Error Handling

{
	"type": "https://uptime.sergiodxa.com/docs/api/errors/not-found",
	"title": "The resource does not exist",
	"status": 404,
	"detail": "Monitor not found",
	"instance": "urn:uuid:0b6a4c1e-3f7d-4e8a-9c21-5d8f0a7b3e64"
}

{
	"type": "https://uptime.sergiodxa.com/docs/api/errors/validation-error",
	"title": "The request failed validation",
	"status": 400,
	"instance": "urn:uuid:5f1d2c3b-8a4e-4b6f-9d7c-2e1a0b9c8d7f",
	"errors": [
		{ "pointer": "/url", "code": "invalid", "message": "Expected a valid URL" },
		{
			"pointer": "/intervalSeconds",
			"code": "invalid",
			"message": "Expected a value of at least 60"
		}
	]
}

let response = await fetch("https://uptime.sergiodxa.com/api/v1/monitors", {
	method: "POST",
	headers: { Authorization: `Bearer ${apiKey}`, "Content-Type": "application/json" },
	body: JSON.stringify(data),
});

if (response.headers.get("Content-Type")?.startsWith("application/problem+json")) {
	let problem = await response.json();
	let name = problem.type.split("/").pop(); // "validation-error"
}

if (!response.ok) {
	let problem = await response.json();
	console.error(
		`API error ${problem.type} (${problem.instance}): ${problem.detail ?? problem.title}`,
	);
}

let userMessages: Record<string, string> = {
	"validation-error": "Please check your input and try again.",
	"limit-exceeded": "You've reached the maximum number of resources.",
	unauthorized: "Please sign in to continue.",
	forbidden: "You don't have permission to perform this action.",
	"not-found": "The requested resource could not be found.",
	"rate-limited": "Too many requests. Please wait a moment.",
	internal: "Something went wrong. Please try again later.",
};

async function fetchWithRetry(url: string, options: RequestInit, maxRetries = 3) {
	for (let attempt = 0; attempt < maxRetries; attempt++) {
		let response = await fetch(url, options);

		if (response.ok) return response;

		if (response.status === 429 || response.status >= 500) {
			let retryAfter = Number(response.headers.get("Retry-After"));
			let delay = retryAfter > 0 ? retryAfter * 1000 : Math.pow(2, attempt) * 1000;
			await new Promise((resolve) => setTimeout(resolve, delay));
			continue;
		}

		return response;
	}

	throw new Error("Max retries exceeded");
}