Flowable-HelloWorld

cmyang2021-11-202023-05-14

简介

轻量级工作流引擎，使用Java编写，Flowable是Activiti的fork

github地址：https://github.com/flowable/flowable-engine

开源文档：https://wwv.flowable.com/open-source/docs/bpmn/ch02-GettingStarted/

6.5.0版本中文文档：https://jeesite.gitee.io/front/flowable/6.5.0/bpmn/index.html

Hello World

Gitee地址：https://gitee.com/aacopy/flowable-learn.git

创建一个spring boot项目

需要加入 spring web，

本示例，spring boot 2.6.1，flowable 6.7.1， mysql 5.7

创建数据库

新建一个mysql数据库，名称为flowable_learn

编写示例

加入maven依赖

<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
</dependency>
<dependency>
    <groupId>org.flowable</groupId>
    <artifactId>flowable-spring-boot-starter</artifactId>
    <version>6.7.1</version>
</dependency>

在application.properties新增配置项

server.servlet.context-path=/flowable-learn

spring.datasource.url=jdbc:mysql://127.0.0.1:3306/flowable_learn?characterEncoding=UTF-8
spring.datasource.username=root
spring.datasource.password=123456

此处有坑：

如果启动服务，报错找不到flowable的表

原因：使用root用户登录，程序检测到该用户下的其他数据库中有flowable相关的表，就不再创建表了，但是在使用的时候又找不到表。

解决：在url后面追加&nullCatalogMeansCurrent=true

1	spring.datasource.url=jdbc:mysql://127.0.0.1:3306/flowable_learn?characterEncoding=UTF-8&nullCatalogMeansCurrent=true

在resources文件夹下新建文件夹processes
创建一个流程文件hello-world.bpmn20.xml，复制以下内容到文件

<?xml version="1.0" encoding="UTF-8"?>
<definitions xmlns="http://www.omg.org/spec/BPMN/20100524/MODEL" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:flowable="http://flowable.org/bpmn" xmlns:bpmndi="http://www.omg.org/spec/BPMN/20100524/DI" xmlns:omgdc="http://www.omg.org/spec/DD/20100524/DC" xmlns:omgdi="http://www.omg.org/spec/DD/20100524/DI" xmlns:xsd="http://www.w3.org/2001/XMLSchema" targetNamespace="http://flowable.org/test" exporter="Flowable Open Source Modeler" exporterVersion="1.1.0-SNAPSHOT">
    <process id="helloWorldProcess" name="Hello World Process">
        <startEvent id="theStart" />
        <sequenceFlow id="flow1" sourceRef="theStart" targetRef="theTask" />
        <userTask id="theTask" name="my task" flowable:assignee="aacopy" />
        <sequenceFlow id="flow2" sourceRef="theTask" targetRef="theEnd" />
        <endEvent id="theEnd" />
    </process>
    <bpmndi:BPMNDiagram id="BPMNDiagram_helloWorldProcess">
        <bpmndi:BPMNPlane id="BPMNPlane_helloWorldProcess" bpmnElement="helloWorldProcess">
            <bpmndi:BPMNEdge id="flow1_di" bpmnElement="flow1">
                <omgdi:waypoint x="130" y="178" />
                <omgdi:waypoint x="180" y="178" />
            </bpmndi:BPMNEdge>
            <bpmndi:BPMNEdge id="flow2_di" bpmnElement="flow2">
                <omgdi:waypoint x="280" y="178" />
                <omgdi:waypoint x="332" y="178" />
            </bpmndi:BPMNEdge>
            <bpmndi:BPMNShape id="BPMNShape_theStart" bpmnElement="theStart">
                <omgdc:Bounds x="100" y="163" width="30" height="30" />
            </bpmndi:BPMNShape>
            <bpmndi:BPMNShape id="theTask_di" bpmnElement="theTask">
                <omgdc:Bounds x="180" y="138" width="100" height="80" />
            </bpmndi:BPMNShape>
            <bpmndi:BPMNShape id="theEnd_di" bpmnElement="theEnd">
                <omgdc:Bounds x="332" y="160" width="36" height="36" />
            </bpmndi:BPMNShape>
        </bpmndi:BPMNPlane>
    </bpmndi:BPMNDiagram>
</definitions>

编写HelloWorldController类

package cn.aacopy.learn.flowable;

import org.flowable.common.engine.impl.util.IoUtil;
import org.flowable.engine.RepositoryService;
import org.flowable.engine.RuntimeService;
import org.flowable.engine.TaskService;
import org.flowable.engine.repository.ProcessDefinition;
import org.flowable.task.api.Task;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.MediaType;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.InputStream;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

/**
 * @author iseven.yang
 * @date 2021/12/2 15:40
 */
@RestController
@RequestMapping("/helloWorld")
public class HelloWorldController {

    @Autowired
    private RuntimeService runtimeService;

    @Autowired
    private TaskService taskService;

    @Autowired
    private RepositoryService repositoryService;

    /**
     * 查看流程图
     * @param response
     * @throws IOException
     */
    @RequestMapping("/image")
    public void image(HttpServletResponse response) throws IOException {
        ProcessDefinition processDefinition = repositoryService.createProcessDefinitionQuery()
                .processDefinitionKey("helloWorldProcess").latestVersion().singleResult();
        InputStream imageStream = repositoryService.getProcessDiagram(processDefinition.getId());
        byte[] data = IoUtil.readInputStream(imageStream, "image inputStream name");
        response.setContentType(MediaType.IMAGE_PNG_VALUE);
        response.getOutputStream().write(data);
    }

    /**
     * 启动流程
     * @return
     */
    @RequestMapping("/start")
    public String start() {
        runtimeService.startProcessInstanceByKey("helloWorldProcess");
        return "success";
    }

    /**
     * 获取待办列表
     * @param assignee
     * @return
     */
    @RequestMapping("/todo")
    public List<Map<String, Object>> todo(String assignee) {
        List<Task> list = taskService.createTaskQuery()
                .taskAssignee(assignee).orderByTaskCreateTime().desc().list();
        return list.stream().map(task -> {
            Map<String, Object> taskMap = new HashMap<>();
            taskMap.put("id", task.getId());
            taskMap.put("name", task.getName());
            taskMap.put("createTime", task.getCreateTime());
            return taskMap;
        }).collect(Collectors.toList());
    }

    /**
     * 提交任务
     * @param taskId
     * @return
     */
    @RequestMapping("/complete")
    public String complete(String taskId) {
        taskService.complete(taskId);
        return "success";
    }
    
}