Gumnut Document

The GumnutDoc class represents a document in Gumnut that can contain multiple nodes, and is the primary way to connect and interact with Gumnut. It provides methods for managing the document, accessing nodes, and monitoring changes.

A document in Gumnut is analogous to a form in a normal web app. It contains multiple nodes (fields), that contain different types of data and can be edited by different users.

Import

Create a GumnutDoc instance by calling connectToGumnutDoc().

import { connectToGumnutDoc } from '@gumnutdev/api';

const api = connectToGumnutDoc({ docId: 'document-id', getToken: ... });
const { doc, shutdown } = api;

Properties

Property	Type	Description
projectId	string	The ID of the project that contains this document
docId	string	The ID of this document
ready	Promise<void>	A promise that resolves when the document is ready for use
dataFrom	Date	When was the data here from. This may be from your backend, or it may be as a result of a commit
isShutdown	boolean	Whether this doc is dead/shutdown and should be recreated
error	string|Error|undefined	Any error state currently reported
actions	GumnutDocActions	Contains methods for loading, reverting, and committing document changes

Methods

useNode(node)

Gets a reference to a node within the document. If the node doesn't exist, it will be created automatically when data is written to it.

const textNode = doc.useNode("text-content");

Parameter	Type	Description
node	string	The ID of the node to access

Returns

Returns a GumnutNode instance representing the requested node.

Example

// Access a text node
const mainText = doc.useNode("main-text");

// Access a data node
const settingsNode = doc.useNode("settings");

nodes()

Returns an iterable of all node IDs in the document.

const nodeIds = doc.nodes();

Returns

Returns an Iterable<string> containing all the node IDs.

Example

// List all nodes in the document
for (const nodeId of doc.nodes()) {
  console.log(`Node: ${nodeId}`);
}

actions.commit()

Requests that the server create a snapshot of the current document state, while giving you a chance to write them to your own backend. This can be useful to ensure all changes are persisted.

doc.actions.commit(async ({ changes, all }) => {
  // TODO: write your changes to your own backend here
  // if this throws, no Gumnut snapshot will be taken
  // 'changes' contains only the dirty nodes
  // 'all' contains all nodes
});

Example

// Handle a "save" button
saveButton.addEventListener("click", async () => {
  await doc.actions.commit(async ({ changes }) => {
    await saveToYourDatabase("your-document-id", changes);
  });
});

actions.load(nodes, opts)

Instructs Gumnut to load canonical data into the document.

doc.actions.load({ "node-id": "node value" }, { from: new Date() });

Parameter	Type	Description
nodes	Record<string, string>	Object mapping node IDs to their values
opts	{ from: Date }	Options with the timestamp when this data was in your database

actions.revertAll()

Reverts all changes to the canonical data, clearing all dirty fields.

doc.actions.revertAll();

userForClientId(clientId)

Read the user information for a given client ID.

const userInfo = doc.userForClientId("client-123");

Parameter	Type	Description
clientId	string	The client ID to get user information for

Returns

Returns a UserInfo object containing the user's ID and profile information, or undefined if the client ID is not found.

clients()

Take a snapshot of the current clients connected to this document.

const clientIds = doc.clients();

Returns

Returns an Iterable<string> containing all the client IDs.

pending()

Returns a Promise that resolves when the state of the document is completely sent off to the server.

await doc.pending();

addListener(type, cb, signal)

Adds a listener for various events.

doc.addListener(type, callback, signal);

Parameter	Type	Description
type	'error'|'ready'|'clients'	The type of the event to listen to
cb	Function	Callback function to invoke when something changes
signal	AbortSignal	Signal to control the lifecycle of the listener

Event Types

• error: Dispatched if an error occurs while running this document. The callback receives (error: string | Error) => void.
• ready: Dispatched when the document is ready. This may happen more than once if you're disconnected from the server. The callback receives () => void.
• clients: Dispatched when the set of clients connected to the document changes. The callback receives (delta: ReadonlyMap<string, boolean>) => void.

Example

const controller = new AbortController();

doc.addListener(
  "clients",
  (delta) => {
    console.log("The current set of clients here is", doc.clients());
    console.log("Client changes:", delta);
  },
  controller.signal
);

// Later, to remove the listener
controller.abort();