Function tryCatchAsync

tryCatchAsync<A>(
f: () => Promise<A>,
onError: (error: unknown) => ServiceError,
): Promise<ServiceResult<A>>

Converts a promise returning function into a ServiceResult by handling potential rejections. If the promise returning function resolves successfully, returns a success ServiceResult. If the promise rejects, calls the onError function to convert the error into a ServiceError.

Type Parameters

A
The type of the value the promise resolves to

Parameters

f: () => Promise<A>
Function returning a Promise to execute. Passing a function allows catching synchronous throws
onError: (error: unknown) => ServiceError
Maps unknown errors to a ServiceError

Returns Promise<ServiceResult<A>>

A promise that resolves to a ServiceResult

Example

import { ok, strictEqual } from "node:assert/strict";

import { isFailure, isSuccess, ServiceError, tryCatchAsync } from "@clipboard-health/util-ts";

async function example() {
  const successResult = await tryCatchAsync(
    async () => {
      const response = await fetch("https://jsonplaceholder.typicode.com/posts/1");
      return (await response.json()) as { id: number };
    },
    (error) => new ServiceError(`Failed to fetch: ${String(error)}`),
  );

  ok(isSuccess(successResult));
  strictEqual(successResult.value.id, 1);

  const failureResult = await tryCatchAsync(
    async () => await Promise.reject(new Error("Network error")),
    (error) => new ServiceError(`Failed to fetch: ${String(error)}`),
  );

  ok(isFailure(failureResult));
  strictEqual(failureResult.error.issues[0]?.message, "Failed to fetch: Error: Network error");
}

// eslint-disable-next-line unicorn/prefer-top-level-await
void example();