[COT-14]Feature: 기수 단건 조회

src/main/java/org/cotato/csquiz/api/generation/controller/GenerationController.java

@@ -1,5 +1,6 @@
 package org.cotato.csquiz.api.generation.controller;
 
+import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.tags.Tag;
 import jakarta.validation.Valid;
 import java.time.LocalDate;
@@ -16,6 +17,7 @@
 import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.PatchMapping;
+import org.springframework.web.bind.annotation.PathVariable;
 import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RequestMapping;
@@ -52,9 +54,17 @@ public ResponseEntity<Void> changeGenerationPeriod(@RequestBody @Valid ChangeGen
         return ResponseEntity.noContent().build();
     }
 
+    @Operation(summary = "현재 날짜 기준 세션 정보 반환 API")
     @GetMapping("/current")
     public ResponseEntity<GenerationInfoResponse> findCurrentGeneration() {
         LocalDate currentDate = LocalDate.now();
         return ResponseEntity.ok().body(generationService.findCurrentGeneration(currentDate));
     }
+
+    @Operation(summary = "기수 단건 조회 API")
+    @GetMapping("/{generationId}")
+    public ResponseEntity<GenerationInfoResponse> findGenerationById(
+            @PathVariable("generationId") Long generationId) {
+        return ResponseEntity.ok().body(generationService.findGenerationById(generationId));
+    }
 }

src/main/java/org/cotato/csquiz/api/generation/dto/GenerationInfoResponse.java

@@ -1,18 +1,23 @@
 package org.cotato.csquiz.api.generation.dto;
 
+import java.time.LocalDate;
 import org.cotato.csquiz.domain.generation.entity.Generation;
 
 public record GenerationInfoResponse(
         Long generationId,
         Integer generationNumber,
-        Integer sessionCount
+        Integer sessionCount,
+        LocalDate startDate,
+        LocalDate endDate
 ) {
 
     public static GenerationInfoResponse from(Generation generation) {
         return new GenerationInfoResponse(
                 generation.getId(),
                 generation.getNumber(),
-                generation.getSessionCount()
+                generation.getSessionCount(),
+                generation.getPeriod().getStartDate(),
+                generation.getPeriod().getEndDate()
         );
     }
 }

src/main/java/org/cotato/csquiz/domain/generation/service/GenerationService.java

@@ -83,4 +83,10 @@ public GenerationInfoResponse findCurrentGeneration(LocalDate currentDate) {
                         .orElseThrow(() -> new EntityNotFoundException("현재 날짜에 해당하는 기수가 존재하지 않습니다")));
         return GenerationInfoResponse.from(currentGeneration);
     }
+
+    public GenerationInfoResponse findGenerationById(Long generationId) {
+        Generation generation = generationRepository.findById(generationId)
+                .orElseThrow(() -> new EntityNotFoundException("찾으려는 기수가 존재하지 않습니다."));
+        return GenerationInfoResponse.from(generation);
+    }
 }