feat: Merge search payload with pagintion link body

Author: oliverroick

src/hooks/useStacSearch.test.ts

@@ -259,4 +259,42 @@ describe('useStacSearch', () => {
     expect(result.current.results).toEqual({ data: '12345' });
     expect(postPayload).toEqual(response.links[0].body);
   });
+
+  it('merges pagination body', async () => {
+    const response = {
+      links: [{
+        rel: 'previous',
+        type: 'application/geo+json',
+        method: 'POST',
+        href: 'https://example.com/stac/search',
+        body: {
+          limit: 25,
+          token: 'prev:abc123',
+          merge: true
+        }
+      }]
+    };
+    fetch.mockResponseOnce(JSON.stringify(response));
+
+    const { result, waitForNextUpdate } = renderHook(
+      () => useStacSearch(stacApi)
+    );
+
+    act(() => result.current.setBbox([-0.59, 51.24, 0.30, 51.74]));
+    act(() => result.current.submit());
+    await waitForNextUpdate(); // wait to set results
+    expect(result.current.results).toEqual(response);
+    expect(result.current.previousPage).toBeDefined();
+
+    fetch.mockResponseOnce(JSON.stringify({ data: '12345' }));
+    act(() => result.current.previousPage && result.current.previousPage());
+    await waitForNextUpdate();
+
+    const postPayload = parseRequestPayload(fetch.mock.calls[1][1]);
+    expect(result.current.results).toEqual({ data: '12345' });
+    expect(postPayload).toEqual({
+      bbox: [-0.59, 51.24, 0.30, 51.74],
+      ...response.links[0].body
+    });
+  });
 });

src/hooks/useStacSearch.ts

@@ -1,7 +1,15 @@
 import { useCallback, useState } from 'react';
 import StacApi from '../stac-api';
 
-import type { Link, Item, Bbox, CollectionIdList, ApiError, SearchPayload } from '../types';
+import type {
+  Link,
+  Item,
+  Bbox,
+  CollectionIdList,
+  ApiError,
+  SearchPayload,
+  LinkBody
+} from '../types';
 
 type SearchResponse = {
   type: 'FeatureCollection'
@@ -49,6 +57,15 @@ function useStacSearch(stacApi: StacApi): StacSearchHook {
     }, []
   );
 
+  const getSearchPayload = useCallback(
+    () => ({
+      bbox,
+      collections,
+      dateRange: { from: dateRangeFrom, to: dateRangeTo }
+    }),
+    [ bbox, collections, dateRangeFrom, dateRangeTo ]
+  );
+
   const executeSearch = useCallback(
     (payload: SearchPayload) => {
       setResults(undefined);
@@ -72,11 +89,17 @@ function useStacSearch(stacApi: StacApi): StacSearchHook {
   const flipPage = useCallback(
     (link?: Link) => {
       if (link) {
-        const payload = link.body as SearchPayload;
+        let payload = link.body as LinkBody;
+        if (payload.merge) {
+          payload = {
+            ...payload,
+            ...getSearchPayload()
+          };
+        }
         executeSearch(payload);
       }
     },
-    [executeSearch]
+    [executeSearch, getSearchPayload]
   );
 
   const nextPageFn = useCallback(
@@ -91,13 +114,9 @@ function useStacSearch(stacApi: StacApi): StacSearchHook {
 
   const submit = useCallback(
     () => {
-      const payload = {
-        bbox,
-        collections,
-        dateRange: { from: dateRangeFrom, to: dateRangeTo }
-      };
+      const payload = getSearchPayload();
       executeSearch(payload); 
-    }, [executeSearch, bbox, collections, dateRangeFrom, dateRangeTo]
+    }, [executeSearch, getSearchPayload]
   );
 
   return {

src/types.ts

@@ -11,6 +11,16 @@ export type DateRange = {
   to?: string
 }
 
+export type SearchPayload = {
+  bbox?: Bbox,
+  collections?: CollectionIdList,
+  dateRange?: DateRange,
+}
+
+export type LinkBody = SearchPayload & {
+  merge?: boolean
+}
+
 export type Link = {
   href: string
   rel: string
@@ -20,7 +30,7 @@ export type Link = {
   length?: number
   method?: string
   headers?: GenericObject
-  body?: SearchPayload
+  body?: LinkBody
   merge?: boolean
 }
 
@@ -47,9 +57,3 @@ export type ApiError = {
   status: number,
   statusText: string
 }
-
-export type SearchPayload = {
-  bbox?: Bbox,
-  collections?: CollectionIdList,
-  dateRange?: DateRange
-}