VUE+bpmn.js实现工作流

1、安装bpmn.js

npm install bpmn-js@7.3.1   // 我安装的版本是7.3.1

npm install bpmn-js-properties-panel@0.37.2

npm install bpmn-moddle@7.1.3   

npm install --save camunda-bpmn-moddle

2、配置axios，在main.js中引入axios

import axios from 'axios'

Vue.prototype.$http = axios

3、bpmn汉化，创建defaultXmlStr.js（是初始化的xml文件）、customTranslate.js和translations.js文件，可从网上下载，也可自行新建，目录如下

defaultXmlStr.js内容如下，若将 <startEvent id="StartEvent" name="开始" />去掉，则初始化的页面是空白页

export var defaultXmlStr = `xml <?xml version="1.0" encoding="UTF-8"?>
<definitions xmlns="http://www.omg.org/spec/BPMN/20100524/MODEL" xmlns:bpmndi="http://www.omg.org/spec/BPMN/20100524/DI" xmlns:omgdc="http://www.omg.org/spec/DD/20100524/DC" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:camunda="http://camunda.org/schema/1.0/bpmn" id="sid-38422fae-e03e-43a3-bef4-bd33b32041b2" targetNamespace="http://bpmn.io/bpmn" exporter="bpmn-js (https://demo.bpmn.io)" exporterVersion="5.1.2">
  <process id="Process" name="默认模板" isExecutable="true" camunda:versionTag="0.0.1">
    <startEvent id="StartEvent" name="开始" />
  </process>
  <bpmndi:BPMNDiagram id="BpmnDiagram_1">
    <bpmndi:BPMNPlane id="BpmnPlane_1" bpmnElement="Process">
      <bpmndi:BPMNShape id="StartEvent_1y45yut_di" bpmnElement="StartEvent">
        <omgdc:Bounds x="152" y="102" width="36" height="36" />
        <bpmndi:BPMNLabel>
          <omgdc:Bounds x="160" y="145" width="22" height="14" />
        </bpmndi:BPMNLabel>
      </bpmndi:BPMNShape>
    </bpmndi:BPMNPlane>
  </bpmndi:BPMNDiagram>
</definitions>`

