camunda工作流引擎开发之旅01

背景：后端项目使用springboot+camunda来搭建，如果有微服务需求的，可以自己加上eureka和springcloud等大家庭。

目前maven所用到的依赖：

<properties>
		<java.version>1.8</java.version>
		<camunda.spring-boot.version>3.2.1</camunda.spring-boot.version>
		<spring-boot.version>2.1.1.RELEASE</spring-boot.version>
		<spring.cloud.version>Greenwich.RELEASE</spring.cloud.version>
		<maven.compiler.source>1.8</maven.compiler.source>
		<maven.compiler.target>1.8</maven.compiler.target>
		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
		<hk2.version>2.5.0</hk2.version>
		<mysql-connector.version>5.1.47</mysql-connector.version>
		<camunda-swagger.version>7.8.0</camunda-swagger.version>
		<camunda-spin.version>1.6.6</camunda-spin.version>
		<swagger-ui.version>3.20.9</swagger-ui.version>
		<springfox.version>2.9.2</springfox.version>
		<fastjson.version>1.2.31</fastjson.version>
	</properties>


	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter</artifactId>
		</dependency>

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
			<exclusions>
				<exclusion>
					<groupId>org.junit.vintage</groupId>
					<artifactId>junit-vintage-engine</artifactId>
				</exclusion>
			</exclusions>
		</dependency>
        <!--mybatis  依赖-->
		<dependency>
			<groupId>org.mybatis.spring.boot</groupId>
			<artifactId>mybatis-spring-boot-starter</artifactId>
			<version>1.1.1</version>
		</dependency>
		<dependency>
			<groupId>org.mybatis.generator</groupId>
			<artifactId>mybatis-generator-core</artifactId>
			<version>1.3.5</version>
		</dependency>

		<!-- https://mvnrepository.com/artifact/org.projectlombok/lombok -->
		<dependency>
			<groupId>org.projectlombok</groupId>
			<artifactId>lombok</artifactId>
			<version>1.18.2</version>
			<scope>provided</scope>
		</dependency>


		<dependency>
			<groupId>org.camunda.bpm.springboot</groupId>
			<artifactId>camunda-bpm-spring-boot-starter-rest</artifactId>
			<version>${camunda.spring-boot.version}</version>
		</dependency>
		<dependency>
			<groupId>org.camunda.bpm.springboot</groupId>
			<artifactId>camunda-bpm-spring-boot-starter-webapp</artifactId>
			<version>${camunda.spring-boot.version}</version>
		</dependency>
		<dependency>
			<groupId>org.camunda.spin</groupId>
			<artifactId>camunda-spin-dataformat-all</artifactId>
			<version>${camunda-spin.version}</version>
		</dependency>
		<dependency>
			<groupId>mysql</groupId>
			<artifactId>mysql-connector-java</artifactId>
			<version>${mysql-connector.version}</version>
		</dependency>

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-devtools</artifactId>
			<optional>true</optional>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-jdbc</artifactId>
		</dependency>
		<dependency>
			<groupId>org.glassfish.hk2</groupId>
			<artifactId>hk2</artifactId>
			<version>${hk2.version}</version>
		</dependency>
		<dependency>
			<groupId>org.glassfish.hk2</groupId>
			<artifactId>spring-bridge</artifactId>
			<version>${hk2.version}</version>
		</dependency>
		<dependency>
			<groupId>org.camunda.bpm.extension.swagger</groupId>
			<artifactId>camunda-bpm-swagger-json</artifactId>
			<version>${camunda-swagger.version}</version>
		</dependency>
		<dependency>
			<groupId>org.webjars</groupId>
			<artifactId>swagger-ui</artifactId>
			<version>${swagger-ui.version}</version>
		</dependency>

		<dependency>
			<groupId>io.springfox</groupId>
			<artifactId>springfox-swagger2</artifactId>
			<version>${springfox.version}</version>
		</dependency>
		<dependency>
			<groupId>io.springfox</groupId>
			<artifactId>springfox-swagger-ui</artifactId>
			<version>${springfox.version}</version>
		</dependency>

		<dependency>
			<groupId>org.apache.commons</groupId>
			<artifactId>commons-lang3</artifactId>
		</dependency>
		<dependency>
			<groupId>com.alibaba</groupId>
			<artifactId>fastjson</artifactId>
			<version>${fastjson.version}</version>
		</dependency>
		<dependency>
			<groupId>de.odysseus.juel</groupId>
			<artifactId>juel-impl</artifactId>
			<version>2.2.7</version>
		</dependency>
	</dependencies>

主要有springboot家庭的，还有mybatis与mysql的，项目的背景主要就是建立一个后端的camunda引擎项目，用于学习以及给前端做工作流业务使用。

camunda脱胎于activiti，我本来是看了一点activiti的api，后面转camunda的时候，毫无阻塞，而camunda的社区也更友好点，更新也强点，就选定了camunda。

camunda主要学习方式通过它的官方api，只是api纯英文，大佬们可以自行翻看
camunda支持自动扫描resources下的bpmn文件，在项目启动时自动部署到环境中，如果有改动的bpmn，则算是版本更新，我项目主要是从前端进行部署bpmn，所以此功能被我在配置文件中关闭了。
具体可在processes.xml的false以及application.yaml中camunda.bpm.auto-deployment-enabled: false来设置，测试过发现只要在yml中设置了即不会自动部署了。
yml配置：

server:
  port: 8080
  tomcat:
    uri-encoding: UTF-8
  servlet:
    context-path: /camundaDemo

spring:
  application:
    name: camunda-demo-service
  jersey:
    application-path: /engine-rest
  datasource:
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://127.0.0.1:3306/camunda_demo2?useUnicode=true&characterEncoding=UTF-8&autoReconnect=true&useSSL=false&useOldAliasMetadataBehavior=true
    username: root
    password:  ***
    tomcat:
      max-idle: 10
      max-wait: 10000
      min-idle: 5
      initial-size: 5
      validation-query: SELECT 1
      test-on-borrow: false
      test-while-idle: true
      time-between-eviction-runs-millis: 18800

camunda.bpm:
  filter:
    create: All tasks
  database:
    type: mysql
  admin-user:
    id: cheey
    password: superSecret
    firstName: cheey
  auto-deployment-enabled: false
  webapp:
    index-redirect-enabled: false
mybatis:
  typeAliasesPackage: com.fs.camunda.bpm.example.entity
  mapper-locations: classpath:mybatis/mapper/*.xml

application-path: /engine-rest是web端访问rest api必须加上的路径，
admin-user这类的是基于jar中加载了自己的camunda web端配置的账号密码，程序运行时会自动在数据库创建，web端也可以关闭
webapp:
index-redirect-enabled: false 这就是关闭web端

这篇就先说配置文件了