[y sweet] support optional initialClientToken for YSweetProvider (#319)

This updates the `YSweetProvider` (and the React `<YDocProvider>`) to
take an optional `initialClientToken`. This can be used to cut out one
server roundtrip if the client token is obtained at render time.

js-pkg/client/src/provider.ts

@@ -224,6 +224,7 @@ export type YSweetProviderParams = {
   resyncInterval?: number
   maxBackoffTime?: number
   disableBc?: boolean
+  initialClientToken?: ClientToken
 }
 
 /**
@@ -526,8 +527,10 @@ export async function ySweetProviderWrapper(
   authEndpoint: AuthEndpoint,
   roomname: string,
   doc: Y.Doc,
-  providerParams: YSweetProviderParams = {},
+  wrapperParams: YSweetProviderParams = {},
 ): Promise<YSweetProviderWithClientToken> {
+  let { initialClientToken, ...providerParams } = wrapperParams
+
   // we use an observable that lives outside the provider to store event listeners
   // so that we can re-subscribe to events when the provider is re-created
   const observable = new Observable<string>()
@@ -538,7 +541,7 @@ export async function ySweetProviderWrapper(
   const awareness = providerParams.awareness ?? new awarenessProtocol.Awareness(doc)
   providerParams = { ...providerParams, awareness }
 
-  let _clientToken = await getClientToken(authEndpoint, roomname)
+  let _clientToken = initialClientToken ?? (await getClientToken(authEndpoint, roomname))
   let _provider = new YSweetProvider(_clientToken.url, roomname, doc, {
     ...updateProviderParams(providerParams, _clientToken),
   })

js-pkg/react/src/main.tsx

@@ -7,6 +7,7 @@ import {
   debuggerUrl,
 } from '@y-sweet/client'
 import type { AuthEndpoint, YSweetProviderWithClientToken } from '@y-sweet/client'
+import type { ClientToken } from '@y-sweet/sdk'
 import type { ReactNode } from 'react'
 import { createContext, useCallback, useContext, useEffect, useMemo, useState } from 'react'
 import type { Awareness } from 'y-protocols/awareness'
@@ -171,22 +172,26 @@ export type YDocProviderProps = {
   /** The children to render. */
   children: ReactNode
 
-  /** Response of a `getConnectionKey` call, passed from server to client. */
+  /** The doc id to use for the Y.Doc. */
   docId: string
 
-  /** The endpoint to use for authentication. */
+  /** The endpoint to use for authentication or an async function that returns a client token. */
   authEndpoint: AuthEndpoint
 
+  /** An optional initial client token to use for the Y.Doc. This will be used initially, and if
+   * the client token expires, the `authEndpoint` will be called to get a new client token. */
+  initialClientToken?: ClientToken
+
   /** If set to a string, the URL query parameter with this name
-   * will be set to the doc id from connectionKey. */
+   * will be set to the doc id provided. */
   setQueryParam?: string
 }
 
 /**
  * A React component that provides a Y.Doc instance to its children given an auth endpoint and a doc id.
  */
 export function YDocProvider(props: YDocProviderProps) {
-  const { children, docId, authEndpoint } = props
+  const { children, docId, authEndpoint, initialClientToken } = props
 
   const [ctx, setCtx] = useState<YjsContextType | null>(null)
 
@@ -197,6 +202,7 @@ export function YDocProvider(props: YDocProviderProps) {
 
     ;(async () => {
       provider = await createYjsProvider(doc, docId, authEndpoint, {
+        initialClientToken,
         // TODO: this disables local cross-tab communication, which makes
         // debugging easier, but should be re-enabled eventually
         disableBc: true,