```js
// @noErrors
import { isValidationError } from '@sveltejs/kit/remote';
```

## isValidationError

<blockquote class="since note">

Available since 2.47.3

</blockquote>

Checks whether this is a validation error thrown by [`invalid`](/docs/kit/@sveltejs-kit#invalid).

<div class="ts-block">

```dts
function isValidationError(
	e: unknown
): e is import('@sveltejs/kit/remote').ValidationError;
```

</div>



## InvalidField

A function and proxy object used to imperatively create validation errors in form handlers.

Access properties to create field-specific issues: `issue.fieldName('message')`.
The type structure mirrors the input data structure for type-safe field access.
Call `invalid(issue.foo(...), issue.nested.bar(...))` to throw a validation error.

<div class="ts-block">

```dts
type InvalidField<T> =
	WillRecurseIndefinitely<T> extends true
		? Record<string | number, any>
		: NonNullable<T> extends
					| string
					| number
					| boolean
					| File
			? (message: string) => StandardSchemaV1.Issue
			: NonNullable<T> extends Array<infer U>
				? {
						[K in number]: InvalidField<U>;
					} & ((message: string) => StandardSchemaV1.Issue)
				: NonNullable<T> extends RemoteFormInput
					? {
							[K in keyof T]-?: InvalidField<T[K]>;
						} & ((
							message: string
						) => StandardSchemaV1.Issue)
					: Record<string, never>;
```

</div>

## LiveQueryRequestedResult

<div class="ts-block">

```dts
type LiveQueryRequestedResult<Validated, Output> = Iterable<
	LiveRequestedEntry<Validated, Output>
> &
	AsyncIterable<LiveRequestedEntry<Validated, Output>> & {
		/**
		 * Call `reconnect` on all live queries selected by this `requested` invocation.
		 * This is identical to:
		 * ```ts
		 * import { requested } from '$app/server';
		 *
		 * for await (const { query } of requested(liveQuery, ...)) {
		 *   void query.reconnect();
		 * }
		 * ```
		 */
		reconnectAll: () => Promise<void>;
	};
```

</div>

## LiveRequestedEntry

A single entry yielded by [`requested`](/docs/kit/$app-server#requested)
when called with a `query.live`. `arg` is the validated argument; `query` is a
`RemoteLiveQuery` bound to the client's original cache key, so `reconnect()` targets
the correct client subscription.

<div class="ts-block">

```dts
type LiveRequestedEntry<Validated, Output> = {
	arg: Validated;
	query: RemoteLiveQuery<Output>;
};
```

</div>

## QueryRequestedResult

<div class="ts-block">

```dts
type QueryRequestedResult<Validated, Output> = Iterable<
	RequestedEntry<Validated, Output>
> &
	AsyncIterable<RequestedEntry<Validated, Output>> & {
		/**
		 * Call `refresh` on all queries selected by this `requested` invocation.
		 * This is identical to:
		 * ```ts
		 * import { requested } from '$app/server';
		 *
		 * for await (const { query } of requested(getPost, ...)) {
		 *   void query.refresh();
		 * }
		 * ```
		 */
		refreshAll: () => Promise<void>;
	};
```

</div>

## RemoteCommand

The type of a remote `command` function. See [Remote functions](/docs/kit/remote-functions#command) for full documentation.

<div class="ts-block">

```dts
type RemoteCommand<Input, Output> = {
	(
		arg: undefined extends Input ? Input | void : Input
	): Promise<Output> & {
		updates(
			...updates: RemoteQueryUpdate[]
		): Promise<Output>;
	};
	/** The number of pending command executions */
	get pending(): number;
};
```

</div>

## RemoteForm

The type of a remote `form` function. See [Remote functions](/docs/kit/remote-functions#form) for full documentation.

