLayer on the line below:

const { handler } = HttpApiBuilder.toWebHandler(WebHandlerLayer);

The error says:

Argument of type 'Layer<HttpPlatform | Generator | FileSystem | Path | Api, never, unknown>' is not assignable to parameter of type 'Layer<DefaultServices | Api, never, never>'.
  Type 'unknown' is not assignable to type 'never'.ts(2345)
const WebHandlerLayer: Layer.Layer<HttpPlatform | Generator | FileSystem | Path | Api, never, unknown>
No quick fixes available

Please help me fix these errors.

Note

please note that all errors go away if I remove the following line:

    const url = yield* createPasswordResetUrl(token);

from the forgotPasswordHandler file.