translations.js内容如下：

/**
 * This is a sample file that should be replaced with the actual translation.
 *
 * Checkout https://github.com/bpmn-io/bpmn-js-i18n for a list of available
 * translations and labels to translate.
 */
export default {
  'Activate the global connect tool': '激活全局连接工具',
  'Append {type}': '添加 {type}',
  'Add Lane above': '在上面添加道',
  'Divide into two Lanes': '分割成两个道',
  'Divide into three Lanes': '分割成三个道',
  'Add Lane below': '在下面添加道',
  'Append compensation activity': '追加补偿活动',
  'Change type': '修改类型',
  'Connect using Association': '使用关联连接',
  'Connect using Sequence/MessageFlow or Association': '使用顺序/消息流或者关联连接',
  'Connect using DataInputAssociation': '使用数据输入关联连接',
  Remove: '移除',
  'Activate the hand tool': '激活抓手工具',
  'Activate the lasso tool': '激活套索工具',
  'Activate the create/remove space tool': '激活创建/删除空间工具',
  'Create expanded SubProcess': '创建扩展子过程',
  'Create IntermediateThrowEvent/BoundaryEvent': '创建中间抛出事件/边界事件',
  'Create Pool/Participant': '创建池/参与者',
  'Parallel Multi Instance': '并行多重事件',
  'Sequential Multi Instance': '时序多重事件',
  DataObjectReference: '数据对象参考',
  DataStoreReference: '数据存储参考',
  Loop: '循环',
  'Ad-hoc': '即席',
  'Create {type}': '创建 {type}',
  Task: '任务',
  'Send Task': '发送任务',
  'Receive Task': '接收任务',
  'User Task': '用户任务',
  'Manual Task': '手工任务',
  'Business Rule Task': '业务规则任务',
  'Service Task': '服务任务',
  'Script Task': '脚本任务',
  'Call Activity': '调用活动',
  'Sub Process (collapsed)': '子流程（折叠的）',
  'Sub Process (expanded)': '子流程（展开的）',
  'Start Event': '开始事件',
  StartEvent: '开始事件',
  'Intermediate Throw Event': '中间事件',
  'End Event': '结束事件',
  EndEvent: '结束事件',
  'Create Gateway': '创建网关',
  'Create Intermediate/Boundary Event': '创建中间/边界事件',
  'Message Start Event': '消息开始事件',
  'Timer Start Event': '定时开始事件',
  'Conditional Start Event': '条件开始事件',
  'Signal Start Event': '信号开始事件',
  'Error Start Event': '错误开始事件',
  'Escalation Start Event': '升级开始事件',
  'Compensation Start Event': '补偿开始事件',
  'Message Start Event (non-interrupting)': '消息开始事件（非中断）',
  'Timer Start Event (non-interrupting)': '定时开始事件（非中断）',
  'Conditional Start Event (non-interrupting)': '条件开始事件（非中断）',
  'Signal Start Event (non-interrupting)': '信号开始事件（非中断）',
  'Escalation Start Event (non-interrupting)': '升级开始事件（非中断）',
  'Message Intermediate Catch Event': '消息中间捕获事件',
  'Message Intermediate Throw Event': '消息中间抛出事件',
  'Timer Intermediate Catch Event': '定时中间捕获事件',
  'Escalation Intermediate Throw Event': '升级中间抛出事件',
  'Conditional Intermediate Catch Event': '条件中间捕获事件',
  'Link Intermediate Catch Event': '链接中间捕获事件',
  'Link Intermediate Throw Event': '链接中间抛出事件',
  'Compensation Intermediate Throw Event': '补偿中间抛出事件',
  'Signal Intermediate Catch Event': '信号中间捕获事件',
  'Signal Intermediate Throw Event': '信号中间抛出事件',
  'Message End Event': '消息结束事件',
  'Escalation End Event': '定时结束事件',
  'Error End Event': '错误结束事件',
  'Cancel End Event': '取消结束事件',
  'Compensation End Event': '补偿结束事件',
  'Signal End Event': '信号结束事件',
  'Terminate End Event': '终止结束事件',
  'Message Boundary Event': '消息边界事件',
  'Message Boundary Event (non-interrupting)': '消息边界事件（非中断）',
  'Timer Boundary Event': '定时边界事件',
  'Timer Boundary Event (non-interrupting)': '定时边界事件（非中断）',
  'Escalation Boundary Event': '升级边界事件',
  'Escalation Boundary Event (non-interrupting)': '升级边界事件（非中断）',
  'Conditional Boundary Event': '条件边界事件',
  'Conditional Boundary Event (non-interrupting)': '条件边界事件（非中断）',
  'Error Boundary Event': '错误边界事件',
  'Cancel Boundary Event': '取消边界事件',
  'Signal Boundary Event': '信号边界事件',
  'Signal Boundary Event (non-interrupting)': '信号边界事件（非中断）',
  'Compensation Boundary Event': '补偿边界事件',
  'Exclusive Gateway': '互斥网关',
  'Parallel Gateway': '并行网关',
  'Inclusive Gateway': '相容网关',
  'Complex Gateway': '复杂网关',
  'Event based Gateway': '事件网关',
  Transaction: '转运',
  'Sub Process': '子流程',
  'Event Sub Process': '事件子流程',
  'Collapsed Pool': '折叠池',
  'Expanded Pool': '展开池',
  // Errors
  'no parent for {element} in {parent}': '在{parent}里，{element}没有父类',
