From f8f1899468557b9859c2f50edccee8beb63c2fc3 Mon Sep 17 00:00:00 2001
From: Fifolu Akinyemi <fkinyemi@gmail.com>
Date: Sat, 26 Oct 2024 14:26:44 +0100
Subject: [PATCH] Caching for find multiple holiday invites endpoint

---
 .idea/workspace.xml                           |  5 ++-
 .../HolidayInviteController.java              |  2 +-
 .../holidayInvite/HolidayInviteService.java   | 32 ++++++++++++++++---
 3 files changed, 31 insertions(+), 8 deletions(-)

diff --git a/.idea/workspace.xml b/.idea/workspace.xml
index 5e4c769..a740850 100644
--- a/.idea/workspace.xml
+++ b/.idea/workspace.xml
@@ -5,9 +5,8 @@
   </component>
   <component name="ChangeListManager">
     <list default="true" id="9dd73e5b-8b9d-4958-9830-cf76380772ff" name="Changes" comment="Extend create holiday endpoints to find and update entities in cache.">
-      <change beforePath="$PROJECT_DIR$/.idea/workspace.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/workspace.xml" afterDir="false" />
-      <change beforePath="$PROJECT_DIR$/src/main/java/com/example/holidayplanner/groupInvite/GroupInviteController.java" beforeDir="false" afterPath="$PROJECT_DIR$/src/main/java/com/example/holidayplanner/groupInvite/GroupInviteController.java" afterDir="false" />
-      <change beforePath="$PROJECT_DIR$/src/main/java/com/example/holidayplanner/groupInvite/GroupInviteService.java" beforeDir="false" afterPath="$PROJECT_DIR$/src/main/java/com/example/holidayplanner/groupInvite/GroupInviteService.java" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/src/main/java/com/example/holidayplanner/holidayInvite/HolidayInviteController.java" beforeDir="false" afterPath="$PROJECT_DIR$/src/main/java/com/example/holidayplanner/holidayInvite/HolidayInviteController.java" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/src/main/java/com/example/holidayplanner/holidayInvite/HolidayInviteService.java" beforeDir="false" afterPath="$PROJECT_DIR$/src/main/java/com/example/holidayplanner/holidayInvite/HolidayInviteService.java" afterDir="false" />
     </list>
     <option name="SHOW_DIALOG" value="false" />
     <option name="HIGHLIGHT_CONFLICTS" value="true" />
diff --git a/src/main/java/com/example/holidayplanner/holidayInvite/HolidayInviteController.java b/src/main/java/com/example/holidayplanner/holidayInvite/HolidayInviteController.java
index f0ec026..1ae6b72 100644
--- a/src/main/java/com/example/holidayplanner/holidayInvite/HolidayInviteController.java
+++ b/src/main/java/com/example/holidayplanner/holidayInvite/HolidayInviteController.java
@@ -28,7 +28,7 @@ public HolidayInviteController(HolidayInviteService holidayInviteService) {
 
     @PostMapping("/findmultiplebyid")
     @Operation(summary = "Find multiple holiday invites by their ids")
-    public ResponseEntity findMultipleById(@RequestBody List<String> holidayInviteIds) throws JsonProcessingException {
+    public ResponseEntity<String> findMultipleById(@RequestBody List<String> holidayInviteIds) throws JsonProcessingException {
         return holidayInviteService.findMultipleById(holidayInviteIds);
     }
 }
diff --git a/src/main/java/com/example/holidayplanner/holidayInvite/HolidayInviteService.java b/src/main/java/com/example/holidayplanner/holidayInvite/HolidayInviteService.java
index 80fb879..7b764ab 100644
--- a/src/main/java/com/example/holidayplanner/holidayInvite/HolidayInviteService.java
+++ b/src/main/java/com/example/holidayplanner/holidayInvite/HolidayInviteService.java
@@ -1,11 +1,14 @@
 package com.example.holidayplanner.holidayInvite;
 
+import com.example.holidayplanner.helpers.CacheHelper;
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.cache.CacheManager;
 import org.springframework.http.ResponseEntity;
 import org.springframework.stereotype.Service;
 
+import java.util.ArrayList;
 import java.util.List;
 
 @Service
@@ -14,22 +17,25 @@ public class HolidayInviteService {
     @Autowired
     private final HolidayInviteRepository holidayInviteRepository;
 
+    private final CacheHelper<HolidayInvite> holidayInviteCacheHelper;
+
     @Autowired
     private final ObjectMapper objectMapper;
 
-    public HolidayInviteService(HolidayInviteRepository holidayInviteRepository, ObjectMapper objectMapper) {
+    public HolidayInviteService(HolidayInviteRepository holidayInviteRepository, ObjectMapper objectMapper, CacheManager cacheManager) {
         this.holidayInviteRepository = holidayInviteRepository;
         this.objectMapper = objectMapper;
+        holidayInviteCacheHelper = new CacheHelper<>(cacheManager, "holiday invites", HolidayInvite.class);
     }
 
-    public ResponseEntity findMultipleById(List<String> holidayInviteIds) throws JsonProcessingException {
+    public ResponseEntity<String> findMultipleById(List<String> holidayInviteIds) throws JsonProcessingException {
         if (holidayInviteIds == null || holidayInviteIds.isEmpty()) {
             return ResponseEntity.badRequest().body("No holiday invite ids provided");
         }
 
-        Iterable<HolidayInvite> holidayInvite = holidayInviteRepository.findAllById(holidayInviteIds);
+        List<HolidayInvite> holidayInvite = findMultipleGroupInvitesByIdInCacheOrDatabase(holidayInviteIds);
 
-        if (holidayInvite == null) {
+        if (holidayInvite.isEmpty()) {
             return ResponseEntity.badRequest().body("No holiday invites found");
         }
 
@@ -37,4 +43,22 @@ public ResponseEntity findMultipleById(List<String> holidayInviteIds) throws Jso
 
         return ResponseEntity.ok().body(holidayInviteJson);
     }
+
+    public List<HolidayInvite> findMultipleGroupInvitesByIdInCacheOrDatabase(List<String> holidayInviteIds) {
+        List<HolidayInvite> cachedHolidayInvites = holidayInviteCacheHelper.getCachedEntries(holidayInviteIds);
+
+        List<String> idsToFetch = holidayInviteIds.stream().filter(id -> cachedHolidayInvites.stream().noneMatch(holidayInvite -> holidayInvite.getId().equals(id))).toList();
+
+        if (idsToFetch.isEmpty()) {
+            return cachedHolidayInvites;
+        }
+
+        List<HolidayInvite> freshHolidayInvites = holidayInviteRepository.findAllById(idsToFetch);
+
+        holidayInviteCacheHelper.cacheEntries(freshHolidayInvites, HolidayInvite::getId);
+        List<HolidayInvite> allHolidayInvites = new ArrayList<>(cachedHolidayInvites);
+        allHolidayInvites.addAll(freshHolidayInvites);
+
+        return allHolidayInvites;
+    }
 }