Allow services to throw an error on non-2XX response

[rigtigeEmil]

Description

Migrating from the old library, we've leaned into the exception-throwing to handle errors and generically display an issue whenever an error is thrown. Something like this is what we've used up until now, and has been very nice to use.

export const useApiErrorToast = (error: any, onError?: (error: ApiError) => void) => {
	const toast = useToast();
	if (error instanceof ApiError) {
		onError?.();

		if (error.status >= 500) {
			toast.add({
				title: `${error.status}`,
				description: error.body.message,
				color: 'red',
			});
			return;
		}

		if (error.status >= 400 && error.status < 500) {
			toast.add({
				title: `${error.status}`,
				description: error.body.message,
				color: 'orange',
			});
			return;
		}
	}
	toast.add({
		title: 'Something went wrong',
		color: 'red',
	});
};

The new fetch client does not seem to offer similar functionality, nor is there a (to me) obvious way of achieving something similar, especially since the error response is unknown.

[mrlubos]

@rigtigeEmil can you provide a more detailed example with the old client?

[rigtigeEmil]

Yeah of course. Just be clear, what I mean is the old library, where the concept of a client didn't really exist as it does now.
I'm using Vue for my front-end where I use the client, and there's a few helper functions built in (from VueUse, for those that know). The one I use for almost all of my requests automatically sets a loading state while the response is in progress with a bunch of other goodness.

Today, with the old openapi library I have generated services to reflect my API. For customers, it looks like this:

export class CustomersService {

    /**
     * @param requestBody 
     * @returns string Created
     * @throws ApiError
     */
    public static createCustomer(
requestBody: CustomerCreateRequest,
): CancelablePromise<string> {
        return __request(OpenAPI, {
            method: 'POST',
            url: '/api/customers',
            body: requestBody,
            mediaType: 'application/json',
            errors: {
                400: `Bad Request`,
            },
        });
    }
// other endpoints

When using this to create a customer, I invoke the endpoint like so:

const { isLoading, execute: createCustomer } = useAsyncState(async (customer: CustomerCreateRequest) => {
	const id = await CustomersService.createCustomer(customer);
	const toast = useToast();
	toast.add({ title: 'Customer created', color: 'green', actions: [{ label: 'View', to: `/customers/${id}` }] });
	emit('created', id);
}, null, {
	immediate: false,
	onError: error => useApiErrorToast(error),
});

The problem I'd like to somehow solve with the upgrade to the new library is this onError: error => useApiErrorToast(error) functionality. Of course, I could do something similar to wrap around the service call, but the immediately easiest solution (for me) would be if there was a way to cause the new services to throw an exception (like the old library), when a non 2XX-response is returned from the API.

Hope it makes sense!

[rigtigeEmil]

I think I'd have a better time translating it to the new client stuff, but I'm also running into this issue
#641

[mrlubos]

Yeah I think addressing #641 would be easier, this is essentially asking for a completely different response shape and client behaviour which at this point isn't supported

[mrlubos]

@rigtigeEmil In the next release, you'll be able to pass throwOnError: true to the client/service/request. Please let me know if that solves your issues!