  'no shape type specified': '没有指定的形状类型',
  'flow elements must be children of pools/participants': '流元素必须是池/参与者的子类',
  'out of bounds release': '越界释放',
  'more than {count} child lanes': '子道大于{count} ',
  'element required': '元素不能为空',
  'diagram not part of bpmn:Definitions': '流程图不符合bpmn规范',
  'no diagram to display': '没有可展示的流程图',
  'no process or collaboration to display': '没有可展示的流程/协作',
  'element {element} referenced by {referenced}#{property} not yet drawn': '由{referenced}#{property}引用的{element}元素仍未绘制',
  'already rendered {element}': '{element} 已被渲染',
  'failed to import {element}': '导入{element}失败',
  // 属性面板的参数
  Id: 'KEY',
  Name: '名称',
  General: '常规',
  Details: '详情',
  'Message Name': '消息名称',
  Message: '消息',
  Initiator: '创建者',
  'Asynchronous Continuations': '持续异步',
  'Asynchronous Before': '异步前',
  'Asynchronous After': '异步后',
  'Job Configuration': '工作配置',
  Exclusive: '排除',
  'Job Priority': '工作优先级',
  'Retry Time Cycle': '重试时间周期',
  Documentation: '文档',
  'Element Documentation': '元素文档',
  'History Configuration': '历史配置',
  'History Time To Live': '历史的生存时间',
  Forms: '表单',
  'Form Key': '表单key',
  'Form Fields': '表单字段',
  'Business Key': '业务key',
  'Form Field': '表单字段',
  ID: '编号',
  Type: '类型',
  Label: '名称',
  'Default Value': '默认值',
  Validation: '校验',
  'Add Constraint': '添加约束',
  Config: '配置',
  Properties: '属性',
  'Add Property': '添加属性',
  Value: '值',
  Listeners: '监听器',
  'Execution Listener': '执行监听',
  'Event Type': '事件类型',
  'Listener Type': '监听器类型',
  'Java Class': 'Java类',
  Expression: '表达式',
  'Must provide a value': '必须提供一个值',
  'Delegate Expression': '代理表达式',
  Script: '脚本',
  'Script Format': '脚本格式',
  'Script Type': '脚本类型',
  'Inline Script': '内联脚本',
  'External Script': '外部脚本',
  Resource: '资源',
  'Field Injection': '字段注入',
  Extensions: '扩展',
  'Input/Output': '输入/输出',
  'Input Parameters': '输入参数',
  'Output Parameters': '输出参数',
  Parameters: '参数',
  'Output Parameter': '输出参数',
  'Timer Definition Type': '定时器定义类型',
  'Timer Definition': '定时器定义',
  Date: '日期',
  Duration: '持续',
  Cycle: '循环',
  Signal: '信号',
  'Signal Name': '信号名称',
  Escalation: '升级',
  Error: '错误',
  'Link Name': '链接名称',
  Condition: '条件名称',
  'Variable Name': '变量名称',
  'Variable Event': '变量事件',
  'Specify more than one variable change event as a comma separated list.': '多个变量事件以逗号隔开',
  'Wait for Completion': '等待完成',
  'Activity Ref': '活动参考',
  'Version Tag': '版本标签',
  Executable: '可执行文件',
  'External Task Configuration': '扩展任务配置',
  'Task Priority': '任务优先级',
  External: '外部',
  Connector: '连接器',
  'Must configure Connector': '必须配置连接器',
  'Connector Id': '连接器编号',
  Implementation: '实现方式',
  'Field Injections': '字段注入',
  Fields: '字段',
  'Result Variable': '结果变量',
  Topic: '主题',
  'Configure Connector': '配置连接器',
  'Input Parameter': '输入参数',
  Assignee: '代理人',
  'Candidate Users': '候选用户',
  'Candidate Groups': '候选组',
  'Due Date': '到期时间',
  'Follow Up Date': '跟踪日期',
  Priority: '优先级',
  Variables: '变量',
  'This maps to the process definition key.': '同时会映射为流程定义Key',
  'Element must have an unique id.': '元素必须有唯一的Key',
  'Id must be a valid QName.': 'Key不合法',
  'Candidate Starter Configuration': '候选人起动器配置',
  'Candidate Starter Groups': '候选人起动器组',
  'Specify more than one group as a comma separated list.': '多个组使用英文逗号隔开',
  'Candidate Starter Users': '允许发起流程的用户ID',
  'Specify more than one user as a comma separated list.': '多个用户使用英文逗号隔开',
  'Tasklist Configuration': '任务列表配置',
  Startable: '可启动',
  'Available process variables, identified in the diagram.': '在流程图中指定的变量',
  'No variables found.': '没有发现变量',
  'This maps to the task definition key.': '映射到任务定义键',
  'No variables defined.': '没有定义变量',
  'The follow up date as an EL expression (e.g. ${someDate} or an ISO date (e.g. 2015-06-26T09:54:00)':
    '跟踪日期必须符合EL表达式，如： ${someDate} ,或者一个ISO标准日期，如：2015-06-26T09:54:00',
  'The due date as an EL expression (e.g. ${someDate} or an ISO date (e.g. 2015-06-26T09:54:00)':
    '跟踪日期必须符合EL表达式，如： ${someDate} ,或者一个ISO标准日期，如：2015-06-26T09:54:00',
}