<div class="ts-block">

```dts
type RemoteForm<
	Input extends RemoteFormInput | void,
	Output
> = {
	/** Attachment that sets up an event handler that intercepts the form submission on the client to prevent a full page reload */
	[attachment: symbol]: (node: HTMLFormElement) => void;
	method: 'POST';
	/** The URL to send the form to. */
	action: string;
	/** The `<form>` element this instance is currently attached to, if any. */
	get element(): HTMLFormElement | null;
	/** Submit the currently attached form programmatically. */
	submit(): Promise<boolean> & {
		updates: (
			...updates: RemoteQueryUpdate[]
		) => Promise<boolean>;
	};
	/** Use the `enhance` method to influence what happens when the form is submitted. */
	enhance(
		callback: RemoteFormEnhanceCallback<Input, Output>
	): {
		method: 'POST';
		action: string;
		[attachment: symbol]: (node: HTMLFormElement) => void;
	};
	/**
	 * Create an instance of the form for the given `id`.
	 * The `id` is stringified and used for deduplication to potentially reuse existing instances.
	 * Useful when you have multiple forms that use the same remote form action, for example in a loop.
	 * ```svelte
	 * {#each todos as todo}
	 *	{const todoForm = updateTodo.for(todo.id)}
	 *	<form {...todoForm}>
	 *		{#if todoForm.result?.invalid}<p>Invalid data</p>{/if}
	 *		...
	 *	</form>
	 *	{/each}
	 * ```
	 */
	for(
		id: ExtractId<Input>
	): Omit<RemoteForm<Input, Output>, 'for'>;
	/** Preflight checks */
	preflight(
		schema: StandardSchemaV1<Input, any>
	): RemoteForm<Input, Output>;
	/** Validate the form contents programmatically */
	validate(options?: {
		/**
		 * Set this to `true` to also show validation issues of fields that haven't yet been
		 * edited and blurred. This option is ignored for forms that have previously been
		 * submitted, in which case all fields are always subject to validation
		 * (unless the form is reset, at which point it is treated as pristine)
		 */
		all?: boolean;
		/** Set this to `true` to only run the `preflight` validation. */
		preflightOnly?: boolean;
	}): Promise<void>;
	/** The result of the form submission */
	get result(): Output | undefined;
	/** The number of pending submissions */
	get pending(): number;
	/** True if the form has been submitted at least once, and hasn't been reset since */
	get submitted(): boolean;
	/** Access form fields using object notation */
	fields: RemoteFormFieldsRoot<Input>;
};
```

</div>

## RemoteFormEnhanceCallback

The callback passed to a remote form's `enhance` method. See [Remote functions](/docs/kit/remote-functions#form) for full documentation.

<div class="ts-block">

```dts
type RemoteFormEnhanceCallback<
	Input extends RemoteFormInput | void =
		RemoteFormInput | void,
	Output = any
> = (
	form: RemoteFormEnhanceInstance<Input, Output>
) => MaybePromise<void>;
```

</div>

## RemoteFormEnhanceInstance

The form instance as received inside an `enhance` callback. See [Remote functions](/docs/kit/remote-functions#form) for full documentation.

<div class="ts-block">

```dts
type RemoteFormEnhanceInstance<
	Input extends RemoteFormInput | void =
		RemoteFormInput | void,
	Output = any
> = Omit<
	RemoteForm<Input, Output>,
	'enhance' | 'element'
> & {
	readonly element: HTMLFormElement;
};
```

</div>

## RemoteFormField

Form field accessor type that provides name(), value(), and issues() methods

<div class="ts-block">

```dts
type RemoteFormField<Value extends RemoteFormFieldValue> =
	RemoteFormFieldMethods<Value> & {
		/**
		 * Returns an object that can be spread onto an input element with the correct type attribute,
		 * aria-invalid attribute if the field is invalid, and appropriate value/checked property getters/setters.
		 * @example
		 * ```svelte
		 * <input {...myForm.fields.myString.as('text')} />
		 * <input {...myForm.fields.myNumber.as('number')} />
		 * <input {...myForm.fields.myBoolean.as('checkbox')} />
		 * ```
		 */
		as<T extends RemoteFormFieldType<Value>>(
			...args: AsArgs<T, Value>
		): InputElementProps<T>;
	};
```

