feat(sanity): add release layering foundations

packages/sanity/src/core/preview/utils/getPreviewStateObservable.ts

@@ -1,16 +1,26 @@
 import {type PreviewValue, type SanityDocument, type SchemaType} from '@sanity/types'
+import {omit} from 'lodash'
 import {type ReactNode} from 'react'
-import {combineLatest, type Observable, of} from 'rxjs'
-import {map, startWith} from 'rxjs/operators'
+import {combineLatest, from, type Observable, of} from 'rxjs'
+import {map, mergeMap, scan, startWith} from 'rxjs/operators'
+import {type PreparedSnapshot} from 'sanity'
 
 import {getDraftId, getPublishedId, getVersionId} from '../../util/draftUtils'
 import {type DocumentPreviewStore} from '../documentPreviewStore'
 
+/**
+ * @internal
+ */
+export type VersionsRecord = Record<string, PreparedSnapshot>
+
+type VersionTuple = [bundleId: string, snapshot: PreparedSnapshot]
+
 export interface PreviewState {
   isLoading?: boolean
   draft?: PreviewValue | Partial<SanityDocument> | null
   published?: PreviewValue | Partial<SanityDocument> | null
   version?: PreviewValue | Partial<SanityDocument> | null
+  versions: VersionsRecord
 }
 
 const isLiveEditEnabled = (schemaType: SchemaType) => schemaType.liveEdit === true
@@ -25,31 +35,70 @@ export function getPreviewStateObservable(
   schemaType: SchemaType,
   documentId: string,
   title: ReactNode,
-  perspective?: string,
+  perspective: {
+    bundleIds: string[]
+    bundleStack: string[]
+  } = {
+    bundleIds: [],
+    bundleStack: [],
+  },
 ): Observable<PreviewState> {
   const draft$ = isLiveEditEnabled(schemaType)
     ? of({snapshot: null})
     : documentPreviewStore.observeForPreview({_id: getDraftId(documentId)}, schemaType)
 
-  const version$ = perspective
-    ? documentPreviewStore.observeForPreview(
-        {_id: getVersionId(documentId, perspective)},
-        schemaType,
-      )
-    : of({snapshot: null})
+  const versions$ = from(perspective.bundleIds).pipe(
+    mergeMap<string, Observable<VersionTuple>>((bundleId) =>
+      documentPreviewStore
+        .observeForPreview({_id: getVersionId(documentId, bundleId)}, schemaType)
+        .pipe(map((storeValue) => [bundleId, storeValue])),
+    ),
+    scan<VersionTuple, VersionsRecord>((byBundleId, [bundleId, value]) => {
+      if (value.snapshot === null) {
+        return omit({...byBundleId}, [bundleId])
+      }
+
+      return {
+        ...byBundleId,
+        [bundleId]: value,
+      }
+    }, {}),
+    startWith<VersionsRecord>({}),
+  )
+
+  // Iterate the release stack in descending precedence, returning the highest precedence existing
+  // version document.
+  const version$ = versions$.pipe(
+    map((versions) => {
+      for (const bundleId of perspective.bundleStack) {
+        if (bundleId in versions) {
+          return versions[bundleId]
+        }
+      }
+      return {snapshot: null}
+    }),
+    startWith<PreparedSnapshot>({snapshot: null}),
+  )
 
   const published$ = documentPreviewStore.observeForPreview(
     {_id: getPublishedId(documentId)},
     schemaType,
   )
 
-  return combineLatest([draft$, published$, version$]).pipe(
-    map(([draft, published, version]) => ({
+  return combineLatest([draft$, published$, version$, versions$]).pipe(
+    map(([draft, published, version, versions]) => ({
       draft: draft.snapshot ? {title, ...(draft.snapshot || {})} : null,
       isLoading: false,
       published: published.snapshot ? {title, ...(published.snapshot || {})} : null,
       version: version.snapshot ? {title, ...(version.snapshot || {})} : null,
+      versions,
     })),
-    startWith({draft: null, isLoading: true, published: null, version: null}),
+    startWith({
+      draft: null,
+      isLoading: true,
+      published: null,
+      version: null,
+      versions: {},
+    }),
   )
 }

packages/sanity/src/core/store/_legacy/datastores.ts

@@ -4,6 +4,7 @@ import {useTelemetry} from '@sanity/telemetry/react'
 import {useCallback, useMemo} from 'react'
 import {of} from 'rxjs'
 
+import {useRouter} from '../../../router'
 import {useClient, useSchema, useTemplates} from '../../hooks'
 import {createDocumentPreviewStore, type DocumentPreviewStore} from '../../preview'
 import {useAddonDataset, useSource, useWorkspace} from '../../studio'
@@ -299,26 +300,29 @@ export function useBundlesStore(): BundlesStore {
   const currentUser = useCurrentUser()
   const addonDataset = useAddonDataset()
   const studioClient = useClient(DEFAULT_STUDIO_CLIENT_OPTIONS)
+  const router = useRouter()
 
