feat : add swagger-ui & fix auto eviction for /potd endpoint

Author: Rajat069

pom.xml

@@ -121,6 +121,13 @@
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-aop</artifactId>
         </dependency>
+
+        <dependency>
+            <groupId>org.springdoc</groupId>
+            <artifactId>springdoc-openapi-starter-webmvc-ui</artifactId>
+            <version>2.8.13</version>
+        </dependency>
+
     </dependencies>
 
 	<build>

src/main/java/com/rajat_singh/leetcode_api/controller/LeetCodeQuestionsController.java

@@ -8,6 +8,7 @@
 import com.rajat_singh.leetcode_api.repository.QuestionsRepository;
 import com.rajat_singh.leetcode_api.service.LeetCodeQuestionsService;
 import lombok.RequiredArgsConstructor;
+import org.springdoc.core.annotations.ParameterObject;
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.Pageable;
 import org.springframework.http.ResponseEntity;
@@ -33,7 +34,7 @@ public class LeetCodeQuestionsController {
      * e.g., /api/v1/questions?page=0&size=20
      */
     @GetMapping()
-    public ResponseEntity<Page<QuestionResponseDTO>> getAllQuestions(Pageable pageable){
+    public ResponseEntity<Page<QuestionResponseDTO>> getAllQuestions(@ParameterObject Pageable pageable){
         Logger.info("Fetching questions from database with pagination: {}", pageable);
 
         Page<QuestionEntity> entityPage = questionsRepository.findAll(pageable);
@@ -54,6 +55,9 @@ public ResponseEntity<Page<QuestionResponseDTO>> getAllQuestions(Pageable pageab
         return ResponseEntity.ok(dtoPage);
     }
 
+    /**
+    * Retrieves the current Problem of the Day (POTD) from the database
+    */
     @GetMapping("/potd")
     public ResponseEntity<QuestionResponseDTO> getPotd() {
         Logger.info("Fetching POTD from database");
@@ -66,5 +70,4 @@ public ResponseEntity<QuestionResponseDTO> getPotd() {
         return ResponseEntity.ok(dto);
     }
 
-
 }

src/main/java/com/rajat_singh/leetcode_api/repository/QuestionsRepository.java

@@ -1,6 +1,7 @@
 package com.rajat_singh.leetcode_api.repository;
 
 import com.rajat_singh.leetcode_api.entity.QuestionEntity;
+import jakarta.transaction.Transactional;
 import org.springframework.data.jpa.repository.JpaRepository;
 import org.springframework.data.jpa.repository.JpaSpecificationExecutor;
 import org.springframework.stereotype.Repository;
@@ -12,4 +13,6 @@ public interface QuestionsRepository extends JpaRepository<QuestionEntity,Intege
     QuestionEntity findByTitleSlug(String title);
     QuestionEntity findByIsProblemOfTheDayTrue();
 
+    @Transactional
+    void deleteByIsProblemOfTheDayTrue();
 }

src/main/java/com/rajat_singh/leetcode_api/scheduler/LeetCodeSyncScheduler.java

@@ -7,6 +7,7 @@
 import com.rajat_singh.leetcode_api.entity.TopicTag;
 import com.rajat_singh.leetcode_api.mappers.QuestionMapper;
 import com.rajat_singh.leetcode_api.repository.QuestionsRepository;
+import com.rajat_singh.leetcode_api.utility.DBUtilities;
 import jakarta.annotation.PostConstruct;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.scheduling.annotation.Async;
@@ -33,6 +34,9 @@ public class LeetCodeSyncScheduler {
     @Autowired
     private  QuestionMapper questionMapper;
 
+    @Autowired
+    private DBUtilities dbUtilities;
+
     // Runs every week for full data sync
     @Async
     @Scheduled(fixedRate = WEEK_IN_MILLISECONDS)
@@ -108,6 +112,20 @@ public void syncPOTD() {
         Logger.info("LeetCode [POTD] sync completed in {} seconds.", (endTime - startTime) / 1000);
     }
 
+    @Scheduled(cron = "0 30 5 * * ?", zone = "Asia/Kolkata") // Runs every day at 5:30 AM (IST) for POTD removal)
+    @Async
+    public void removePOTD() {
+        Logger.info("Starting LeetCode [POTD] removal... at {}", DateFormat.getDateInstance().format(System.currentTimeMillis()));
+        Long startTime = System.currentTimeMillis();
+        QuestionEntity existingQuestion = questionRepository.findByIsProblemOfTheDayTrue();
+        if(Objects.nonNull(existingQuestion)){
+            existingQuestion.setIsProblemOfTheDay(false);
+            questionRepository.save(existingQuestion);
+        }
+        Long endTime = System.currentTimeMillis();
+        Logger.info("LeetCode [POTD] removal completed in {} seconds.", (endTime - startTime) / 1000);
+    }
+
     @PostConstruct
     public void initialSync() {
         syncPOTD();

src/main/java/com/rajat_singh/leetcode_api/utility/DBUtilities.java

@@ -0,0 +1,19 @@
+package com.rajat_singh.leetcode_api.utility;
+
+import com.rajat_singh.leetcode_api.repository.QuestionsRepository;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Component;
+import org.tinylog.Logger;
+
+@Component
+public class DBUtilities {
+
+    @Autowired
+    private QuestionsRepository questionsRepository;
+
+    public void manualPOTDEviction(){
+        Logger.info("Deleting POTD from database");
+        questionsRepository.deleteByIsProblemOfTheDayTrue();
+    }
+
+}

src/main/resources/application.yml

@@ -67,3 +67,13 @@ resilience4j:
         limitRefreshPeriod: 1s            # ...per 1 second.
         timeoutDuration: 2s               # How long to wait for permission
         register-health-indicator: true
+
+springdoc:
+  api-docs:
+    path: /v3/api-docs
+  swagger-ui:
+    path: /swagger-ui/index.html
+  info:
+    title: leetstats-api
+    description: "The API for retrieving your LeetCode profile & Problems statistics"
+    version: "0.0.1-SNAPSHOT"