customTranslate.js内容如下：

import translations from './translations'
export default function customTranslate(template, replacements) {
  replacements = replacements || {}
  // Translate
  template = translations[template] || template
  // Replace
  return template.replace(/{([^}]+)}/g, function (_, key) {
    return replacements[key] || '{' + key + '}'
  })
}

3、构建一个简单的vue页面

<template>
  <div class="containers" ref="content">
    <a-space>
      <el-button @click="downloadBpmn">
        <a-icon type="download" />
        保存BPMN
      </el-button>
      <el-button @click="downloadSvg">
        <a-icon type="download" />
        保存SVG
      </el-button>

      <a-upload :file-list="uploadBpmnFileList" :before-upload="beforeUpload">
        <el-button>
          <a-icon type="upload" />
          导入BPMN
        </el-button>
      </a-upload>

      <el-button-group>
        <el-button @click="handlerUndo">撤销</el-button>
        <el-button @click="handlerRedo">恢复</el-button>
      </el-button-group>

      <el-button-group>
        <el-button @click="handlerZoom(0.1)">放大</el-button>
        <el-button @click="handlerZoom(-0.1)">缩小</el-button>
        <el-button @click="handlerZoom(0)">还原</el-button>
      </el-button-group>

      <a hidden ref="downloadLink"></a>
    </a-space>

    <div class="canvas" ref="canvas"></div>
    <div id="js-properties-panel" class="panel"></div>
  </div>
</template>

<script>
import BpmnModeler from 'bpmn-js/lib/Modeler'

import propertiesPanelModule from 'bpmn-js-properties-panel'
import propertiesProviderModule from 'bpmn-js-properties-panel/lib/provider/bpmn'
import bpmnModdleDescriptor from 'bpmn-moddle/resources/bpmn/json/bpmn.json'

// BPMN国际化
import customTranslate from './customTranslate/customTranslate'

import { defaultXmlStr } from './defaultXmlStr'

// 自定义汉化模块
var customTranslateModule = {
  translate: ['value', customTranslate],
}

export default {
  components: {},
  data() {
    return {
      bpmnModeler: null,
      container: null,
      canvas: null,

      uploadBpmnFileList: [],
      scale: 1,
    }
  },
  created() {},
  mounted() {
    this.init()
  },
  methods: {
    /**
     * 初始化流程设计器对象
     * @returns {Promise<void>}
     */
    async init() {
      // xmlStr 是现有的图，defaultXmlStr是默认只有开始的图
      this.xmlStr = await this.getXmlUrl()
      this.$nextTick(() => {
        this.initBpmn()
      })
    },
    async initBpmn() {
      // 获取到属性ref为“content”的dom节点
      this.container = this.$refs.content
      // 获取到属性ref为“canvas”的dom节点
      const canvas = this.$refs.canvas
      // 创建BpmnModeler
      this.bpmnModeler = new BpmnModeler({
        container: canvas,
        // 加入工具栏支持
        propertiesPanel: {
          parent: '#js-properties-panel',
        },
        additionalModules: [
          // 左边工具栏以及节点
          propertiesProviderModule,
          // 右边的工具栏
          propertiesPanelModule,
          // 国际化
          customTranslateModule,
        ],
        moddleExtensions: {
          bpmn: bpmnModdleDescriptor,
        },
      })
      // 创建新流程
      await this.createNewDiagram(defaultXmlStr)
    },

    getXmlUrl() {
      let diagramUrl = 'https://hexo-blog-1256114407.cos.ap-shenzhen-fsi.myqcloud.com/mock1.bpmn'
      return new Promise(resolve => {
        this.$http.get(diagramUrl).then(function (res) {
          resolve(res.data)
        })
      })
    },
    /**
     * 创建新流程
     * @param bpmn BPMN流程XML报文
     * @returns {Promise<void>}
     */
    async createNewDiagram(bpmn) {
      // 将字符串转换成图显示出来;
      this.bpmnModeler.importXML(bpmn, err => {
        if (err) {
          this.$message.error('打开模型出错,请确认该模型符合Bpmn2.0规范')
        } else {
          console.log('成功导入模型')
        }
      })
    },

