Errors¶

All error classes are exported from joltui and can be used with @handles.

Routing and authentication¶

Error	Raised when
`RouteNotFoundError`	No route matches the path.
`RouteParametersError`	A base-URL parameter is missing or invalid, or route parameters cannot be parsed.
`UnsupportedRouteParameterType`	A pattern uses a type other than `str` or `int`.
`RouteFailedError`	A navigation started by a link click failed (cause: the failure).
`AuthenticationError`	`isAuthenticated()` returned `false`, or a server component answered `401`. Has `path`.
`AuthorizationError`	`checkUserRoles()` returned `false`, or a server component answered `403`. Has `path` and `roles`.
`NotImplementedError`	`isAuthenticated` / `checkUserRoles` were needed but not overridden.

Components¶

Error	Raised when
`ElementInitializationError`	A component failed to initialize. Has `element`, `elementName`, `cause`.
`MethodExecutionError`	An event handler or lifecycle hook threw (cause: your error).
`RenderError`	`markup()` threw.
`MissingMarkupMethod`	A render was requested for a component without `markup`.
`DotJSEngineError`	A template could not be compiled or evaluated.
`DependencyLoadError`	A lazy dependency failed to load. Has `dependencyName`, `cause`.
`ElementDisconnectedError`	A component was removed while working. Cancellation; never sent to error handlers.

Server components¶

Error	Raised when
`NetworkError`	The request could not be completed.
`ServerComponentBadRequestResponse`	The server answered `400`.
`ServerComponentNotFound`	The server answered `404`.
`InternalServerError`	The server answered `5xx`.
`HttpRequestError`	Any other non-success status.
`MarkupFetchError`	A `2xx` response was empty or unreadable.

Wrapping¶

Source	Chain received by the handlers
Event handler	`MethodExecutionError` → your error
Lifecycle hook during initialization	`ElementInitializationError` → `MethodExecutionError` → your error
`markup()` during initialization	`ElementInitializationError` → `RenderError` → your error
Link-click navigation	`RouteFailedError` → the failure

Handlers match exact types (walking up the class hierarchy), then instanceof, then the cause. Use isElementCancellation(error) to recognise cancellation anywhere in a chain.