Errors

Every method returns [error, data, meta]. data and meta are null when error is set. Two-element destructuring still works; the third element is ignored.

interface ServiceError {
	message: string;
	status?: number;
	name?: string;
	details?: unknown;
	cause?: unknown;
}

name is Strapi's own error name ("ValidationError", "NotFoundError", …) when Strapi returned one, or one of "HTTPError", "TimeoutError", "NetworkError" for failures the client classifies itself. details is Strapi's error.details. cause is the thrown value on a network or timeout failure.

A missing document is { status: 404, name: "NotFoundError", message: "Not Found" }, including when Strapi answers 200 with an empty body on a read that must return a document.

Validation errors

A validation error carries field-level problems in details. Strapi shapes that differently per error. A rejected query param reports { source, param }, for instance, so details stays unknown and validationIssues reads the validation case:

import { validationIssues } from "@fbritoferreira/strapi";

const [err] = await articles.create({ payload: { data: {} } });
for (const issue of validationIssues(err)) {
	form.setError(issue.path.join("."), issue.message);
}

Each issue is { path: (string | number)[], message: string, name?: string }. The function returns [] for any error without that shape, including null. isValidationDetails narrows details directly.

const [err, created] = await articles.create({ payload: { data: { title: "" } } });
if (err) {
	if (err.name === "ValidationError") console.error(err.details);
	throw new Error(`${err.name}: ${err.message}`);
}

GraphQL errors are the same tuple: the whole errors array is details, and a single error's extensions.code is name (otherwise "GraphQLError"). See GraphQL.