temporarily stop database connection while backing up database files (#1867)

* fix backup

* limit the scope of modification to Windows system and h2 database

* Code style union

* Code style union

src/main/java/run/halo/app/service/impl/BackupServiceImpl.java

@@ -8,7 +8,10 @@ import static run.halo.app.utils.FileUtils.checkDirectoryTraversal;
 
 import com.fasterxml.jackson.core.type.TypeReference;
 import com.fasterxml.jackson.databind.ObjectMapper;
+import com.zaxxer.hikari.HikariDataSource;
+import com.zaxxer.hikari.pool.HikariPool;
 import java.io.IOException;
+import java.lang.reflect.Field;
 import java.net.MalformedURLException;
 import java.nio.file.Files;
 import java.nio.file.NoSuchFileException;
@@ -28,6 +31,10 @@ import java.util.stream.Stream;
 import java.util.zip.ZipOutputStream;
 import lombok.extern.slf4j.Slf4j;
 import org.apache.commons.lang3.StringUtils;
+import org.apache.commons.lang3.SystemUtils;
+import org.apache.logging.log4j.core.util.ReflectionUtil;
+import org.springframework.beans.factory.NoSuchBeanDefinitionException;
+import org.springframework.context.ApplicationContext;
 import org.springframework.context.ApplicationEventPublisher;
 import org.springframework.core.io.Resource;
 import org.springframework.core.io.UrlResource;
@@ -177,6 +184,8 @@ public class BackupServiceImpl implements BackupService {
 
     private final ApplicationEventPublisher eventPublisher;
 
+    private final ApplicationContext appContext;
+
     public BackupServiceImpl(AttachmentService attachmentService, CategoryService categoryService,
         CommentBlackListService commentBlackListService, JournalService journalService,
         JournalCommentService journalCommentService, LinkService linkService, LogService logService,
@@ -189,7 +198,7 @@ public class BackupServiceImpl implements BackupService {
         SheetCommentService sheetCommentService, SheetMetaService sheetMetaService,
         TagService tagService, ThemeSettingService themeSettingService, UserService userService,
         OneTimeTokenService oneTimeTokenService, HaloProperties haloProperties,
-        ApplicationEventPublisher eventPublisher) {
+        ApplicationEventPublisher eventPublisher, ApplicationContext appContext) {
         this.attachmentService = attachmentService;
         this.categoryService = categoryService;
         this.commentBlackListService = commentBlackListService;
@@ -216,6 +225,7 @@ public class BackupServiceImpl implements BackupService {
         this.oneTimeTokenService = oneTimeTokenService;
         this.haloProperties = haloProperties;
         this.eventPublisher = eventPublisher;
+        this.appContext = appContext;
     }
 
     @Override
@@ -246,6 +256,26 @@ public class BackupServiceImpl implements BackupService {
             }
             Path haloZipPath = Files.createFile(haloZipFilePath);
 
+            boolean dbClosed = false;
+            if (options.contains("db") && SystemUtils.IS_OS_WINDOWS) {
+                try {
+                    HikariDataSource dataSource = appContext.getBean(HikariDataSource.class);
+                    if (dataSource.getDriverClassName().equals("org.h2.Driver")) {
+                        try {
+                            Field poolField = HikariDataSource.class.getDeclaredField(
+                                "pool");
+                            HikariPool pool =
+                                (HikariPool) ReflectionUtil.getFieldValue(poolField, dataSource);
+                            pool.shutdown();
+                            dbClosed = true;
+                        } catch (InterruptedException | NoSuchFieldException e) {
+                            throw new ServiceException("Failed to close H2 database", e);
+                        }
+                    }
+                } catch (NoSuchBeanDefinitionException e) {
+                    throw new ServiceException("Bean HikariDataSource doesn't exists");
+                }
+            }
             // Zip halo
             run.halo.app.utils.FileUtils
                 .zip(Paths.get(this.haloProperties.getWorkDir()), haloZipPath,
@@ -260,6 +290,16 @@ public class BackupServiceImpl implements BackupService {
                         return false;
                     });
 
+            if (dbClosed) {
+                try {
+                    Field poolField = HikariDataSource.class.getDeclaredField(
+                        "pool");
+                    HikariDataSource dataSource = appContext.getBean(HikariDataSource.class);
+                    ReflectionUtil.setFieldValue(poolField, dataSource, new HikariPool(dataSource));
+                } catch (NoSuchFieldException e) {
+                    throw new ServiceException("Failed to reopen H2 database", e);
+                }
+            }
             // Build backup dto
             return buildBackupDto(BACKUP_RESOURCE_BASE_URI, haloZipPath);
         } catch (IOException e) {