+  // TODO: Include hidden layers state.
   return useMemo(() => {
     const bundlesStore =
       resourceCache.get<BundlesStore>({
-        dependencies: [workspace, addonDataset, currentUser],
+        dependencies: [workspace, addonDataset, currentUser, router.perspectiveState],
         namespace: 'BundlesStore',
       }) ||
       createBundlesStore({
         addonClient: addonDataset.client,
         addonClientReady: addonDataset.ready,
         studioClient,
         currentUser,
+        perspective: router.perspectiveState.perspective,
       })
 
     resourceCache.set({
-      dependencies: [workspace, addonDataset, currentUser],
+      dependencies: [workspace, addonDataset, currentUser, router.perspectiveState],
       namespace: 'BundlesStore',
       value: bundlesStore,
     })
 
     return bundlesStore
-  }, [resourceCache, workspace, addonDataset, studioClient, currentUser])
+  }, [resourceCache, workspace, addonDataset, currentUser, router.perspectiveState, studioClient])
 }

packages/sanity/src/core/store/bundles/createBundlesStore.ts

@@ -55,6 +55,7 @@ const INITIAL_STATE: bundlesReducerState = {
   bundles: new Map(),
   deletedBundles: {},
   state: 'initialising',
+  releaseStack: [],
 }
 
 const NOOP_BUNDLE_STORE: BundlesStore = {
@@ -69,6 +70,7 @@ const LOADED_BUNDLE_STORE: BundlesStore = {
       bundles: new Map(),
       deletedBundles: {},
       state: 'loaded' as const,
+      releaseStack: [],
     }),
   ),
   getMetadataStateForSlugs$: () => of({data: null, error: null, loading: false}),
@@ -88,6 +90,7 @@ export function createBundlesStore(context: {
   studioClient: SanityClient | null
   addonClientReady: boolean
   currentUser: User | null
+  perspective?: string
 }): BundlesStore {
   const {addonClient, studioClient, addonClientReady, currentUser} = context
 
@@ -251,7 +254,7 @@ export function createBundlesStore(context: {
 
   const state$ = merge(listFetch$, listener$, dispatch$).pipe(
     filter((action): action is bundlesReducerAction => typeof action !== 'undefined'),
-    scan((state, action) => bundlesReducer(state, action), INITIAL_STATE),
+    scan((state, action) => bundlesReducer(state, action, context.perspective), INITIAL_STATE),
     startWith(INITIAL_STATE),
     shareReplay(1),
   )

packages/sanity/src/core/store/bundles/reducer.ts

@@ -1,3 +1,5 @@
+import {DRAFTS_FOLDER, resolveBundlePerspective} from 'sanity'
+
 import {type BundleDocument} from './types'
 
 interface BundleDeletedAction {
@@ -42,6 +44,12 @@ export interface bundlesReducerState {
   deletedBundles: Record<string, BundleDocument>
   state: 'initialising' | 'loading' | 'loaded' | 'error'
   error?: Error
+
+  /**
+   * An array of release ids ordered chronologically to represent the state of documents at the
+   * given point in time.
+   */
+  releaseStack: string[]
 }
 
 function createBundlesSet(bundles: BundleDocument[] | null) {
@@ -54,6 +62,7 @@ function createBundlesSet(bundles: BundleDocument[] | null) {
 export function bundlesReducer(
   state: bundlesReducerState,
   action: bundlesReducerAction,
+  perspective?: string,
 ): bundlesReducerState {
   switch (action.type) {
     case 'LOADING_STATE_CHANGED': {
@@ -71,6 +80,10 @@ export function bundlesReducer(
       return {
         ...state,
         bundles: bundlesById,
+        releaseStack: getReleaseStack({
+          bundles: bundlesById,
+          perspective,
+        }),
       }
     }
 
@@ -82,6 +95,10 @@ export function bundlesReducer(
       return {
         ...state,
         bundles: currentBundles,
+        releaseStack: getReleaseStack({
+          bundles: currentBundles,
+          perspective,
+        }),
       }
     }
 
@@ -105,6 +122,7 @@ export function bundlesReducer(
         ...state,
         bundles: currentBundles,
         deletedBundles: nextDeletedBundles,
+        releaseStack: [...state.releaseStack].filter((id) => id !== deletedBundleId),
       }
     }
 
@@ -117,10 +135,49 @@ export function bundlesReducer(
       return {
         ...state,
         bundles: currentBundles,
+        releaseStack: getReleaseStack({
+          bundles: currentBundles,
+          perspective,
+        }),
       }
     }
 
     default:
       return state
   }
 }
+
+function getReleaseStack({
+  bundles,
+  perspective,
+}: {
+  bundles?: Map<string, BundleDocument>
+  perspective?: string
+}): string[] {
+  if (typeof bundles === 'undefined') {
+    return []
+  }
+
+  // TODO: Handle system perspectives.
+  if (!perspective?.startsWith('bundle.')) {
+    return []
+  }
+
+  const stack = [...bundles.values()]
+    .toSorted(sortReleases(resolveBundlePerspective(perspective)))
+    .map(({_id}) => _id)
+    .concat(DRAFTS_FOLDER)
+
+  return stack
+}
+
+// TODO: Implement complete layering heuristics.
+function sortReleases(perspective?: string): (a: BundleDocument, b: BundleDocument) => number {
+  return function (a, b) {
+    // Ensure the current release takes highest precedence.
+    if (a._id === perspective) {
+      return -1
+    }
+    return 0
+  }
+}

packages/sanity/src/core/store/bundles/useBundles.ts

@@ -7,10 +7,17 @@ import {type BundleDocument} from './types'
 
 interface BundlesState {
   data: BundleDocument[] | null
+  bundles: Map<string, BundleDocument>
   deletedBundles: Record<string, BundleDocument>
   error?: Error
   loading: boolean
   dispatch: React.Dispatch<bundlesReducerAction>
+
+  /**
+   * An array of release ids ordered chronologically to represent the state of documents at the
+   * given point in time.
+   */
+  stack: string[]
 }
 
 /**
@@ -24,9 +31,11 @@ export function useBundles(): BundlesState {
 
   return {
     data: bundlesAsArray,
+    bundles: state.bundles,
     deletedBundles,
     dispatch,
     error,
     loading: ['loading', 'initialising'].includes(state.state),
+    stack: state.releaseStack,
   }
 }