added logic to fetch a page's relations

Author: rimonhanna

examples/minimal/pages/[pageId].tsx

@@ -6,7 +6,7 @@ import notion from '../lib/notion'
 
 export const getStaticProps = async (context: any) => {
   const pageId = (context.params.pageId as string) || rootNotionPageId
-  const recordMap = await notion.getPage(pageId)
+  const recordMap = await notion.getPage(pageId, { fetchRelationPages: true })
 
   return {
     props: {

packages/notion-client/src/notion-api.ts

@@ -53,6 +53,7 @@ export class NotionAPI {
       chunkNumber = 0,
       throwOnCollectionErrors = false,
       collectionReducerLimit = 999,
+      fetchRelationPages = true, // New option
       kyOptions
     }: {
       concurrency?: number
@@ -63,6 +64,7 @@ export class NotionAPI {
       chunkNumber?: number
       throwOnCollectionErrors?: boolean
       collectionReducerLimit?: number
+      fetchRelationPages?: boolean // New option
       kyOptions?: KyOptions
     } = {}
   ): Promise<notion.ExtendedRecordMap> {
@@ -220,6 +222,73 @@ export class NotionAPI {
       await this.addSignedUrls({ recordMap, contentBlockIds, kyOptions })
     }
 
+    if (fetchRelationPages) {
+      const maxIterations = 10 // Limit iterations to prevent infinite loops
+      for (let i = 0; i < maxIterations; ++i) {
+        const allRelationPageIdsInThisIteration = new Set<string>()
+
+        for (const blockId of Object.keys(recordMap.block)) {
+          const blockValue = recordMap.block[blockId]?.value
+          if (
+            blockValue?.parent_table === 'collection' &&
+            blockValue?.parent_id
+          ) {
+            const collection = recordMap.collection[blockValue.parent_id]?.value
+            if (collection?.schema) {
+              for (const propertyId of Object.keys(
+                blockValue.properties || {}
+              )) {
+                const schema = collection.schema[propertyId]
+                if (schema?.type === 'relation') {
+                  const decorations = blockValue.properties![propertyId]
+                  if (decorations && Array.isArray(decorations)) {
+                    for (const decoration of decorations) {
+                      if (
+                        Array.isArray(decoration) &&
+                        decoration.length > 1 &&
+                        decoration[0] === '‣'
+                      ) {
+                        const pagePointer = decoration[1]?.[0]
+                        if (
+                          Array.isArray(pagePointer) &&
+                          pagePointer.length > 1 &&
+                          pagePointer[0] === 'p'
+                        ) {
+                          allRelationPageIdsInThisIteration.add(pagePointer[1])
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+
+        const pendingRelationPageIds = Array.from(
+          allRelationPageIdsInThisIteration
+        ).filter((id) => !recordMap.block[id]?.value)
+
+        if (!pendingRelationPageIds.length) {
+          break // No new related pages to fetch
+        }
+
+        try {
+          const newBlocks = await this.getBlocks(
+            pendingRelationPageIds,
+            kyOptions
+          ).then((res) => res.recordMap.block)
+          recordMap.block = { ...recordMap.block, ...newBlocks }
+        } catch (err: any) {
+          console.warn(
+            'NotionAPI getBlocks error during fetchRelationPages:',
+            err.message
+          )
+          //TODO: Decide if we should break or continue if some blocks fail
+        }
+      }
+    }
+
     return recordMap
   }