</div>

## RemoteFormFieldType

<div class="ts-block">

```dts
type RemoteFormFieldType<T> = {
	[K in keyof InputTypeMap]: T extends InputTypeMap[K]
		? K
		: never;
}[keyof InputTypeMap];
```

</div>

## RemoteFormFieldValue

<div class="ts-block">

```dts
type RemoteFormFieldValue =
	| string
	| string[]
	| number
	| boolean
	| File
	| File[];
```

</div>

## RemoteFormFields

Recursive type to build form fields structure with proxy access

<div class="ts-block">

```dts
type RemoteFormFields<T> =
	WillRecurseIndefinitely<T> extends true
		? RecursiveFormFields
		: NonNullable<T> extends
					| string
					| number
					| boolean
					| File
			? RemoteFormField<NonNullable<T>>
			: // [NonNullable<T>] is used to prevent distributing over union while still allowing
				// nullable wrappers (e.g. `string[] | undefined` from a schema with `.default([])`)
				// to be treated as arrays; only the last condition should distribute over unions
				[NonNullable<T>] extends [string[] | File[]]
				? RemoteFormField<NonNullable<T>> & {
						[K in number]: RemoteFormField<
							NonNullable<T>[number]
						>;
					}
				: [NonNullable<T>] extends [Array<infer U>]
					? RemoteFormFieldContainer<NonNullable<T>> & {
							[K in number]: RemoteFormFields<U>;
						}
					: RemoteFormFieldContainer<T> & {
							[K in KeysOfUnion<T>]-?: RemoteFormFields<
								ValueOfUnionKey<T, K>
							>;
						};
```

</div>

## RemoteFormInput

<div class="ts-block">

```dts
interface RemoteFormInput {/*…*/}
```

<div class="ts-block-property">

```dts
[key: string]: MaybeArray<string | number | boolean | File | RemoteFormInput> | undefined;
```

<div class="ts-block-property-details"></div>
</div></div>

## RemoteFormIssue

<div class="ts-block">

```dts
interface RemoteFormIssue {/*…*/}
```

<div class="ts-block-property">

```dts
message: string;
```

<div class="ts-block-property-details"></div>
</div>

<div class="ts-block-property">

```dts
path: Array<string | number>;
```

<div class="ts-block-property-details"></div>
</div></div>

## RemoteLiveQuery

<div class="ts-block">

```dts
type RemoteLiveQuery<T> = RemoteResource<T> &
	AsyncIterable<T> & {
		/** `true` if the live stream is currently connected. */
		readonly connected: boolean;
		/** `true` once the current live stream iterator is done. */
		readonly done: boolean;
		/** Reconnects the live stream immediately. */
		reconnect(): Promise<void>;
	};
```

</div>

## RemoteLiveQueryFunction

The type of a remote `query.live` function. See [Remote functions](/docs/kit/remote-functions#query.live) for full documentation.

The optional `Validated` generic parameter represents the argument type *after* the
query's schema has validated and (optionally) transformed it, and matches the type
yielded by [`requested`](/docs/kit/$app-server#requested).

<div class="ts-block">

```dts
type RemoteLiveQueryFunction<
	Input,
	Output,
	_Validated = Input
> = (
	arg: undefined extends Input ? Input | void : Input
) => RemoteLiveQuery<Output>;
```

</div>

## RemotePrerenderFunction

The type of a remote `prerender` function. See [Remote functions](/docs/kit/remote-functions#prerender) for full documentation.

<div class="ts-block">

```dts
type RemotePrerenderFunction<Input, Output> = (
	arg: undefined extends Input ? Input | void : Input
) => RemoteResource<Output>;
```

