feat: roles SPA foundations

web/src/lib/apiError.ts

@@ -1,12 +1,47 @@
+export const KNOWN_ERROR_CODES = [
+	'missing_permission',
+	'escalation',
+	'role_locked',
+	'own_role',
+	'role_built_in',
+	'built_in_name',
+	'role_conflict',
+	'user_role_changed',
+	'session_required',
+] as const
+
+export type ApiErrorCode = (typeof KNOWN_ERROR_CODES)[number]
+
+export interface ApiErrorDetails {
+	code?: ApiErrorCode
+	permission?: string
+	escalationKey?: string
+}
+
+const SESSION_REQUIRED_MESSAGE = 'This action needs a real session.'
+
+export function errorCodeOf(body: string | undefined): ApiErrorCode | undefined {
+	if (body === SESSION_REQUIRED_MESSAGE) {
+		return 'session_required'
+	}
+	return KNOWN_ERROR_CODES.find((code) => code === body)
+}
+
 export class ApiError extends Error {
 	status: number
 	retryAfter?: number
 	body?: string
+	code?: ApiErrorCode
+	permission?: string
+	escalationKey?: string
 
-	constructor(status: number, retryAfter?: number, body?: string) {
+	constructor(status: number, retryAfter?: number, body?: string, details: ApiErrorDetails = {}) {
 		super(`Request failed with status ${status}`)
 		this.status = status
 		this.retryAfter = retryAfter
 		this.body = body
+		this.code = details.code
+		this.permission = details.permission
+		this.escalationKey = details.escalationKey
 	}
 }