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@atlaskit/editor-plugin-collab-edit

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Collab Edit plugin for @atlaskit/editor-core

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import type { Transaction } from '@atlaskit/editor-prosemirror/state'; /** * Upper bound on how long the send may stay held, measured from the transaction that *started* the * hold rather than the most recent one. * * This is the only time bound on the hold. Producers decide when to release on semantic grounds — * a completed block, the end of a stream — and this bounds how long that can take. It therefore * doubles as the guarantee that a producer which never releases, because it aborted or threw * between hold and release, cannot stop the editor sending for the rest of the session. */ export declare const MAX_SEND_HOLD_MS = 2000; export type CollabSendHold = { /** * Whether the flush is currently held. Reads the clock, so a hold that has outlived * {@link MAX_SEND_HOLD_MS} reports as released without needing a transaction to clear it. */ isHeld: (now?: number) => boolean; /** * Feed every transaction through this. Transactions that carry no {@link DEFER_COLLAB_SEND} * metadata leave the hold untouched — that is the whole point of the hold being sticky rather * than per-transaction. */ observe: (transaction: Readonly<Transaction>, now?: number) => void; }; /** * Tracks whether sending to the collab service is currently held back. * * A producer that streams into the document needs several of its transactions to accumulate in the * unconfirmed queue before anything is sent, so they can be composed into one step. Marking only * the producer's own transactions is not enough: `sendTransaction` runs for *every* state update, * and `provider.send` flushes and locks the entire queue regardless of which transaction triggered * it. Acknowledgements from previous commits, remote steps, selection changes and the user's own * typing all trigger it. * * So the hold has to be a state that spans transactions rather than a flag on one: * * - `tr.setMeta(DEFER_COLLAB_SEND, true)` starts the hold, and does *not* extend one already in * progress * - `tr.setMeta(DEFER_COLLAB_SEND, false)` releases it * - anything else leaves it as it is * * Not extending matters. A producer marks every frame it wants held, so re-arming on each one * would push the deadline back indefinitely and the bound would never be reached during an active * stream. Measuring from the first held transaction instead makes the hold flush at least every * {@link MAX_SEND_HOLD_MS}, with the next held frame starting a fresh window. * * While held, nothing is sent. Note this includes the local user's own edits: `sendableSteps` * returns the queue in version order, so there is no way to send a step that sits behind held * steps. Producers should keep hold windows short for that reason. */ export declare const createCollabSendHold: () => CollabSendHold;