    handlerRedo() {
      this.bpmnModeler.get('commandStack').redo()
    },
    handlerUndo() {
      this.bpmnModeler.get('commandStack').undo()
    },
    handlerZoom(radio) {
      const newScale = !radio ? 1.0 : this.scale + radio
      this.bpmnModeler.get('canvas').zoom(newScale)
      this.scale = newScale
    },

    beforeUpload(file) {
      // this.uploadBpmnFileList = [];
      this.openBpmn(file)
      return false
    },

    openBpmn(file) {
      const reader = new FileReader()
      // 读取File对象中的文本信息，编码格式为UTF-8
      reader.readAsText(file, 'utf-8')
      reader.onload = () => {
        // 读取完毕后将文本信息导入到Bpmn建模器
        this.createNewDiagram(reader.result)
      }
      return false
    },

    downloadBpmn() {
      this.bpmnModeler.saveXML({ format: true }, (err, xml) => {
        if (!err) {
          // 获取文件名
          const name = `${this.getFilename(xml)}.bpmn`
          // 将文件名以及数据交给下载方法
          this.download({ name: name, data: xml })
        }
      })
    },

    downloadSvg() {
      this.bpmnModeler.saveXML({ format: true }, (err, xml) => {
        if (!err) {
          // 获取文件名
          const name = `${this.getFilename(xml)}.svg`

          // 从建模器画布中提取svg图形标签
          let context = ''
          const djsGroupAll = this.$refs.canvas.querySelectorAll('.djs-group')
          for (let item of djsGroupAll) {
            context += item.innerHTML
          }
          // 获取svg的基本数据，长宽高
          const viewport = this.$refs.canvas.querySelector('.viewport').getBBox()

          // 将标签和数据拼接成一个完整正常的svg图形
          const svg = `
                      <svg
                        xmlns="http://www.w3.org/2000/svg"
                        xmlns:xlink="http://www.w3.org/1999/xlink"
                        width="${viewport.width}"
                        height="${viewport.height}"
                        viewBox="${viewport.x} ${viewport.y} ${viewport.width} ${viewport.height}"
                        version="1.1"
                        >
                        ${context}
                      </svg>
                    `
          // 将文件名以及数据交给下载方法
          this.download({ name: name, data: svg })
        }
      })
    },

    download({ name = 'diagram.bpmn', data }) {
      // 这里就获取到了之前设置的隐藏链接
      const downloadLink = this.$refs.downloadLink
      // 把输就转换为URI，下载要用到的
      const encodedData = encodeURIComponent(data)

      if (data) {
        // 将数据给到链接
        downloadLink.href = 'data:application/bpmn20-xml;charset=UTF-8,' + encodedData
        // 设置文件名
        downloadLink.download = name
        // 触发点击事件开始下载
        downloadLink.click()
      }
    },

    getFilename(xml) {
      let start = xml.indexOf('process')
      let filename = xml.substr(start, xml.indexOf('>'))
      filename = filename.substr(filename.indexOf('id') + 4)
      filename = filename.substr(0, filename.indexOf('"'))
      return filename
    },
  },
  computed: {},
}
</script>

<style lang="less" scoped>
// 左边工具栏以及编辑节点的样式
@import '~bpmn-js/dist/assets/diagram-js.css';
@import '~bpmn-js/dist/assets/bpmn-font/css/bpmn.css';
@import '~bpmn-js/dist/assets/bpmn-font/css/bpmn-codes.css';
@import '~bpmn-js/dist/assets/bpmn-font/css/bpmn-embedded.css';

// 右边工具栏样式
@import '~bpmn-js-properties-panel/dist/assets/bpmn-js-properties-panel.css';

.containers {
  position: absolute;
  background-color: #ffffff;
  width: 80%;
  height: 100vh;
  padding: 5px;
}

.canvas {
  width: 100%;
  height: 100%;
}

.panel {
  position: absolute;
  right: 0;
  top: 0;
  width: 300px;
}
</style>

结果如下：