Server Actions | blade47/next.js Wiki | doc0

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Server Actions | blade47/next.js Wiki | doc0

Form Property / Attribute	Disallowed in `<Form>`	Purpose / Handling
`method`	Yes (`DISALLOWED_FORM_PROPS`)	Disallowed directly on `<Form>`; only `get` method is supported for navigating forms.
`encType`	Yes (`DISALLOWED_FORM_PROPS`)	Disallowed directly on `<Form>`; only `application/x-www-form-urlencoded` is supported.
`target`	Yes (`DISALLOWED_FORM_PROPS`)	Disallowed directly on `<Form>`; only `_self` target is supported.

Utility Function	Parameters	Return Type	Purpose / Description
`arrayBufferToString`	`buffer: ArrayBuffer \| Uint8Array`	`string`	Converts byte buffers to binary strings, handling V8's 65,535 argument limit via `String.fromCharCode` batching or iteration.
`stringToUint8Array`	`binary: string`	`Uint8Array`	Converts a binary string into a `Uint8Array` using character codes.
`encrypt`	`key: CryptoKey, iv: Uint8Array, data: Uint8Array`	`Promise<ArrayBuffer>`	Encrypts data using `crypto.subtle.encrypt` with the `AES-GCM` algorithm.
`decrypt`	`key: CryptoKey, iv: Uint8Array, data: Uint8Array`	`Promise<ArrayBuffer>`	Decrypts data using `crypto.subtle.decrypt` with the `AES-GCM` algorithm.
`getActionEncryptionKey`	None	`Promise<CryptoKey>`	Resolves the encryption key from `NEXT_SERVER_ACTIONS_ENCRYPTION_KEY` or `serverActionsManifest.encryptionKey`, importing it via `crypto.subtle.importKey`.

Request Metadata Property	Condition / Check	Purpose / Description
`actionId`	`req.headers.get(ACTION_HEADER)` or `req.headers[ACTION_HEADER]`	Extracts the target server action identifier from headers.
`isURLEncodedAction`	`req.method === 'POST' && contentType === 'application/x-www-form-urlencoded'`	Identifies URL-encoded POST actions (which later bail out in the action handler).
`isMultipartAction`	`req.method === 'POST' && contentType?.startsWith('multipart/form-data')`	Identifies multipart form data submissions carrying action payloads.
`isFetchAction`	`actionId !== undefined && typeof actionId === 'string' && req.method === 'POST'`	Identifies fetch-based action requests carrying a valid action header.
`isPossibleServerAction`	`isFetchAction \|\| isURLEncodedAction \|\| isMultipartAction`	Aggregate boolean indicating whether the request should enter action routing.

Phase Property / Hook	Target Store / Function	Purpose and Behavior
`requestStore.phase`	`'action'` transitioning to `'render'`	Switches the execution context mode when shifting from userspace action execution to subsequent page rendering.
Cookie Synchronization	`synchronizeMutableCookies(requestStore)`	Updates immutable cookies in the render phase to reflect mutations performed via `cookies()` during the action phase.
Draft Mode State	`workStore.isDraftMode`	Reflects toggles to draft mode performed in `requestStore.draftMode.isEnabled` for subsequent rendering.
Tag/Path Revalidation	`executeRevalidates(workStore)`	Ensures all pending data revalidations called by `revalidateTag` or `revalidatePath` take effect before rendering.

export function getFlightStream<T>(
  flightStream: Readable | BinaryStreamOf<T>,
  debugStream: Readable | ReadableStream<Uint8Array> | undefined,
  debugEndTime: number | undefined,
  nonce: string | undefined
): Promise<T>

Payload Type Constant	Value	Role in Stream Ingestion
`INLINE_FLIGHT_PAYLOAD_BOOTSTRAP`	`0`	Initializes the `self.__next_f` chunk array instruction queue.
`INLINE_FLIGHT_PAYLOAD_DATA`	`1`	Enqueues standard string-encoded Flight data chunks.
`INLINE_FLIGHT_PAYLOAD_FORM_STATE`	`2`	Serializes form state states alongside initial boot instructions.
`INLINE_FLIGHT_PAYLOAD_BINARY`	`3`	Encodes arbitrary binary chunk buffers in base64 format for safe script tag embedding.

Revalidation Constant	Value / Type	Meaning and Behavior
`ActionDidNotRevalidate`	`0`	Indicates the server action triggered no data mutations or revalidations.
`ActionDidRevalidateDynamicOnly`	`1`	Indicates revalidation was restricted to dynamic data sources.
`ActionDidRevalidateStaticAndDynamic`	`2`	Indicates both static and dynamic cache entries must be invalidated.

Design Choice	Benefit	Cost
Lazy cache eviction via version increments (`currentRouteCacheVersion++`)	Avoids expensive synchronous garbage collection sweeps across all active entries upon revalidation.	Stale entries remain in memory until actively read and evicted.
Single global set for `invalidationListeners`	Low memory overhead and simple registration model when no granular path-based tags exist.	Scans all registered tasks on invalidation rather than filtering by affected segments.
Clearing `onInvalidate` callbacks immediately upon invocation	Guarantees user-space listeners execute at most once per invalidation event.	Requires tasks to re-register listeners if subsequent invalidations need tracking.

Field Name	Type	Description
`actionId`	`string`	Unique identifier corresponding to the server reference key in the manifest.
`runtime`	`string`	Execution environment target, resolved as either `'node'` or `'edge'`.
`filename`	`string`	Absolute or relative source file path containing the action definition.
`functionName`	`string`	Exported JavaScript function name, or `'inline server action'` if prefixed with `$$RSC_SERVER_ACTION_`.