Add activity log (#16)

server/src/main/java/io/flexwork/config/AsyncConfiguration.java

@@ -9,10 +9,12 @@
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.Profile;
+import org.springframework.core.task.TaskExecutor;
 import org.springframework.scheduling.annotation.AsyncConfigurer;
 import org.springframework.scheduling.annotation.EnableAsync;
 import org.springframework.scheduling.annotation.EnableScheduling;
 import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;
+import org.springframework.security.task.DelegatingSecurityContextTaskExecutor;
 import tech.jhipster.async.ExceptionHandlingAsyncTaskExecutor;
 
 @Configuration
@@ -41,6 +43,19 @@ public Executor getAsyncExecutor() {
         return new ExceptionHandlingAsyncTaskExecutor(executor);
     }
 
+    @Bean(name = "auditLogExecutor")
+    public TaskExecutor auditLogaskExecutor() {
+        ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
+        executor.setCorePoolSize(10);
+        executor.setMaxPoolSize(50);
+        executor.setQueueCapacity(100);
+        executor.setThreadNamePrefix("SecurityContextAsync-");
+        executor.initialize();
+
+        // Wrap the executor with DelegatingSecurityContextTaskExecutor
+        return new DelegatingSecurityContextTaskExecutor(executor);
+    }
+
     @Override
     public AsyncUncaughtExceptionHandler getAsyncUncaughtExceptionHandler() {
         return new SimpleAsyncUncaughtExceptionHandler();

server/src/main/java/io/flexwork/modules/audit/AbstractEntityFieldHandlerRegistry.java

@@ -0,0 +1,59 @@
+package io.flexwork.modules.audit;
+
+import io.flexwork.modules.collab.domain.EntityType;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.function.BiFunction;
+
+public abstract class AbstractEntityFieldHandlerRegistry implements EntityFieldHandlerRegistry {
+
+    private final Map<String, BiFunction<Object, Object, String>> fieldHandlers = new HashMap<>();
+
+    /**
+     * Add a field handler for a specific field.
+     *
+     * @param fieldName The name of the field.
+     * @param handler A function that processes the old and new values of the field.
+     */
+    protected void addFieldHandler(String fieldName, BiFunction<Object, Object, String> handler) {
+        fieldHandlers.put(fieldName, handler);
+    }
+
+    /**
+     * Get the handler for a specific field.
+     *
+     * @param fieldName The name of the field.
+     * @return A handler function that processes the old and new values of the field.
+     */
+    @Override
+    public BiFunction<Object, Object, String> getHandler(String fieldName) {
+        return fieldHandlers.get(fieldName);
+    }
+
+    /**
+     * Initialize field handlers for this entity. Subclasses must define their field-specific logic
+     * in this method.
+     */
+    protected abstract void initializeFieldHandlers();
+
+    /** Constructor to ensure field handlers are initialized in subclasses. */
+    public AbstractEntityFieldHandlerRegistry() {
+        initializeFieldHandlers();
+    }
+
+    /**
+     * Subclasses must provide the entity's class.
+     *
+     * @return The class of the entity this registry handles.
+     */
+    @Override
+    public abstract Class<?> getEntityClass();
+
+    /**
+     * Subclasses must provide the entity's EntityType.
+     *
+     * @return The EntityType of the entity.
+     */
+    @Override
+    public abstract EntityType getEntityType();
+}

server/src/main/java/io/flexwork/modules/audit/ActivityLogUtils.java

@@ -0,0 +1,33 @@
+package io.flexwork.modules.audit;
+
+import static j2html.TagCreator.*;
+
+import j2html.tags.DomContent;
+import java.util.List;
+
+public class ActivityLogUtils {
+
+    public static String generateHtmlLog(List<AuditUtils.FieldChange> changes) {
+        DomContent htmlContent =
+                table().with(
+                                thead(tr(th("Field"), th("Old Value"), th("New Value"))),
+                                tbody(
+                                        each(
+                                                changes,
+                                                change ->
+                                                        tr(
+                                                                td(change.getFieldName()),
+                                                                td(
+                                                                        change.getOldValue() != null
+                                                                                ? change.getOldValue()
+                                                                                        .toString()
+                                                                                : "N/A"),
+                                                                td(
+                                                                        change.getNewValue() != null
+                                                                                ? change.getNewValue()
+                                                                                        .toString()
+                                                                                : "N/A")))));
+
+        return htmlContent.render();
+    }
+}

server/src/main/java/io/flexwork/modules/audit/AuditLogUpdateEvent.java

@@ -0,0 +1,15 @@
+package io.flexwork.modules.audit;
+
+import lombok.Getter;
+import org.springframework.context.ApplicationEvent;
+
+@Getter
+public class AuditLogUpdateEvent extends ApplicationEvent {
+
+    private final Object updatedEntity;
+
+    public AuditLogUpdateEvent(Object source, Object updatedEntity) {
+        super(source);
+        this.updatedEntity = updatedEntity;
+    }
+}

