整合Activiti Modeler到业务系统（或BPM平台）
1. 为什么要整合
Activiti 5.10版本把原本独立的Activiti Modeler模块整合到了Activiti Explorer中，两者相结合使用起来很方便，通过Modeler设计的流程模型可以直接部署到引擎，也可以把已经部署的流程转换为Model从而在Modeler中编辑。
在实际应用中也有这样的需求，把Modeler整合到业务系统中可以供管理员使用，或者作为BPM平台的一部分存在，很遗憾官方没有给出如何整合Modeler的文档。
2. 整合工作
2.1 下载源码
首先需要从Github下载源码：https://github.com/Activiti/Activiti；可以直接用Git克隆，也可以下载zip格式的压缩包。
2.2 复制文件
复制的所有文件均在activiti-webapp-explorer2目录中。
- src/main/resources中的editor.html、stencilset.json、plugins.xml到项目源码的源码根目录，保证编译之后在classes根目录
- src/main/webapp中的api、editor、explorer、libs到项目的webapp目录（与WEB-INF目录同级）
2.3 添加依赖
<dependency>
<groupId>org.activiti</groupId>
<artifactId>activiti-explorer</artifactId>
<version>5.14</version>
<exclusions>
<exclusion>
<artifactId>vaadin</artifactId>
<groupId>com.vaadin</groupId>
</exclusion>
<exclusion>
<artifactId>dcharts-widget</artifactId>
<groupId>org.vaadin.addons</groupId>
</exclusion>
<exclusion>
<artifactId>activiti-simple-workflow</artifactId>
<groupId>org.activiti</groupId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>org.activiti</groupId>
<artifactId>activiti-modeler</artifactId>
<version>5.14</version>
</dependency>
2.4 添加Java类
添加一个ExplorerRestApplication.java类保存到项目中，注册了一些REST路由。
package org.activiti.explorer.rest.application;
import org.activiti.editor.rest.application.ModelerServicesInit;
import org.activiti.rest.api.DefaultResource;
import org.activiti.rest.application.ActivitiRestApplication;
import org.activiti.rest.filter.JsonpFilter;
import org.restlet.Restlet;
import org.restlet.routing.Router;
public class ExplorerRestApplication extends ActivitiRestApplication {
public ExplorerRestApplication() {
super();
}
/**
* Creates a root Restlet that will receive all incoming calls.
*/
@Override
public synchronized Restlet createInboundRoot() {
Router router = new Router(getContext());
router.attachDefault(DefaultResource.class);
ModelerServicesInit.attachResources(router);
DiagramServicesInit.attachResources(router);
JsonpFilter jsonpFilter = new JsonpFilter(getContext());
jsonpFilter.setNext(router);
return jsonpFilter;
}
}
2.5 配置web.xml
在web.xml文件中添加如下配置：
<!-- Restlet adapter, used to expose modeler functionality through REST -->
<servlet>
<servlet-name>RestletServlet</servlet-name>
<servlet-class>org.restlet.ext.servlet.ServerServlet</servlet-class>
<init-param>
<!-- Application class name -->
<param-name>org.restlet.application</param-name>
<param-value>org.activiti.explorer.rest.application.ExplorerRestApplication</param-value>
</init-param>
</servlet>
<!-- Catch all service requests -->
<servlet-mapping>
<servlet-name>RestletServlet</servlet-name>
<url-pattern>/service/*</url-pattern>
</servlet-mapping>
2.6 控制器
使用Spring MVC做了一个简单的封装，也可以使用其他的MVC实现。
package me.kafeitu.demo.activiti.web.workflow;
import java.io.ByteArrayInputStream;
import java.util.List;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.activiti.bpmn.converter.BpmnXMLConverter;
import org.activiti.bpmn.model.BpmnModel;
import org.activiti.editor.constants.ModelDataJsonConstants;
import org.activiti.editor.language.json.converter.BpmnJsonConverter;
import org.activiti.engine.RepositoryService;
import org.activiti.engine.repository.Deployment;
import org.activiti.engine.repository.Model;
import org.apache.commons.io.IOUtils;
import org.apache.commons.lang3.StringUtils;
import org.codehaus.jackson.JsonNode;
import org.codehaus.jackson.map.ObjectMapper;
import org.codehaus.jackson.node.ObjectNode;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.mvc.support.RedirectAttributes;
/**
* 流程模型控制器
*
* @author henryyan
*/
@Controller
@RequestMapping(value = "/workflow/model")
public class ModelController {
protected Logger logger = LoggerFactory.getLogger(getClass());
@Autowired
RepositoryService repositoryService;
/**
* 模型列表
*/
@RequestMapping(value = "list")
public ModelAndView modelList() {
ModelAndView mav = new ModelAndView("workflow/model-list");
List<Model> list = repositoryService.createModelQuery().list();
