feat(csm): support perspective modes when optimistically applying doc…

…ument mutations

package.json

@@ -139,6 +139,7 @@
     "@rollup/plugin-commonjs": "^25.0.7",
     "@rollup/plugin-node-resolve": "^15.2.3",
     "@sanity/pkg-utils": "^3.3.7",
+    "@types/json-diff": "^1.0.3",
     "@types/node": "^20.8.8",
     "@typescript-eslint/eslint-plugin": "^6.18.0",
     "@typescript-eslint/parser": "^6.18.0",
@@ -149,6 +150,7 @@
     "eslint-plugin-simple-import-sort": "^10.0.0",
     "faucet": "^0.0.4",
     "happy-dom": "^12.10.3",
+    "json-diff": "^1.0.6",
     "ls-engines": "^0.9.1",
     "nock": "^13.4.0",
     "prettier": "^3.1.1",

src/csm/applySourceDocuments.ts

@@ -1,9 +1,11 @@
+import {DRAFTS_PREFIX, getPublishedId} from './getPublishedId'
 import {parseJsonPath} from './jsonPath'
 import {resolveMapping} from './resolveMapping'
 import * as paths from './studioPath'
 import type {
   Any,
   ApplySourceDocumentsUpdateFunction,
+  ClientPerspective,
   ContentSourceMap,
   ContentSourceMapDocuments,
   Path,
@@ -25,9 +27,14 @@ export function applySourceDocuments<Result = unknown>(
     sourceDocument: ContentSourceMapDocuments[number],
   ) => SanityDocument | undefined,
   updateFn: ApplySourceDocumentsUpdateFunction = defaultUpdateFunction,
+  perspective: ClientPerspective = 'raw',
 ): Result {
   if (!resultSourceMap) return result
 
+  if (perspective !== 'published' && perspective !== 'raw' && perspective !== 'previewDrafts') {
+    throw new Error(`Unknown perspective "${perspective}"`)
+  }
+
   return walkMap(JSON.parse(JSON.stringify(result)), (value, path) => {
     const resolveMappingResult = resolveMapping(path, resultSourceMap)
     if (!resolveMappingResult) {
@@ -48,14 +55,45 @@ export function applySourceDocuments<Result = unknown>(
     const sourcePath = resultSourceMap.paths[mapping.source.path]
 
     if (sourceDocument) {
-      const cachedDocument = getCachedDocument(sourceDocument)
+      const parsedPath = parseJsonPath(sourcePath + pathSuffix)
+      const stringifiedPath = paths.toString(parsedPath as Path)
+
+      // The _id is sometimes used used as `key` in lists, and should not be changed optimistically
+      if (stringifiedPath === '_id') {
+        return value
+      }
+
+      let cachedDocument: SanityDocument | undefined
+      if (perspective === 'previewDrafts') {
+        cachedDocument = getCachedDocument(
+          sourceDocument._id.startsWith(DRAFTS_PREFIX)
+            ? sourceDocument
+            : {...sourceDocument, _id: `${DRAFTS_PREFIX}.${sourceDocument._id}}`},
+        )
+        if (!cachedDocument) {
+          cachedDocument = getCachedDocument(
+            sourceDocument._id.startsWith(DRAFTS_PREFIX)
+              ? {...sourceDocument, _id: getPublishedId(sourceDocument._id)}
+              : sourceDocument,
+          )
+        }
+        if (cachedDocument) {
+          cachedDocument = {
+            ...cachedDocument,
+            _id: getPublishedId(sourceDocument._id),
+            _originalId: sourceDocument._id,
+          }
+        }
+      } else {
+        cachedDocument = getCachedDocument(sourceDocument)
+      }
+
       if (!cachedDocument) {
         return value
       }
 
-      const parsedPath = parseJsonPath(sourcePath + pathSuffix)
       const changedValue = cachedDocument
-        ? paths.get<Result[keyof Result]>(cachedDocument, paths.toString(parsedPath as Path), value)
+        ? paths.get<Result[keyof Result]>(cachedDocument, stringifiedPath, value)
         : value
       return value === changedValue
         ? value

src/csm/getPublishedId.ts

@@ -1,4 +1,4 @@
-const DRAFTS_PREFIX = 'drafts.'
+export const DRAFTS_PREFIX = 'drafts.'
 
 /** @internal */
 export function getPublishedId(id: string): string {

src/csm/types.ts

@@ -3,6 +3,7 @@ import {Path} from './studioPath'
 
 export type {
   Any,
+  ClientPerspective,
   ContentSourceMap,
   ContentSourceMapDocument,
   ContentSourceMapDocumentBase,