server/src/main/java/io/flexwork/modules/audit/AuditLogUpdateEventListener.java

@@ -0,0 +1,169 @@
+package io.flexwork.modules.audit;
+
+import io.flexwork.modules.collab.domain.ActivityLog;
+import io.flexwork.modules.collab.domain.EntityType;
+import io.flexwork.modules.collab.repository.ActivityLogRepository;
+import io.flexwork.security.SecurityUtils;
+import jakarta.persistence.EntityNotFoundException;
+import java.lang.reflect.Field;
+import java.lang.reflect.Method;
+import java.util.List;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.context.ApplicationContext;
+import org.springframework.context.event.EventListener;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.scheduling.annotation.Async;
+import org.springframework.stereotype.Component;
+import org.springframework.transaction.annotation.Transactional;
+
+@Component
+public class AuditLogUpdateEventListener {
+
+    private static final Logger LOG = LoggerFactory.getLogger(AuditLogUpdateEventListener.class);
+
+    private final ActivityLogRepository activityLogRepository;
+    private final EntityFieldHandlerRegistryFactory registryFactory;
+    private final ApplicationContext applicationContext;
+
+    public AuditLogUpdateEventListener(
+            ActivityLogRepository activityLogRepository,
+            EntityFieldHandlerRegistryFactory registryFactory,
+            ApplicationContext applicationContext) {
+        this.activityLogRepository = activityLogRepository;
+        this.registryFactory = registryFactory;
+        this.applicationContext = applicationContext;
+    }
+
+    @Async("auditLogExecutor")
+    @Transactional
+    @EventListener
+    public void onNewTeamRequestCreated(AuditLogUpdateEvent event) {
+        try {
+
+            Object updatedEntity = event.getUpdatedEntity();
+            Class<?> entityClass = updatedEntity.getClass();
+            Long entityId = extractEntityId(updatedEntity);
+
+            // Fetch the existing entity
+            Object existingEntity = fetchExistingEntity(entityClass, entityId);
+
+            // Convert existing entity to DTO form using the mapper
+            Object existingEntityDto = mapEntityToDto(existingEntity.getClass(), existingEntity);
+
+            // Get the registry for the entity
+            EntityFieldHandlerRegistry registry = registryFactory.getRegistry(entityClass);
+
+            // Find changes between the existing DTO and updated entity
+            List<AuditUtils.FieldChange> changes =
+                    AuditUtils.findChanges(existingEntityDto, updatedEntity, registry);
+
+            if (!changes.isEmpty()) {
+                // Generate HTML content
+                String htmlLog = ActivityLogUtils.generateHtmlLog(changes);
+
+                // Save the aggregated activity log
+                saveActivityLog(registry.getEntityType(), entityId, htmlLog);
+            }
+        } catch (Exception e) {
+            // Log the exception
+            LOG.error("Error in async logEntityChanges", e);
+        }
+    }
+
+    private Object mapEntityToDto(Class<?> entityClass, Object entity) {
+        try {
+            // Derive the mapper bean name based on conventions (e.g., "teamMapper")
+            String mapperBeanName = getMapperBeanName(entityClass);
+
+            // Fetch the mapper bean from the Spring context
+            Object mapper = applicationContext.getBean(mapperBeanName);
+
+            // Find the "toDto" method in the mapper
+            Method toDtoMethod = mapper.getClass().getDeclaredMethod("toDto", entityClass);
+
+            // Invoke the "toDto" method and return the result
+            return toDtoMethod.invoke(mapper, entity);
+        } catch (Exception e) {
+            throw new RuntimeException(
+                    "Failed to map entity to DTO for class: " + entityClass.getSimpleName(), e);
+        }
+    }
+
+    private String getMapperBeanName(Class<?> entityClass) {
+        // Get the simple name of the entity class
+        String entityName = entityClass.getSimpleName();
+
+        // Remove the "DTO" suffix if it exists
+        if (entityName.endsWith("DTO")) {
+            entityName = entityName.substring(0, entityName.length() - 3);
+        }
+
+        // Convert the entity name to the mapper bean name
+        String mapperBeanName =
+                Character.toLowerCase(entityName.charAt(0))
+                        + entityName.substring(1)
+                        + "MapperImpl";
+
+        return mapperBeanName;
+    }
+
+    private void saveActivityLog(EntityType entityType, Long entityId, String activityDetails) {
+        ActivityLog activityLog = new ActivityLog();
+        activityLog.setEntityType(entityType);
+        activityLog.setEntityId(entityId);
+        activityLog.setContent(activityDetails);
+        activityLog.setCreatedBy(SecurityUtils.getCurrentUserAuditorLogin());
+        activityLogRepository.save(activityLog);
+    }
+
+    private Object fetchExistingEntity(Class<?> entityClass, Long entityId) {
+        // Get the repository bean name for the entity
+        String repositoryBeanName = getRepositoryBeanName(entityClass);
+
+        // Fetch the repository dynamically
+        JpaRepository<?, Long> repository =
+                (JpaRepository<?, Long>) applicationContext.getBean(repositoryBeanName);
+
+        // Query the existing entity by ID
+        return repository
+                .findById(entityId)
+                .orElseThrow(
+                        () ->
+                                new EntityNotFoundException(
+                                        "Entity of class "
+                                                + entityClass.getSimpleName()
+                                                + " with ID "
+                                                + entityId
+                                                + " not found"));
+    }
+
+    private String getRepositoryBeanName(Class<?> entityClass) {
+        // Get the simple name of the entity class
+        String entityName = entityClass.getSimpleName();
+
+        // Remove "DTO" suffix if present
+        if (entityName.endsWith("DTO")) {
+            entityName = entityName.substring(0, entityName.length() - 3);
+        }
+
+        // Convert the entity name to the repository bean name
+        // Convention: repositoryBeanName = entityName (lowerCamelCase) + "Repository"
+        String repositoryBeanName =
+                Character.toLowerCase(entityName.charAt(0))
+                        + entityName.substring(1)
+                        + "Repository";
+
+        return repositoryBeanName;
+    }
+
+    private Long extractEntityId(Object entity) {
+        try {
+            Field idField = entity.getClass().getDeclaredField("id");
+            idField.setAccessible(true);
+            return (Long) idField.get(entity);
+        } catch (NoSuchFieldException | IllegalAccessException e) {
+            throw new RuntimeException("Failed to extract entity ID", e);
+        }
+    }
+}