mav.addObject("list", list);
return mav;
}
/**
* 创建模型
*/
@RequestMapping(value = "create")
public void create(@RequestParam("name") String name, @RequestParam("key") String key, @RequestParam("description") String description,
HttpServletRequest request, HttpServletResponse response) {
try {
ObjectMapper objectMapper = new ObjectMapper();
ObjectNode editorNode = objectMapper.createObjectNode();
editorNode.put("id", "canvas");
editorNode.put("resourceId", "canvas");
ObjectNode stencilSetNode = objectMapper.createObjectNode();
stencilSetNode.put("namespace", "http://b3mn.org/stencilset/bpmn2.0#");
editorNode.put("stencilset", stencilSetNode);
Model modelData = repositoryService.newModel();
ObjectNode modelObjectNode = objectMapper.createObjectNode();
modelObjectNode.put(ModelDataJsonConstants.MODEL_NAME, name);
modelObjectNode.put(ModelDataJsonConstants.MODEL_REVISION, 1);
description = StringUtils.defaultString(description);
modelObjectNode.put(ModelDataJsonConstants.MODEL_DESCRIPTION, description);
modelData.setMetaInfo(modelObjectNode.toString());
modelData.setName(name);
modelData.setKey(StringUtils.defaultString(key));
repositoryService.saveModel(modelData);
repositoryService.addModelEditorSource(modelData.getId(), editorNode.toString().getBytes("utf-8"));
response.sendRedirect(request.getContextPath() + "/service/editor?id=" + modelData.getId());
} catch (Exception e) {
logger.error("创建模型失败：", e);
}
}
/**
* 根据Model部署流程
*/
@RequestMapping(value = "deploy/{modelId}")
public String deploy(@PathVariable("modelId") String modelId, RedirectAttributes redirectAttributes) {
try {
Model modelData = repositoryService.getModel(modelId);
ObjectNode modelNode = (ObjectNode) new ObjectMapper().readTree(repositoryService.getModelEditorSource(modelData.getId()));
byte[] bpmnBytes = null;
BpmnModel model = new BpmnJsonConverter().convertToBpmnModel(modelNode);
bpmnBytes = new BpmnXMLConverter().convertToXML(model);
String processName = modelData.getName() + ".bpmn20.xml";
Deployment deployment = repositoryService.createDeployment().name(modelData.getName()).addString(processName, new String(bpmnBytes)).deploy();
redirectAttributes.addFlashAttribute("message", "部署成功，部署ID=" + deployment.getId());
} catch (Exception e) {
logger.error("根据模型部署流程失败：modelId={}", modelId, e);
}
return "redirect:/workflow/model/list";
}
/**
* 导出model的xml文件
*/
@RequestMapping(value = "export/{modelId}")
public void export(@PathVariable("modelId") String modelId, HttpServletResponse response) {
try {
Model modelData = repositoryService.getModel(modelId);
BpmnJsonConverter jsonConverter = new BpmnJsonConverter();
JsonNode editorNode = new ObjectMapper().readTree(repositoryService.getModelEditorSource(modelData.getId()));
BpmnModel bpmnModel = jsonConverter.convertToBpmnModel(editorNode);
BpmnXMLConverter xmlConverter = new BpmnXMLConverter();
byte[] bpmnBytes = xmlConverter.convertToXML(bpmnModel);
ByteArrayInputStream in = new ByteArrayInputStream(bpmnBytes);
IOUtils.copy(in, response.getOutputStream());
String filename = bpmnModel.getMainProcess().getId() + ".bpmn20.xml";
response.setHeader("Content-Disposition", "attachment; filename=" + filename);
response.flushBuffer();
} catch (Exception e) {
logger.error("导出model的xml文件失败：modelId={}", modelId, e);
}
}
}
2.7 注意事项
如果使用Spring代理引擎，并且在项目中同时有activiti.cfg.xml文件（不管在main/resources还是test/resources目录），在activiti.cfg.xml里面的引擎中添加下面的配置参数，否则会导致打开Modeler的编辑页面时读取数据返回204状态码。
<property name="processEngineName" value="test"></property>
引擎默认名称为default，ProcessEngines.getDefaultProcessEngine()查询时会先检索main/resources，然后再检索test/resources的activiti.cfg.xml和activiti-context.xml文件，所以当main/resources监测不到指定文件时就会导致该引擎被当做web应用的引擎对象，这样会导致有两个引擎，所以把引擎的名称改为非默认的“default”。
3. 中文乱码问题解决办法
在JVM参数中添加参数：
-Dsun.jnu.encoding=UTF-8 -Dfile.encoding=UTF-8
参考：在Activiti Modeler中设计的流程包含奇数个中文时不能部署问题
4. 效果截图
在最新的kft-activiti-demo版本（1.7.0）中已经集成了Activiti Modeler，可以在线访问，也可以下载源码学习如何配置。
登录http://demo.kafeitu.me/kft-activiti-demo后选择流程管理->模型工作区菜单项即可。