</div>

## RemoteQuery

<div class="ts-block">

```dts
type RemoteQuery<T> = RemoteResource<T> & {
	/**
	 * On the client, this function will update the value of the query without re-fetching it.
	 *
	 * On the server, this can be called in the context of a `command` or `form` and the specified data will accompany the action response back to the client.
	 * This prevents SvelteKit needing to refresh all queries on the page in a second server round-trip.
	 */
	set(value: T): void;
	/**
	 * On the client, this function will re-fetch the query from the server.
	 *
	 * On the server, this can be called in the context of a `command` or `form` and the refreshed data will accompany the action response back to the client.
	 * This prevents SvelteKit needing to refresh all queries on the page in a second server round-trip.
	 */
	refresh(): Promise<void>;
	/**
	 * Temporarily override a query's value during a [single-flight mutation](https://svelte.dev/docs/kit/remote-functions#Single-flight-mutations) to provide optimistic updates.
	 *
	 * ```svelte
	 * <script>
	 *   import { getTodos, addTodo } from './todos.remote.js';
	 *   const todos = getTodos();
	 * </script>
	 *
	 * <form {...addTodo.enhance(async (form) => {
	 *   await form.submit().updates(
	 *     todos.withOverride((todos) => [...todos, { text: form.fields.text.value() }])
	 *   );
	 * })}>
	 *   <input type="text" name="text" />
	 *   <button type="submit">Add Todo</button>
	 * </form>
	 * ```
	 */
	withOverride(
		update: (current: T) => T
	): RemoteQueryOverride;
};
```

</div>

## RemoteQueryFunction

The return value of a remote `query` function. See [Remote functions](/docs/kit/remote-functions#query) for full documentation.

The optional `Validated` generic parameter represents the argument type *after* the
query's schema has validated and (optionally) transformed it — this is the type the
query's implementation function receives on the server, and the type yielded by
[`requested`](/docs/kit/$app-server#requested). For queries declared
with [Standard Schema](https://standardschema.dev/) it differs from `Input` when the
schema contains a transform (e.g. `v.pipe(v.number(), v.transform(String))` has
`Input = number` but `Validated = string`). For `'unchecked'` validators and queries
without arguments it defaults to `Input`.

<div class="ts-block">

```dts
type RemoteQueryFunction<
	Input,
	Output,
	_Validated = Input
> = (
	arg: undefined extends Input ? Input | void : Input
) => RemoteQuery<Output>;
```

</div>

## RemoteQueryOverride

<div class="ts-block">

```dts
type RemoteQueryOverride = () => void;
```

</div>

## RemoteQueryUpdate

<div class="ts-block">

```dts
type RemoteQueryUpdate =
	| RemoteQuery<any>
	| RemoteLiveQuery<any>
	| RemoteQueryFunction<any, any>
	| RemoteLiveQueryFunction<any, any>
	| RemoteQueryOverride;
```

</div>

## RemoteResource

<div class="ts-block">

```dts
type RemoteResource<T> = Promise<T> & {
	/** The error in case the query fails. */
	get error(): App.Error | undefined;
	/** `true` before the first result is available and during refreshes */
	get loading(): boolean;
} & (
		| {
				/** The current value of the query. Undefined until `ready` is `true` */
				get current(): undefined;
				ready: false;
		  }
		| {
				/** The current value of the query. Undefined until `ready` is `true` */
				get current(): T;
				ready: true;
		  }
	);
```

</div>

## RequestedEntry

A single entry yielded by [`requested`](/docs/kit/$app-server#requested)
when called with a regular `query`. `arg` is the validated argument (the input *after*
the query's schema validated and transformed it, if applicable); `query` is a
`RemoteQuery` bound to the client's original cache key, so `refresh()` / `set()` will
update the correct client entry.

<div class="ts-block">

```dts
type RequestedEntry<Validated, Output> = {
	arg: Validated;
	query: RemoteQuery<Output>;
};
```

</div>

## RequestedResult

<div class="ts-block">

```dts
type RequestedResult<Validated, Output> =
	| QueryRequestedResult<Validated, Output>
	| LiveQueryRequestedResult<Validated, Output>;
```

</div>

## ValidationError

A validation error thrown by `invalid`.

<div class="ts-block">

```dts
interface ValidationError {/*…*/}
```

<div class="ts-block-property">

```dts
issues: StandardSchemaV1.Issue[];
```

<div class="ts-block-property-details">

The validation issues

</div>
</div></div>