Add CommitInfoController with endpoint and unit tests

Introduced a new REST controller `CommitInfoController` to fetch the latest Git commit hash and date. Added corresponding unit tests in `CommitInfoControllerTest` and updated `HttpStatuses` with `INTERNAL_SERVER_ERROR` for response descriptions.

core/src/main/java/greencity/constant/HttpStatuses.java

@@ -12,4 +12,5 @@ public class HttpStatuses {
     public static final String NOT_FOUND = "Not Found";
     public static final String SEE_OTHER = "See Other";
     public static final String FOUND = "Found";
+    public static final String INTERNAL_SERVER_ERROR = "Internal Server Error";
 }

core/src/main/java/greencity/controller/CommitInfoController.java

@@ -0,0 +1,61 @@
+package greencity.controller;
+
+import greencity.constant.HttpStatuses;
+import greencity.dto.commitinfo.CommitInfoDto;
+import greencity.dto.commitinfo.CommitInfoErrorDto;
+import greencity.service.CommitInfoService;
+import io.swagger.v3.oas.annotations.Operation;
+import io.swagger.v3.oas.annotations.media.Content;
+import io.swagger.v3.oas.annotations.media.ExampleObject;
+import io.swagger.v3.oas.annotations.responses.ApiResponse;
+import lombok.RequiredArgsConstructor;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+/**
+ * Controller for fetching Git commit information.
+ */
+@RestController
+@RequestMapping("/commit-info")
+@RequiredArgsConstructor
+public class CommitInfoController {
+    private final CommitInfoService commitInfoService;
+
+    /**
+     * Endpoint to fetch the latest Git commit hash and date.
+     *
+     * @return {@link CommitInfoDto}, either success or error
+     */
+    @Operation(summary = "Get the latest commit hash and date.")
+    @ApiResponse(
+        responseCode = "200",
+        description = HttpStatuses.OK,
+        content = @Content(
+            mediaType = "application/json",
+            examples = @ExampleObject(
+                value = """
+                    {
+                        "commitHash": "d6e70c46b39857846f3f13ca9756c39448ab3d6f",
+                        "commitDate": "16/12/2024 10:55:00"
+                    }""")))
+    @ApiResponse(
+        responseCode = "500",
+        description = HttpStatuses.INTERNAL_SERVER_ERROR,
+        content = @Content(
+            mediaType = "application/json",
+            examples = @ExampleObject(
+                value = """
+                    {
+                        "error": "Failed to fetch commit info: Repository not found"
+                    }""")))
+    @GetMapping
+    public ResponseEntity<CommitInfoDto> getCommitInfo() {
+        CommitInfoDto commitInfo = commitInfoService.getLatestCommitInfo();
+        if (commitInfo instanceof CommitInfoErrorDto) {
+            return ResponseEntity.internalServerError().body(commitInfo);
+        }
+        return ResponseEntity.ok(commitInfo);
+    }
+}

core/src/test/java/greencity/controller/CommitInfoControllerTest.java

@@ -0,0 +1,66 @@
+package greencity.controller;
+
+import greencity.dto.commitinfo.CommitInfoDto;
+import greencity.dto.commitinfo.CommitInfoErrorDto;
+import greencity.dto.commitinfo.CommitInfoSuccessDto;
+import greencity.service.CommitInfoService;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+import static org.mockito.Mockito.*;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.springframework.http.MediaType;
+import org.springframework.test.web.servlet.MockMvc;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+import org.springframework.test.web.servlet.setup.MockMvcBuilders;
+
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+
+@ExtendWith(MockitoExtension.class)
+class CommitInfoControllerTest {
+    @InjectMocks
+    private CommitInfoController commitInfoController;
+
+    @Mock
+    private CommitInfoService commitInfoService;
+
+    private MockMvc mockMvc;
+
+    @BeforeEach
+    void setUp() {
+        mockMvc = MockMvcBuilders.standaloneSetup(commitInfoController).build();
+    }
+
+    private static final String COMMIT_INFO_URL = "/commit-info";
+    private static final String COMMIT_HASH = "abc123";
+    private static final String COMMIT_DATE = "16/12/2024 12:06:32";
+    private static final String ERROR_MESSAGE = "Failed to fetch commit info due to I/O error: Missing object";
+
+    @Test
+    void getCommitInfoReturnsSuccessTest() throws Exception {
+        CommitInfoDto commitInfoDto = new CommitInfoSuccessDto(COMMIT_HASH, COMMIT_DATE);
+        when(commitInfoService.getLatestCommitInfo()).thenReturn(commitInfoDto);
+
+        mockMvc.perform(get(COMMIT_INFO_URL).accept(MediaType.APPLICATION_JSON))
+            .andExpect(status().isOk())
+            .andExpect(jsonPath("$.commitHash").value(COMMIT_HASH))
+            .andExpect(jsonPath("$.commitDate").value(COMMIT_DATE));
+
+        verify(commitInfoService, times(1)).getLatestCommitInfo();
+    }
+
+    @Test
+    void getCommitInfoReturnsErrorTest() throws Exception {
+        CommitInfoDto commitInfoDto = new CommitInfoErrorDto(ERROR_MESSAGE);
+        when(commitInfoService.getLatestCommitInfo()).thenReturn(commitInfoDto);
+
+        mockMvc.perform(get(COMMIT_INFO_URL).accept(MediaType.APPLICATION_JSON))
+            .andExpect(status().isInternalServerError())
+            .andExpect(jsonPath("$.error").value(ERROR_MESSAGE));
+
+        verify(commitInfoService, times(1)).getLatestCommitInfo();
+    }
+}