`CanWriteCell`

The CanWriteCell type describes a function that decides whether a client may write a given Cell on a path of a WsServer.

(
  pathId: Id,
  tableId: Id,
  rowId: Id,
  cellId: Id,
  cell: CellOrUndefined,
  context: {[key: string]: any} | undefined,
): boolean

	Type	Description
`pathId`	`Id`	The `Id` of the path.
`tableId`	`Id`	The `Id` of the `Table`.
`rowId`	`Id`	The `Id` of the `Row`.
`cellId`	`Id`	The `Id` of the `Cell`.
`cell`	`CellOrUndefined`	The new value of the `Cell`, or `undefined` if it is being deleted.
`context`	`{[key: string]: any} \| undefined`	The context from the client's `ClientAccess`.
returns	`boolean`	Whether the client may write the `Cell`.

It is called for each Cell in the changes that a writable client sends to the server, including deletions, where the cell parameter is undefined. It must be synchronous. Cells for which it returns false are neither merged into the path's MergeableStore nor relayed to other clients.

If the rejected change was newer than the server's own version of that Cell, and different from it, the server sends that client alone its own version (or a deletion, if it has none), stamped just after the rejected change. The client is brought back into line with the server, rather than silently diverging from it, and nothing changes on the server or for any other client.

This function decides only about Cells. Unless you also provide a CanWriteValue function, every writable client may write any Value. And unless you provide an Authorize function, every client is admitted as writable, with an undefined context.

Since

v10.1.0